leed ncv2.1 ss

LEED-NC Version 2.1 Reference Guide

7

IDEASS WE MR EQ

Development and construction processesare often destructive to local ecology.These activities also encroach on produc-tive agricultural land areas and open space.Stormwater runoff from developed areascan impact water quality in receiving wa-ters, hinder navigation and recreation, anddisrupt aquatic life. Fortunately, steps canbe taken to reduce impacts on previouslyundeveloped lands and to improve previ-ously contaminated sites.

Selection of an appropriate project loca-tion can reduce the need for private au-tomobile use and reduce urban sprawl.Locating developments on existingbrownfield sites, in existing urban infillareas and on other non-greenfield loca-tions may have economic benefits. Forexample, the infrastructure to service thedevelopment may already be in place.

Sustainable Sites Overview

Overview of LEEDTM

Prerequisites andCredits

SS Prerequisite 1Erosion &Sedimentation Control

SS Credit 1Site Selection

SS Credit 2Urban Redevelopment

SS Credit 3BrownfieldRedevelopment

SS Credit 4AlternativeTransportation

SS Credit 5Reduced SiteDisturbance

SS Credit 6StormwaterManagement

SS Credit 7Landscape & ExteriorDesign to ReduceHeat Islands

SS Credit 8Light PollutionReduction

There are 14 pointsavailable in theSustainable Sitescategory.

When considering site alternatives, it isimportant to consider environmental cri-teria throughout the site selection process.

The major ecological features of the siteshould be identified, including the site ge-ology, hydrology, vegetation, wildlife andprior site history. Communication withproject stakeholders, including buildingoccupants, the general public and siteneighbors can be facilitated through pub-lic meetings, design charrettes and orga-nized comment processes.

It is also important to minimize projectimpacts on surrounding areas after con-struction is complete and the building isoccupied. By addressing heat island ef-fects and reducing light pollution on thesite, the site can become integrated intoits surroundings and serve as a consider-ate and beneficial neighbor for the life-time of the building.

U.S. Green Building Council

8

IDEASS WE MR EQ

Overview


9

IDEASS WE MR EQ

Erosion & Sedimentation Control

Intent

Control erosion to reduce negative impacts on water and air quality.

Requirements

Design a sediment and erosion control plan, specific to the site, that conforms toUnited States Environmental Protection Agency (EPA) Document No. EPA 832/R-92-005 (September 1992), Storm Water Management for Construction Activities,Chapter 3, OR local erosion and sedimentation control standards and codes, which-ever is more stringent. The plan shall meet the following objectives:

● Prevent loss of soil during construction by stormwater runoff and/or winderosion, including protecting topsoil by stockpiling for reuse.

● Prevent sedimentation of storm sewer or receiving streams.

● Prevent polluting the air with dust and particulate matter.

Submittals

❏ Provide the LEED Letter Template, signed by the civil engineer or responsible party,declaring whether the project follows local erosion and sedimentation control stan-dards or the referenced EPA standard. Provide a brief list of the measures imple-mented. If local standards and codes are followed, describe how they meet or exceedthe referenced EPA standard.

Summary of Referenced Standard

Storm Water Management for Construction Activities (USEPA Document No. EPA832R92005), Chapter 3

U.S. Environmental Protection Agency Office of Water, www.epa.gov/OW

Internet download link for Chapter 3 (72 pages): www.epa.gov/npdes/pubs/chap03_conguide.pdf. Download site for all sections: http://yosemite.epa.gov/water/owrccatalog.nsf, search by title index.

Hardcopy or microfiche (entire document, 292 pages): National Technical Informa-tion Service (order # PB92-235951), www.ntis.gov, (800) 553-6847

This standard describes two types of measures that can be used to control sedimenta-tion and erosion. Stabilization measures include temporary seeding, permanent seed-ing and mulching. All of these measures are intended to stabilize the soil to preventerosion. Structural control measures are implemented to retain sediment after erosionhas occurred. Structural control measures include earth dikes, silt fencing, sedimenttraps and sediment basins. The application of these measures depends on the condi-tions at the specific site. If local provisions are substantially similar, they can be substi-tuted for this standard if it is demonstrated that local provisions meet or exceed theEPA best management practices.

Prerequisite 1

Required


10

IDEASS WE MR EQ Green Building ConcernsSite clearing and earth moving duringconstruction often results in significanterosion problems because adequate envi-ronmental protection strategies are notemployed. Erosion results from precipi-tation and wind processes, leading to deg-radation of property and sedimentationof local water bodies. This affects waterquality as well as navigation, fishing andrecreation activities. Fortunately, mea-sures can be implemented to minimize siteerosion during construction and to avoiderosion once the buildings are occupied.

Environmental Issues

Contaminated water that flows into re-ceiving waters disrupts stream and estu-ary habitats. Contributors to erosionproblems include destruction of vegeta-tion that previously slowed runoff andreconfiguration of natural site grading.Controlling stormwater runoff reduceserosion and contamination of receivingwaters.

Economic Issues

Erosion and sedimentation control doesnot necessarily add cost to a project. Re-duction of sedimentation and erosionthrough landscaping and other measurescan in fact reduce the size, complexity andcost of stormwater management mea-sures. While there are additional costsassociated with identifying soil conditionsat the site, the knowledge gained can helpavoid problems over the building lifetime.For instance, soil erosion issues associatedwith unstable foundations and potentialloss of structural integrity can be avoidedif soil conditions are documented in ad-vance and used in the building design.

Landscaping activities to prevent soil ero-sion include augmentation of poor soiland inclusion of specialized plantings inthe landscape design to retain soil in place.Excessive landscaping may require main-tenance over time, resulting in additional

operation costs. Use of native plants re-duces both watering and maintenancerequirements.

Community Issues

Communities benefit from reduced ero-sion and sedimentation control throughimproved water quality in local streams,rivers and lakes. These water bodies arevaluable to communities for sustenance,navigation and recreation.

Design Approach

Strategies

As a general approach to achieve thiscredit: (1) identify the soil compositionon the project site, (2) uncover potentialsite problems, and (3) develop mitigationstrategies. Protect erosion-prone areasfrom construction activities, and imple-ment a soil stabilization plan in suscep-tible areas. The plan should include strin-gent erosion control requirements in con-struction drawings and specifications tocontrol erosion and sedimentation dur-ing construction activities. In additionto construction controls, design theproject site to minimize erosion and sedi-mentation processes over the lifetime ofthe building.

Erosion and sedimentation control mea-sures should be addressed in an ErosionControl Plan. This plan often coversstormwater management in addition toerosion control because these concepts areintimately linked. The document shouldinclude the following information:

1. Statement of erosion control andstormwater control objectives

2. Comparison of post-developmentstormwater runoff conditions withpredevelopment conditions

3. Description of all temporary and per-manent erosion control and stormwatercontrol measures implemented on theproject site

Prerequisite 1

Credit Synergies








WE Credit 1Water EfficientLandscaping


11

IDEASS WE MR EQ4. Description of the type and frequencyof maintenance activities required for thechosen erosion control methods

Consider augmenting the project designteam with an expert in sustainable land-scape architecture and land planning. Theexpert should be familiar with local andstate legal requirements for erosion con-trol, as well as strategies and technologiesto minimize erosion and sedimentation.

Technologies

Table 1 describes technologies for con-trolling erosion and sedimentation as rec-ommended by the referenced standard.

Synergies and Trade-Offs

Measures for erosion and sedimentationcontrol are dependent on site location andsite design. These measures are often in-tegrated with stormwater managementplans because stormwater is a large con-tributor to erosion problems. Landscap-

ing strategies have a significant effect onerosion. The most suitable areas on a sitefor a building in terms of passive solargains or environmental quality benefitsmay be inappropriate due to problematicsoil conditions. Conversely, landscapingthat is planted for soil erosion mitigationmight affect passive solar gains or windcurrents used for natural ventilation.

Definitions

Erosion is a combination of processes inwhich materials of the earth’s surface areloosened, dissolved or worn away, andtransported from one place to another bynatural agents.

Sedimentation is the addition of soils towater bodies by natural and human-re-lated activities. Sedimentation decreaseswater quality and accelerates the agingprocess of lakes, rivers and streams.

Prerequisite 1

Table 1: Technologies for Controlling Erosion & Sedimentation

Control Technology Description

Stabilization

Temporary SeedingPlant fast-growing grasses to temporarily stabilize soils.

Permanent SeedingPlant grass, trees, and shrubs to permanently stabilize soil.

MulchingPlace hay, grass, woodchips, straw, or gravel on the soil surface to cover and hold soils.

Structural Control

Earth DikeConstruct a mound of stabilized soil to divert surface runoff volumes from disturbed areas or into sediment basins or sediment traps.

Silt FenceConstruct posts with a filter fabric media to remove sediment from stormwater volumes flowing through the fence.

Sediment TrapExcavate a pond area or construct earthen embankments to allow for settling of sediment from stormwater volumes.

Sediment BasinConstruct a pond with a controlled water release structure to allow for settling of sediment from stormwater volumes.


12

IDEASS WE MR EQ

Prerequisite 1

Case Study

Donald Bren School of Environmental Scienceand ManagementSanta Barbara, California

The University of California at Santa Barbara’s Donald BrenSchool of Environmental Science and Management is a LEED™Version 1.0 Platinum Pilot Project. The Bren School houses cam-pus facilities including research and teaching laboratories, andoffices. An erosion control plan was instituted for the project toprevent contaminated runoff from leaving the site boundary.Construction stormwater controls included temporary silt fenc-ing and straw-bale catch basins. Project specifications and plansincluded requirements to preserve topsoil and limit site distur-bance. During construction, grading activities were scheduled inaccordance with weather conditions. Construction materialsstored on-site were protected from the elements to prevent con-tamination of stormwater volumes, and construction workers wereinformed of the stormwater control program. During buildingoccupancy, stormwater system inspections are scheduled to oc-cur annually, before and after storm events, and weekly to ensureproper operation of stormwater controls.

OwnerUniversity of California at Santa Barbara

Courtesy of Zimmer Gunsul Frasca Partnership


13

IDEASS WE MR EQ

Site Selection

Intent

Avoid development of inappropriate sites and reduce the environmental impact fromthe location of a building on a site.

Requirements

Do not develop buildings, roads or parking areas on portions of sites that meet any oneof the following criteria:

● Prime farmland as defined by the United States Department of Agriculture inthe United States Code of Federal Regulations, Title 7, Volume 6, Parts 400 to699, Section 657.5 (citation 7CFR657.5).

● Land whose elevation is lower than 5 feet above the elevation of the 100-yearflood as defined by the Federal Emergency Management Agency (FEMA).

● Land which is specifically identified as habitat for any species on Federal orState threatened or endangered lists.

● Within 100 feet of any water including wetlands as defined by United StatesCode of Federal Regulations 40 CFR, Parts 230-233 and Part 22, and isolatedwetlands or areas of special concern identified by state or local rule, OR greaterthan distances given in state or local regulations as defined by local or staterule or law, whichever is more stringent.

● Land which prior to acquisition for the project was public parkland, unlessland of equal or greater value as parkland is accepted in trade by the publiclandowner (Park Authority projects are exempt).

Submittals

❏ Provide the LEED Letter Template, signed by the civil engineer or responsibleparty, declaring that the project site meets the credit requirements.

Summary of Referenced Standards

U.S. Department of Agriculture Definition of Prime Agricultural Land as stated inUnited States Code of Federal Regulations Title 7, Volume 6, Parts 400 to 699, Sec-tion 657.5 (citation 7CFR657.5) www.access.gpo.gov/nara/ (go to “browse your choiceof CFR titles and/or volumes”)

This standard states: “Prime farmland is land that has the best combination ofphysical and chemical characteristics for producing food, feed, forage, fiber, andoilseed crops, and is also available for these uses (the land could be cropland,pastureland, rangeland, forest land, or other land, but not urban built-up land orwater). It has the soil quality, growing season, and moisture supply needed toeconomically produce sustained high yields of crops when treated and managed,including water management, according to acceptable farming methods. In general,prime farmlands have an adequate and dependable water supply from precipitation

Credit 1

1 point


14

IDEASS WE MR EQ

Credit 1

or irrigation, a favorable temperature and growing season, acceptable acidity oralkalinity, acceptable salt and sodium content, and few or no rocks. They are perme-able to water and air. Prime farmlands are not excessively erodible or saturated withwater for a long period of time, and they either do not flood frequently or areprotected from flooding. Examples of soils that qualify as prime farmland arePalouse silt loam, 0 to 7 percent slopes; Brookston silty clay loam, drained; andTama silty clay loam, 0 to 5 percent slopes.”

Federal Emergency Management Agency (FEMA) 100-Year Flood Definition

Federal Emergency Management Agency, www.fema.gov, (202) 646-4600

This referenced standard addresses flood elevations. FEMA defines a 100-Year Floodas the flood elevation that has a 1% chance of being reached or exceeded each year. Itis not the most significant flood in a 100-year period. Instead, 100-year floods canoccur many times within a 100-year period. See the FEMA Web site for comprehen-sive information on floods and other natural disasters such as wildfires and hurricanes.

Endangered Species Lists

U.S. Fish and Wildlife Service’s List of Threatened and Endangered Species,endangered.fws.gov

This referenced standard addresses threatened and endangered wildlife and plants. TheService also maintains a list of plants and animals native to the United States that arecandidates for possible addition to the federal list.

National Marine Fisheries Service’s List of Endangered Marine Species,www.nmfs.noaa.gov/endangered.htm

Consult state agencies for state-specific lists of endangered or threatened wildlife andplant species.

Definition of Wetlands in the United States Code of Federal Regulations, 40 CFR,Parts 230-233, and Part 22

www.access.gpo.gov/nara/cfr/index.html, (888) 293-6498

This referenced standard addresses wetlands and discharges of dredged or filled mate-rial into waters regulated by states. The definition of wetland areas pertaining to thiscredit, found in Part 230, is as follows:

“Wetlands consist of areas that are inundated or saturated by surface or ground waterat a frequency and duration sufficient to support, and that under normal circum-stances do support, a prevalence of vegetation typically adapted for life in saturated soilconditions.”


15

IDEASS WE MR EQAppropriate site selection can reduce therisk of property damage due to naturalevents such as landslides, floods, sinkholesand soil erosion. Higher first costs maybe encountered due to site survey and se-lection activities. Increased property val-ues can offset these costs in the future.

Proper site selection can also avoid po-tential loss of property due to potentiallitigation resulting from harm to endan-gered species.

Community Issues

Prudent site selection can enhance prop-erty values within the community whendevelopment is integrated into the sur-rounding ecosystem. For example, byclustering buildings in a neighborhood,green space can be set aside for parks andcommunity gathering spaces. Thought-ful site selection and planning can alsoallow the developer to integrate uniqueneighborhood characteristics duringproject design.

Design Approach

Strategies

Avoid developing sites that exhibit anyof the characteristics listed in the re-stricted criteria. Consider the proposeduse of the building, and set a preferencefor previously developed sites thatcomplement the use, thereby reducingassociated parking needs and vehicularmiles traveled. The site selection processmight include landscape architects, ecolo-gists, environmental engineers and civilengineers, as well as local professionalswho can provide site-specific expertise.

Have a government official, ecologist orother qualified professional perform a sitesurvey to inventory the important environ-mental characteristics, including wetlands,sloped areas, unique habitat areas and for-ested areas. Zoning requirements of thelocal municipality and the communitymaster plan should be integrated to the

Green Building ConcernsAs non-urban development increases, theimportance of prudent site selection in-creases as well. Prevention of habitat en-croachment is an essential element of sus-tainable site selection. The best strategyfor selecting a building site is to choose apreviously developed site. Since these siteshave already been disturbed, damage tothe environment is limited and sensitiveland areas can be preserved.

The site surrounding a building definesthe character of the building and providesthe first impression for occupants and visi-tors to the building. Creative and carefulsite designs can integrate the natural sur-roundings with the building(s), provid-ing a strong connection between the builtand natural environments and minimiz-ing adverse impacts on the non-built por-tions of the site.


Habitat preservation is the most effectivemeans to meet the requirements of theEndangered Species Act and to minimizedevelopmental impacts on indigenouswildlife. Not building on inappropriatesites preserves these areas for wildlife, rec-reation and ecological balance. Buildingon inappropriate sites such as floodplainscan be detrimental to ecosystems.

Economic Issues

Site selection can play an important rolein the way in which the public respondsto, and is involved with, the proposeddevelopment. Channeling developmentaway from sensitive ecological areas infavor of previously disturbed sites canencourage public support for a project andspeed public review periods, thus mini-mizing or preventing obstacles tradition-ally encountered during project scoping.Economically, this can also save on miti-gation costs that a developer would incurif the proposed development were ap-proved within a sensitive area.

Credit 1

Credit Synergies

SS Prerequisite 1Erosion & SedimentationControl








MR Credit 1Building Reuse

EQ Credit 8Daylight & Views


16

IDEASS WE MR EQ greatest extent possible. Community co-ordination and consideration of publiccomments can help pre-empt negative com-munity reaction. Where feasible, integrateneighboring activities to create a develop-ment with shared amenities and spaces.

When designing the building, consider asmaller footprint, and set aside large con-tiguous areas for natural space on the projectsite. Build in dense blocks to limit the de-velopment footprint and site disturbanceto the smallest area possible. Incorporatesite features into the design such as naturalfeatures that already exist on the site, natu-ral shelter from trees or terrain, natural ar-eas for outdoor activities, and water featuresfor thermal, acoustic and aesthetic benefit.


Site selection is the basis of site design andaffects all aspects of the site, includingtransportation amenities, natural areas,stormwater management, amount of im-pervious surfaces, and site lighting require-ments. Water supply and managementissues, especially landscape irrigation andstormwater reuse, are dependent on projectlocation. Opportunities to increase thebuilding’s energy performance can be re-alized by locating the project in areas wherenatural ventilation and solar gains can bemanaged and based on the angles and lo-cation of the sun. The local climate andmarketplace should influence choices ofmaterials. Natural ventilation and daylightcan benefit indoor environmental quality.

Resources

Web Sites

ESRI

www.esri.com/hazards/makemap.html

This software company creates tools forGIS mapping. Its Web site includes anoption to make a map of all of the floodareas within a user-defined location.

Natural Resources Defense Council

www.nrdc.org, (212) 727-2700

NRDC uses law, science, and a largemembership base for protection of wild-life and wild places to ensure a safe andhealthy environment.

Print Media

Constructed Wetlands in the SustainableLandscape by Craig Campbell andMichael Ogden, John Wiley & Sons,1999.

Holding Our Ground: ProtectingAmerica’s Farms and Farmland by TomDaniels and Deborah Bowers, IslandPress, 1997.

Saved By Development: Preserving En-vironmental Areas, Farmland by RickPruetz, Arje Press, 1997.

Wetland Indicators: A Guide to WetlandIdentification, Delineation, Classifica-tion, and Mapping by Ralph W. Tiner,Lewis Publishers, 1999.

Definitions

A Community is an interacting popula-tion of individuals living in a specific area.

The Development Footprint is the areaon the project site that has been impactedby any development activity. Hardscape,access roads, parking lots, non-buildingfacilities and building structure are all in-cluded in the development footprint.

An Ecosystem is a basic unit of naturethat includes a community of organismsand their nonliving environment linkedby biological, chemical, and physical pro-cess.

An Endangered Species is an animal orplant species that is in danger of becom-ing extinct throughout all or a significantportion of its range due to harmful hu-man activities or environmental factors.

A Threatened Species is an animal orplant species that is likely to become en-dangered within the foreseeable future.

Credit 1


17

IDEASS WE MR EQWetland Vegetation consists of plants thatrequire saturated soils to survive as wellas certain tree and other plant species thatcan tolerate prolonged wet soil conditions.

Credit 1


18

IDEASS WE MR EQ

Credit 1


19

IDEASS WE MR EQ

Development Density

Intent

Channel development to urban areas with existing infrastructure, protect greenfieldsand preserve habitat and natural resources.

Requirements

Increase localized density to conform to existing or desired density goals by utilizingsites that are located within an existing minimum development density of 60,000 squarefeet per acre (two story downtown development).

Submittals

❏ Provide the LEED Letter Template, signed by the civil engineer, architect or otherresponsible party, declaring that the project has achieved the required develop-ment densities. Provide density for the project and for the surrounding area.

❏ Provide an area plan with the project location highlighted.


There is no standard referenced for this credit.

Credit 2

1 point


20

IDEASS WE MR EQ

Credit 2Green Building ConcernsThe development of open space awayfrom urban cores and other existing de-velopment may reduce a property’s firstcost, but this development paradigm hasfar-reaching negative consequences for theenvironment and the community. Build-ing occupants become increasingly depen-dent on private automobiles for commut-ing. As travel distances increase, this re-sults in more air and water pollution.Prime agricultural land is lost and previ-ously developed urban sites fall into dis-use and decay. Utility, transportation andcommunity support infrastructure mustalso be developed to support the peoplewho utilize new buildings. These infra-structure requirements increase thedevelopment’s impact far beyond the ini-tial project scope. In contrast, urban re-development is an effective strategy tocurb suburban sprawl, tap into existinginfrastructure and conserve rapidly dis-appearing greenfield space.


By maintaining density in cities, agricul-tural land and greenfield areas are pre-served for future generations. Mass trans-portation in urban areas can be an attrac-tive alternative mode of transportation,reducing impacts associated with auto-mobile use. Building in urban areas re-duces the number of vehicle miles trav-eled and, thus, reduces pollution causedby automobiles. The use of existing util-ity lines, roadways, parking, landscapingcomponents and other services eliminatesthe environmental impacts of construct-ing these features for non-urban devel-opments.

Economic Issues

A significant economic benefit of infill de-velopment is the reduction or eliminationof new infrastructure, including roads, util-ity services and other amenities already inplace. If mass transit serves the urban site,significant cost reductions are possible by

downsizing the project parking capacity.Urban infill development sometimes re-quires significant additional costs whencompared with suburban developmentdue to site constraints, contaminated soilsand other issues. Municipal and countyincentives for urban infill projects may alsobe available.

Community Issues

Urban sprawl affects quality of life be-cause commuters must spend increasingamounts of time in their automobiles. Inaddition, families often need more ve-hicles to accommodate family needs, re-sulting in a higher cost of living and lessfree time. The redevelopment of urbanareas helps restore, invigorate and sustainestablished urban living patterns, creat-ing a more stable and interactive com-munity.

Design Approach

Strategies

The general approach for achieving thiscredit is to give preference to sites withinan existing urban fabric. Work with lo-cal jurisdictions and follow the urban de-velopment plan to meet or exceed den-sity goals. Consider synergies with neigh-bors and choose sites based on infrastruc-ture, transportation and quality-of-lifeconsiderations. Sites with redevelopmentplans that will achieve the required de-velopment density by the completion ofthe project should not be excluded fromconsideration. This credit can beachieved by choosing to develop a sitewhere a community revitalization is oc-curring provided the required develop-ment density is achieved by the project’scompletion.


Urban redevelopment affects all areas ofsite design including site selection, espe-cially transportation planning, the over-all building footprint and stormwater

Credit Synergies








MR Prerequisite 1Storage & Collection ofRecyclables


MR Credit 2Construction WasteManagement

MR Credit 3Resource Reuse

EQ Prerequisite 1Minimum IAQPerformance

EQ Credit 2Increase VentilationEffectiveness



21

IDEASS WE MR EQmanagement. Urban sites often involvethe rehabilitation of an existing building,with a reduction of construction wasteand new material use. However, thesesites may also have limited space avail-able for construction waste managementactivities and occupant recycling pro-grams. Urban sites may have negativeIEQ aspects such as contaminated soils,undesirable air quality or limiteddaylighting applications.

Calculations

The following calculation methodologyis used to support the credit submittalslisted on the first page of this credit. Todetermine the development density of aproject, both the project density and thedensities of surrounding developmentsmust be calculated. The extent of neigh-boring areas to include in density calcu-lations varies depending upon the size ofthe project. Larger projects are requiredto consider a greater number of neigh-boring properties than smaller projects.The density calculation process is de-scribed in the following steps:

1. Determine the total area of the projectsite and the total square footage of thebuilding. For projects that are part of alarger property (such as a campus), de-fine the project area as that which is de-fined in the project’s scope. The projectarea must be defined consistentlythroughout LEED documentation.

2. Calculate the development density forthe project by dividing the total squarefootage of the building by the total sitearea in acres. This development density

must be equal to or greater than 60,000square feet per acre (see Equation 1).

3. Convert the total site area from acresto square feet and calculate the squareroot of this number. Then multiply thesquare root by three to determine the ap-propriate density radius. (Note: thesquare root function is used to normalizethe calculation by removing effects of siteshape.) (see Equation 2).

4. Overlay the density radius on a mapthat includes the project site and sur-rounding areas, originating from the cen-ter of the site. This is the density bound-ary. Include a scale on the map.

5. For each property within the densityboundary and for those properties thatintersect the density boundary, create atable with the building square footage andsite area of each property. Include allproperties in the density calculations ex-cept for undeveloped public areas suchas parks and water bodies. Do not in-clude public roads and right-of-way ar-eas. Information on neighboring prop-erties can be obtained from your city orcounty zoning department.

6. Add all the square footage values andsite areas. Divide the total square foot-age by the total site area to obtain theaverage property density within the den-sity boundary. The average property den-sity of the properties within the densityboundary must be equal to or greater than60,000 square feet per acre.

The following example illustrates theproperty density calculations: A 30,000-square-foot building is located on a 0.44-

Equation 1:

Equation 2:

××=acre

SF43,560]acres[ArearopertyP3]LF[

DensityRadius

Credit 2

]acres[AreaProperty

]SF[FootageSquareBuilding

acre

SFDevelopmentDensity

=


22

IDEASS WE MR EQ

Credit 2

Figure 1: An Illustration of a Sample Area Plan

scale:

415’

0’ 200’north

T R

S

Q P

O

N

M

LK

J

I

H G

EF

DC

B

A

V U

XW

acre urban site and the calculations areused to determine the building density.The building density is above the mini-mum density of 60,000 square feet peracre required by the credit (see Table 1).

Next, the density radius is calculated. Adensity radius of 415 feet is calculated (seeTable 2).

The density radius is applied to an areaplan of the project site and surroundingarea. The plan identifies all properties thatare within or are intersected by the den-sity radius. The plan includes a scale anda north indicator.

Table 3 below summarizes the informa-tion about the properties identified on themap. The building space and site areaare listed for each property. These values

are summed and the average density iscalculated by dividing the total buildingspace by the total site area.

For this example, the average buildingdensity of the surrounding area is greaterthan 60,000 square feet per acre, and,thus, the example qualifies for one pointunder this credit.

Resources

Web Sites

International Union for the ScientificStudy of Population

www.iussp.org

IUSSP promotes scientific studies of de-mography and population-related issues.


23

IDEASS WE MR EQ

Credit 2

Table 2: Density Radius Calculation

Table 3: Sample Area Properties

Site Area [acres] 0.44

Density Radius [LF] 415

Density Radius Calculation

Buildings within Density Radius

Building Space

SiteArea

Buildings within Density Radius

Building Space

SiteArea

[SF] [acres] [SF] [acres]

A 33,425 0.39 N 28,740 0.30

B 87,500 1.58 O 6,690 0.15

C 6,350 0.26 P 39,000 0.39

D 27,560 0.32 Q 348,820 2.54

E 66,440 1.17 R 91,250 1.85

F 14,420 1.36 S 22,425 0.27

G 12,560 0.20 T 33,650 0.51

H 6,240 0.14 U 42,400 0.52

I 14,330 0.22 V - 0.76

J 29,570 0.41 W 19,200 0.64

K 17,890 0.31 X 6,125 0.26

L 9,700 0.31 Y 5,000 0.30

M 24,080 0.64 Z 4,300 0.24

Total Building Space [SF] 997,665

Total Site Area [acres] 16.04

AVERAGE DENSITY [SF/acres] 62,199

Urban Land Institute

www.uli.org, (800) 321-5011

The Urban Land Institute is a nonprofiteducation and research institute that is sup-ported by its members. Its mission is to pro-vide responsible leadership in the use of landin order to enhance the total environment.

Print Media

Changing Places: Rebuilding Commu-nity in the Age of Sprawl by RichardMoe and Carter Wilkie, Henry Holt &Company, 1999.

Density by Design: New Directions inResidential Development, Steven Fader,Urban Land Institute, 2000.

Green Development: Integrating Ecol-ogy and Real Estate, by Alex Wilson etal., John Wiley & Sons, 1998.

Once There Were Greenfields: How Ur-ban Sprawl Is Undermining America’sEnvironment, Economy, and SocialFabric by F. Kaid Benfield et al., NaturalResources Defense Council, 1999.

Suburban Nation: The Rise of Sprawland the Decline of the AmericanDream by Andres Duany et al., NorthPoint Press, 2000.

Table 1: Property Density Calculations

ProjectBuildings

BuildingSpace

[SF]

SiteArea[acres]

Project 30,000 0.44

Density [SF/acre] 68,182


24

IDEASS WE MR EQ

Credit 2

Case Study

KSBA Architects Office BuildingPittsburgh, Pennsylvania

The KSBA Architects office building is a LEED™ Certified Pi-lot Project located in the Lawrenceville section of Pittsburgh. Thebuilding is a rehabilitation project of a building originally con-structed in 1888 and is part of a decade-long neighborhood revi-talization program involving several local jurisdictions and com-munity planning agencies. The two-story building is located in aneighborhood that includes a variety of businesses and indus-tries, all within close proximity to downtown Pittsburgh. Thelocation benefits the building occupants by providing a neigh-borhood that is conducive to walking, eating, entertainment,transportation and living.

OwnerKSBA Architects

Courtesy of KSBA Architects

Definitions

A Greenfield is undeveloped land or landthat has not been impacted by humanactivity.

Property Area is the legal propertyboundary of a project and includes allareas of the site including constructed ar-eas and non-constructed areas.

Site Area is defined the same as propertyarea.

The Square Footage of a building is thetotal area in square feet of all rooms in-cluding corridors, elevators, stairwells andshaft spaces.


25

IDEASS WE MR EQ

Brownfield Redevelopment

Intent

Rehabilitate damaged sites where development is complicated by real or perceived en-vironmental contamination, reducing pressure on undeveloped land.

Requirements

Develop on a site documented as contaminated (by means of an ASTM E1903-97Phase II Environmental Site Assessment) OR on a site classified as a brownfield by alocal, state or federal government agency. Effectively remediate site contamination.

Submittals

❏ Provide a copy of the pertinent sections of the ASTM E1903-97 Phase II Environ-mental Site Assessment documenting the site contamination OR provide a letterfrom a local, state or federal regulatory agency confirming that the site is classifiedas a brownfield by that agency.

❏ Provide the LEED Letter Template, signed by the civil engineer or responsibleparty, declaring the type of damage that existed on the site and describing theremediation performed.


ASTM E1903-97 Phase II Environmental Site Assessment

ASTM International, www.astm.org

This guide covers a framework for employing good commercial and customary prac-tices in conducting a Phase II environmental site assessment of a parcel of commercialproperty. It covers the potential presence of a range of contaminants that are within thescope of CERCLA, as well as petroleum products.

EPA Brownfields Definition

EPA Sustainable Redevelopment of Brownfields Program, www.epa.gov/brownfields

With certain legal exclusions and additions, the term “brownfield site” means realproperty, the expansion, redevelopment, or reuse of which may be complicated by thepresence or potential presence of a hazardous substance, pollutant or contaminant(source: Public Law 107-118, H.R. 2869 – “Small Business Liability Relief andBrownfields Revitalization Act”). See the Web site for additional information andresources.

Credit 3

1 point


26

IDEASS WE MR EQ

Credit Synergies









MR Credit 3Resource Reuse


Green Building ConcernsMany potential building sites in urbanlocations have been abandoned due to realor perceived contamination from previ-ous industrial or municipal activities.These sites can be remediated and rede-veloped for reuse. Environmental andeconomic concerns are key issues whenevaluating brownfield redevelopment.Costs incurred to remediate site contami-nation and land prices can be additive orcan offset each other. Perception of thebuilding site by the building owner andfuture building occupants must also beweighed. Building owners may be waryof cleanup requirements and the poten-tial for liability associated with contami-nants migrating off-site and impactingdownstream neighbors. Building occu-pants may worry about health risks frombreathing contaminated air or cominginto contact with contaminated soil.These concerns must be investigated andresolved before making the final decisionto redevelop a brownfield site.


Remediation efforts remove hazardousmaterials from brownfield sites’ soil andgroundwater. This reduces the exposureof humans and wildlife to health risks asa result of environmental pollution. Re-development of brownfield sites providesan alternate option to developing ongreenfield sites. Preservation of greenfieldsites for future generations decreases theoverall environmental impact of develop-ment. Brownfields often have existinginfrastructure improvements in place in-cluding utilities and roads, reducing theneed for further environmental impactsdue to construction of new infrastructure.In some instances, rather than remediatethe contamination, it may be more sen-sible to leave contaminants in place,choosing instead to stabilize and isolatethe contaminants from human exposure.

Economic Issues

Brownfields can offer an attractive loca-tion and are often inexpensive when com-pared to comparable uncontaminatedproperties. It is essential to weigh thevalue of the remediated property againstcleanup costs to determine if the site iseconomically viable for redevelopment.Developers have been reluctant to rede-velop brownfield sites in the past due topotential liability associated with takingresponsibility for the cleanup of others’contamination. In recent years, the EPAand many state and local governmentagencies have begun to provide incentivesfor brownfield redevelopment by enact-ing laws that reduce the liability of devel-opers who choose to remediate contami-nated sites. Before embarking on abrownfield development effort, it is im-portant to contact state and local regula-tors to determine the rules governing thesesites and available financial assistance pro-grams. It may also be helpful to contactthe regional EPA’s Office of Solid Wasteand Emergency Response (OSWER),which may provide site characterizationand remediation support.

Community Issues

Reclaiming contaminated sites can con-tribute to social and economic revitaliza-tion within neighborhoods by taking alocal liability and turning it into an asset.Cleaning up contaminated properties caninstill a new sense of pride in local resi-dents, and it can also provide the incen-tive to improve nearby properties.

Design Approach

Strategies

Gain community support by highlight-ing the environmental, economic andcommunity-related benefits of brownfieldredevelopment. Negotiate with localmunicipalities and landowners for below-

Credit 3


27

IDEASS WE MR EQmarket purchase prices for brownfield realestate. Also, obtain tax incentives bymeeting the locally applicable require-ments of EPA brownfield tax credits. Theadvantages and disadvantages ofbrownfield redevelopment must be care-fully considered during the site selectionprocess.

Utilize remediation experts to develop amaster plan for site remediation. Priori-tize site remediation activities based onavailable funds and specific site consider-ations, and establish time frames for com-pleting remediation activities. Test fortoxicity and hazardous levels of pollutionon the proposed site. To earn this credit,a site with existing hazardous substancespresent or potentially present must be se-lected, and remediation efforts must beperformed to identify, contain and miti-gate the hazard.

Clean the site using established technolo-gies that have minimal disruption on thenatural site features, both above groundand underground. Consider in-situremediation schemes that treat contami-nants in place instead of off-site. Onceremediation is complete, continue tomonitor the site for the identified con-taminants to ensure that contaminationproblems do not return.

Technologies

Remediation efforts on brownfield sitesare sometimes costly and time-intensivedue to the potentially extensive effort re-quired to characterize the contamination,evaluate cleanup options and performcleanup activities. However, substantiallylower property costs can offsetremediation costs and time delays. Thecost of remediation strategies varies by siteand region. Several remediation strate-gies should be considered in order to iden-tify the strategy with the greatest benefitand lowest cost to the property owner.

The appropriate technology for a specificsite depends on the contaminants present,

hydrogeologic conditions and other fac-tors. Traditional remediation efforts forcontaminated groundwater are termed“pump-and-treat.” Pump-and-treat tech-nologies involve pumping contaminatedgroundwater to the surface and treatingthe water using physical or chemical pro-cesses. Contaminated soils can beremediated in a variety of ways. Advancedtechnologies such as bioreactors and in-situ applications are sometimes more cost-effective than hauling large quantities ofcontaminated soil to an approved disposalfacility. Innovative remediation effortssuch as solar detoxification technologiesare currently being developed and are ex-pected to reduce remediation costs in thefuture. It is important to consider theenvironmental implications of allremediation strategies being investigatedfor your project to ensure the solutiondoes not cause problems elsewhere.


Brownfield redevelopment has an impacton all aspects of the site design and oftenworks in concert with urban redevelop-ment efforts. Existing infrastructure canlower development costs and take advan-tage of connections with neighboringsites. Some brownfield sites include ex-isting buildings that can be rehabilitated.However, it is always prudent to investi-gate potential contamination problemsand their effect on indoor air quality andoccupant health before selecting aremediation strategy.

Resources

Web Sites

Brownfields Non-Profits Network

www.brownfieldsnet.org,(717) 230-9700

A collection of nonprofit organizationsthat provide information on brownfieldredevelopment.

Credit 3


28

IDEASS WE MR EQ Brownfields Technology Support Center

www.brownfieldstsc.org

A public cooperative effort that providestechnical support to federal, state and lo-cal officials on items related to site inves-tigation and cleanup.

EPA Sustainable Redevelopment ofBrownfields Program

www.epa.gov/brownfields

A comprehensive site on brownfields thatincludes projects, initiatives, tools, taxincentives and other resources to addressbrownfield remediation and redevelop-ment. For information by phone, contactyour regional EPA office.

Print Media

ASTM Standard Practice E1739-95:Risk-Based Corrective Action Appliedat Petroleum Release Sites, AmericanSociety for Testing & Materials, (610)832-9585, www.astm.org

This document is a guide for risk-basedcorrective action (RBCA), a decision-making process that is specific to clean-ing up petroleum releases at contaminatedsites. It presents a tiered approach to siteassessment and remedial actions. It alsoincludes a comprehensive appendix withrisk calculations and sample applications.

EPA OSWER Directive 9610.17: Use ofRisk-Based Decision-Making in USTCorrection Action Programs, U.S. Envi-ronmental Protection Agency, Office ofUnderground Storage Tanks, www.epa.gov/swerust1/directiv/od961017.htm,(703) 603-7149

This document addresses the applicationof risk-based decision-making techniquesto properties where leaking undergroundstorage tanks (USTs) have created risksto human health and the environment.Guidelines are included to assist in mak-ing decisions in a manner consistent withfederal law, specifically CERCLA andRCRA programs. Risk-based decision-

making is a method that utilizes risk andexposure assessment methodology to de-termine the extent and urgency of cleanupactions. The goal is to protect humanhealth and the environment. This stan-dard includes several examples of stateprograms that use risk-based decision-making in leaking UST legislation.

Definitions

Bioremediation involves the use of mi-croorganisms and vegetation to removecontaminants from water and soils.Bioremediation is generally a form of in-situ remediation, and can be a viable al-ternative to landfilling or incineration.

CERCLA refers to the ComprehensiveEnvironmental Response, Compensation,and Liability Act (CERCLA), commonlyknown as Superfund. CERCLA addressesabandoned or historical waste sites andcontamination. It was enacted in 1980to create a tax on the chemical and petro-leum industries and provided federal au-thority to respond to releases of hazard-ous substances.

Ex-Situ Remediation involves the removalof contaminated soil and groundwater.Treatment of the contaminated media oc-curs in another location, typically a treat-ment facility. A traditional method of ex-situ remediation is pump-and-treat technol-ogy that uses carbon filters and incinera-tion. More advanced methods of ex-situremediation include chemical treatment orbiological reactors.

In-Situ Remediation involves treatmentof contaminants in place using technolo-gies such as injection wells or reactivetrenches. These methods utilize the natu-ral hydraulic gradient of groundwater andusually require only minimal disturbanceof the site.

RCRA refers to the Resource Conserva-tion and Recovery Act. RCRA focuseson active and future facilities. It was en-acted in 1976 to give the EPA authority

Credit 3


29

IDEASS WE MR EQ

Credit 3

to control hazardous wastes from cradleto grave, including generation, transpor-tation, treatment, storage and disposal.Some non-hazardous wastes are also cov-ered under RCRA.

Remediation is the process of cleaning upa contaminated site by physical, chemicalor biological means. Remediation processesare typically applied to contaminated soiland groundwater.

Risk Assessment is a methodology usedto analyze for potential health effects

Case Study

Pennsylvania Department of Environmental Protection’sSouth Central Regional Office BuildingHarrisburg, Pennsylvania

The Pennsylvania Department of Environmental Protection’sSouth Central Regional Office Building is a LEED™ BronzePilot Project that uses environmentally friendly technologies tosignificantly reduce energy consumption while creating a pro-ductive office atmosphere. The building is located on a site for-merly used for various industrial and municipal activities. In the1950s, the 13.5-acre site was quarried for shale. The site wasconverted into a municipal waste disposal facility in the 1960sand 1970s before being abandoned until the late 1990s. ThePennsylvania Department of Environmental Protection chose toredevelop the site to take advantage of the urban location and thedepressed property cost. Remediation efforts included cappingthe entire site and installing methane and leachate collection sys-tems to manage contaminant volumes leaving the site.

Owner909 Partners

Courtesy of Pennsylvania Department of Environmental Protection

caused by contaminants in the environ-ment. Information from the risk assess-ment is used to determine cleanup levels.

A Site Assessment is an evaluation ofabove-ground (including facilities) andsubsurface characteristics, including thegeology and hydrology of the site, to de-termine if a release has occurred, as wellas the extent and concentration of the re-lease. Information generated during a siteassessment is used to support remedialaction decisions.


30

IDEASS WE MR EQ

Credit 3


31

IDEASS WE MR EQ

Credit 4.1Alternative TransportationPublic Transportation Access

Intent

Reduce pollution and land development impacts from automobile use.

Requirements

Locate project within 1/2 mile of a commuter rail, light rail or subway station or 1/4mile of two or more public or campus bus lines usable by building occupants.

Submittals

❏ Provide the LEED Letter Template, signed by an appropriate party, declaring thatthe project building(s) are located within required proximity to mass transit.

❏ Provide an area drawing or transit map highlighting the building location and thefixed rail stations and bus lines, and indicate the distances between them. Includea scale bar for distance measurement.

1 point


32

IDEASS WE MR EQ

Alternative TransportationBicycle Storage and Changing Rooms

Intent


Requirements

For commercial or institutional buildings, provide secure bicycle storage with conve-nient changing/shower facilities (within 200 yards of the building) for 5% or more ofregular building occupants. For residential buildings, provide covered storage facilitiesfor securing bicycles for 15% or more of building occupants in lieu of changing/showerfacilities.

Submittals

❏ For commercial projects: provide the LEED Letter Template, signed by the Archi-tect or responsible party, declaring the distance to bicycle storage and showersfrom the building entrance and demonstrating that these facilities can accommo-date at least 5% of building occupants.

OR

❏ For residential projects: provide the LEED Letter Template, signed by the archi-tect or responsible party, declaring the design occupancy for the buildings, num-ber of covered bicycle storage facilities for securing bicycles, and demonstratingthat these facilities can accommodate at least 15% of building occupants.

Credit 4.2

1 point


33

IDEASS WE MR EQ

Credit 4.3Alternative TransportationAlternative Fuel Vehicles

Intent


Requirements

Provide alternative fuel vehicles for 3% of building occupants AND provide preferredparking for these vehicles, OR install alternative-fuel refueling stations for 3% of thetotal vehicle parking capacity of the site. Liquid or gaseous fueling facilities must beseparately ventilated or located outdoors.

Submittals

❏ Provide the LEED Letter Template and proof of ownership of, or 2 year leaseagreement for, alternative fuel vehicles and calculations indicating that alternativefuel vehicles will serve 3% of building occupants. Provide site drawings or parkingplan highlighting preferred parking for alternative fuel vehicles.

OR

❏ Provide the LEED Letter Template with specifications and site drawings high-lighting alternative-fuel refueling stations. Provide calculations demonstrating thatthese facilities accommodate 3% or more of the total vehicle parking capacity.

1 point


34

IDEASS WE MR EQ

Credit 4.4 Alternative TransportationParking Capacity

Intent

Reduce pollution and land development impacts from single occupancy vehicle use.

Requirements

Size parking capacity to meet, but not exceed, minimum local zoning requirementsAND provide preferred parking for carpools or vanpools capable of serving 5% of thebuilding occupants; OR add no new parking for rehabilitation projects AND providepreferred parking for carpools or vanpools capable of serving 5% of the building occu-pants.

Submittals

❏ For new projects: provide the LEED Letter Template, signed by the civil engineeror responsible party, stating any relevant minimum zoning requirements and de-claring that parking capacity is sized to meet, but not exceed them. State the num-ber of preferred parking spaces for carpools.

OR

❏ For rehabilitation projects: provide the LEED Letter Template, signed by the civilengineer or responsible party, declaring that no new parking capacity has beenadded.State the number of preferred parking spaces for carpools.



1 point


35

IDEASS WE MR EQ

Credit Synergies









WE Credit 2Innovative WastewaterTreatment

EA Prerequisite 1Fundamental BuildingSystems Commissioning

EA Credit 1Optimize EnergyPerformance

EA Credit 3AdditionalCommissioning

EA Credit 5Measurement &Verification



Credit 4Green Building ConcernsAs of the late 1990s, an estimated 200million of the 520 million cars worldwidewere located in the United States. Theinfrastructure (roadways and parking lots)used by automobiles dissects open ex-panses that wildlife relies on for migra-tion and foraging. This impervious in-frastructure also contributes to the ero-sion and pollution of receiving waters.The exhaust from automobiles pollutesthe air and contributes to acid rain. En-vironmental impacts occur during extract-ing, refining and transporting crude oilfor gasoline production. Reducing pri-vate automobile use saves energy and re-duces associated environmental problems.

Fortunately, alternatives to conventionaltransportation methods exist. A surpris-ingly large number of people are willingto use alternative means of transportationsuch as bicycles, mass transit and carpoolsif they are convenient and facilities areprovided to encourage their use. Alter-native fuel vehicles lessen environmentalimpacts associated with automobiles.These vehicles use non-gasoline-basedfuels such as electricity, natural gas andhydrogen-powered fuel cells. As a result,they require special refueling facilities tobe viable alternatives to conventional ve-hicles.

Parking facilities for automobiles also havenegative impacts on the environment be-cause asphalt surfaces increase stormwaterrunoff and contribute to urban heat is-land effects. By restricting the size of park-ing lots and promoting carpooling activi-ties, building occupants can benefit fromincreased green space.


Reduction of private automobile use re-duces fuel consumption and the associ-ated release of air and water pollutants invehicle exhaust. Alternative fuel vehicles

offer the possibility of reducing air pol-lutants from conventional gasoline-pow-ered vehicles as well as reducing the envi-ronmental effects of producing gasoline.It is important to remember that vehiclesusing fuels such as natural gas and elec-tricity still cause pollution at the tailpipeor power plant and are not otherwise en-vironmentally benign. The use of elec-tric vehicles eliminates tailpipe exhaustand centralizes the source of emissions atpower plants, where emissions can be bet-ter controlled. According to the U.S.DOE, compressed natural gas vehicleemissions are 80% less than those fromgasoline-powered vehicles.

Parking lots produce stormwater runoffand contribute to the urban heat islandeffect. They also diminish green spaceon the project site. Minimizing parkinglot size reduces the development footprintand sets aside more space for natural ar-eas or greater development densities.

Economic Issues

Reducing the size of parking areas basedon anticipated use of bicycles, carpoolsand public transit by building occupantsmay lower initial project costs. If localutilities charge for stormwater runoffbased on impervious surface area, mini-mization of these areas can result in lowerstormwater charges.

The initial cost to design and construct aproject in proximity to mass transit var-ies widely. During the site selection pro-cess, project owners should compare thecost of building sites in different areas todetermine if a reduction in automobileuse is possible and economical. Many oc-cupants view proximity to mass transit asa benefit and this can influence the valueand marketability of the building. Park-ing infrastructure and transportation re-quirements, disturbance of existing habi-tats, resource consumption, and futurefuel costs should also be assessed.


36

IDEASS WE MR EQ

Credit 4

The initial project cost increase for bikestorage areas and changing facilities isnominal relative to the overall project cost.Initial costs for alternative vehicles arehigher than for conventional vehicles andthis may delay their purchase, decreasingthe necessity for refueling stations. Dif-ferent alternative fuel vehicles need dif-ferent refueling stations, and the costs as-sociated with these stations vary.

Community Issues

Building occupants can realize health ben-efits through bicycle and walking com-muting strategies. Bicycling and walkingalso expose people to the community,encouraging interaction among neighborsand allowing for enjoyment of the area inways unavailable to automobile passen-gers.

Electric vehicle engines do not contrib-ute to noise pollution relative to internalcombustion engines. Alternative fuel ve-hicles have low, or no, tailpipe emissions.Aside from health benefits, lower emis-sions can help cities meet federal regula-tions and qualify for transportation fund-ing.

Design Approach

Strategies

Survey potential building occupants anddetermine if the available mass transpor-tation options meet their needs. Use ex-isting transportation networks to mini-mize the need for new transportationlines. Provide attractive, functional anddirect sidewalks, paths and walkways toexisting mass transit stops. Provide in-centives such as transit passes to encour-age occupants to use mass transit. En-courage employees to work from home ifpractical and design the building to ac-count for the needs of telecommuting.

Design and construct safe bicycle path-ways and secure bicycle storage areas for

cyclists. Provide shower and changingareas for cyclists that are easily accessiblefrom bicycle storage areas. For multifam-ily residential buildings, provide safe, eas-ily accessible and adequately sized bicycleracks. Encourage carpooling through ini-tiatives such as preferred parking areas forhigh-occupancy vehicles (HOV) and theelimination of parking subsidies for non-carpool vehicles. Explore the possibilityof sharing facilities with other groups forparking, shuttles and bike paths. Installan adequate number of easy-to-use refu-eling stations for alternative fuel vehicles.For residential buildings, consider estab-lishing carsharing programs.

Technologies

A variety of bicycle rack and locker prod-ucts are currently available. The appro-priate type and number of bicycle facili-ties depends on the number of bicyclistsand the climate of the region.

The U.S. DOE defines alternative fuelsas those that are substantially non-petro-leum and yield energy security and envi-ronmental benefits. DOE recognizes thefollowing as alternative fuels: methanoland denatured ethanol as alcohol fuels(alcohol mixtures that contain no less than70% of the alcohol fuel), natural gas(compressed or liquefied), liquefied pe-troleum gas, hydrogen, fuels derived frombiological materials, and electricity (in-cluding solar energy). Efficient gas-elec-tric hybrid vehicles are included in thisgroup for LEED purposes.

Electric vehicles (EVs) require a receptaclespecifically designed for this purpose, usu-ally 240 volts. EVs with conventionallead-acid batteries require recharging af-ter 50 miles. Refueling stations for natu-ral gas vehicles have compressors and dis-pensers that deliver compressed naturalgas (CNG) at about 3,000 psi.


37

IDEASS WE MR EQ

Credit 4


Transportation planning is affected by siteselection and has a significant impact onsite design. A building site near transitlines may have negative characteristics,such as site contamination, poor air qual-ity, unsafe conditions or problematicdrainage. Real estate costs may also behigher in areas close to transit lines.

Provisions for carpooling and the use ofbicycles as a viable transportation modefor building occupants reduce the needfor more parking spaces, thus reducingthe need for impervious surfaces and po-tential water runoff problems. A reduc-tion in hard surface parking areas couldalso increase the amount of open spaceon the site while reducing heat island ef-fects and stormwater runoff volumes.

Shower and changing facilities can addto the building’s footprint or decreaseother usable building space. These facili-ties also increase water and material us-age. While alternative fuel vehicles havelower impacts on the environment thanconventional vehicles, they require energyand materials to produce, as well as landarea for storage and mobility. Alterna-tive fuel refueling stations require energyfor operation as well as commissioningand measurement and verification atten-tion.

Space allocation and installation of refu-eling stations may not be cost-effectivewithout enough vehicles that require re-fueling at such stations. Building spacemay come at a premium, especially inprojects rehabilitating existing buildings.Investigate the possibility of sharing fa-cilities with other partners and businesses.

Calculations

The following calculation methodologyis used to support the credit submittals.

Mass Transit

Use an area drawing to indicate mass tran-sit stops within 1/2 mile of the project.

Remember that the project is required tobe within 1/2 mile of a commuter rail,light rail or subway station or within 1/4mile of two or more bus lines. Figure 1shows two bus lines within 1/4 mile ofthe project location. The map includes ascale bar and a north indicator.

If private shuttle buses will be used tomeet the requirements, they must con-nect to public transit and operate at leastduring the most frequent commutinghours.

Bicycle-Securing Apparatus andChanging/Showering Facilities

To determine the number of secure bi-cycle spaces and changing/showering fa-cilities required for the building, followthe calculation methodology as follows:

1. Identify the total number of full-timeand part-time building occupants.

2. Calculate the Full-Time Equivalent(FTE) building occupants based on astandard eight-hour workday. A full-timeworker has an FTE value of 1.0 while ahalf-time worker has a FTE value of 0.5(see Equation 1).

3. Total the FTE values for each shift toobtain the total number of FTE buildingoccupants. In buildings that house com-panies utilizing multiple shifts, select theshift with the greatest number of FTEbuilding occupants.

4. The minimum number of secure bi-cycle spaces required is equal to 5% ofthe FTE building occupants during themaximum shift (see Equation 2). Securebicycle spaces include bicycle racks, lock-ers and storage rooms. These spaces mustbe easily accessible by building occupantsduring all periods of the year, and free ofcharge.

5. The required number of changing andshowering facilities for non-residentialbuildings is based on the number of bi-cycling occupants. A minimum of oneshower for every eight bicycling occupants


38

IDEASS WE MR EQ

Credit 4

is required to earn this point. (This num-ber is based on recommended showeringfacilities for institutional spaces). Show-ering facilities can be unit showers orgroup showering facilities (see Equation3). This calculation is not necessary forresidential buildings.

For example, a building houses a com-pany with two shifts. The first shift in-cludes 240 full-time workers and 90 half-time workers. The second shift includes110 full-time workers and 60 part-timeworkers. Calculations to determine the

total FTE building occupants for eachshift are included in Table 1.

The first shift is used for determining thenumber of bicycling occupants becauseit has the greatest FTE building occupanttotal. Based on a total of 285 FTE build-ing occupants, the estimated number ofbicycling occupants is 15. Thus, 15 se-cure bicycle spaces are required for thisexample. The required number of chang-ing and showering facilities is one facilityfor every eight bicycling occupants. Thus,total number of required showering fa-cilities in this example is two. More show-ers may be necessary for the buildingbased on the number of actual bicyclingoccupants.Equation 1:

north

�

�

��

Figure 1: Sample Area Drawing

scale:0’ 200’

]hours[

]hours[HourskerWorFTE

8=


39

IDEASS WE MR EQ

Alternative Fuel Refueling Stations

To calculate the number of vehicles re-quired to be serviced by alternative fuelrefueling stations, multiply the total num-ber of vehicle parking spaces by 3% (seeEquation 4).

In the example above, the building has aparking area with 250 parking spaces.Therefore, alternative fuel refueling sta-tions are required to service 3% of the250 parking spaces, or eight vehicles. Therequired number of refueling stations de-pends on the number of vehicles (eight,in this case) and the service limits of thestation (the time necessary for each com-plete refueling multiplied by the numberof AFVs defined by Equation 4) in com-bination with the station’s operatinghours (i.e., if all vehicles are refueledwithin a short timeframe, or an eight-hour day, or nonstop).

Table 1: Sample FTE Calculation

Equation 3:

Equation 5:

Equation 4:

Equation 2:

ShiftFull-Time Equivalent

(FTE) Occupants

Occupants [hr] Occupants [hr] Occupants

First Shift 240 8 90 4 285

Second Shift 110 8 60 4 140

Full-TimeOccupants

Part-TimeOccupants

%xBuildingFTE

OccupantsSecure Bicycle Spaces(non-residential buildings)

Secure Bicycle Spaces(residential buildings)

5=

%xBuildingFTE

Occupants15=

8

SpacesBicylingShowering Facilities(non-residential buildings)

=

%ParkingTotal

SpacesMinimum Vehicle

Refueling Capacity3×=

2

5%OccupantsBuildingFTEofNumberquiredReSpacesCarpool

×=

Carpool Spaces

To calculate the number of carpool spacesrequired, multiply the number of FTE build-ing occupants during the maximum shift (seethe bicycle calculations above) by 5% anddivide by two occupants per vehicle (seeEquation 5). In the example above, a totalof 285 FTE building occupants requires aminimum of eight carpool spaces.

Resources

Web Sites

Advanced Transportation TechnologyInstitute

www.etvi.org, (423) 622-3884

A nonprofit organization that advancesclean transportation technologies throughresearch, education and technology trans-fer in order to promote a healthy envi-ronment and energy independence.

Credit 4


40

IDEASS WE MR EQ

Credit 4

Alternative Fuels Data Center

www.afdc.doe.gov, (800) 423-1363

A section of the DOE Office of Transpor-tation Technologies that has information onalternative fuels and alternative fuel vehicles,a locator for alternative refueling stations,and other related information.

Electric Auto Association

www.eaaev.org

A nonprofit education organization thatpromotes the advancement and widespreadadoption of electric vehicles.

Electric Vehicle Association of theAmericas

www.evaa.org, (202) 508-5924

An industry association that promoteselectric vehicles through policy, informa-tion and market development initiatives.

EV World

www.evworld.com

A Web site with current events, productreviews and other information related toelectric vehicles.

Natural Gas Vehicle Association

www.ngvc.org, (202) 824-7360

An organization consisting of natural gascompanies, vehicle and equipment manu-facturers, service providers, environmen-tal groups, and government organizationsto promote the use of natural gas for trans-portation.

Print Media

Alternative Fuels: Technology & Devel-opments, Society of Automotive Engi-neers, 1997.

Definitions

Alternative Fuel Vehicles are vehicles thatuse low-polluting, non-gasoline fuels suchas electricity, hydrogen, propane or com-pressed natural gas, liquid natural gas,methanol, and ethanol. Efficient gas-elec-tric hybrid vehicles are included in thisgroup for LEED purposes.

A Carpool is an arrangement in whichtwo or more people share a vehicle fortransportation.

Mass Transit includes transportation fa-cilities designed to transport large groupsof persons in a single vehicle such as busesor trains.

Public Transportation is bus, rail orother transportation service for the gen-eral public on a regular, continual basisthat is publicly or privately owned.


41

IDEASS WE MR EQ

Case Study

PNC Firstside CenterPittsburgh, Pennsylvania

The PNC Firstside Center is a LEED™ Silver Project that func-tions as a banking facility. To assess transportation planning is-sues, the project team polled future building occupants to deter-mine the percentage of occupants who would use personal ve-hicles, carpools, mass transportation, and other forms of trans-portation such as bicycles and walking. The owner used datafrom the poll to influence the local transit authority to constructa future mass transit stop adjacent to the building. Until thetransit stop is in operation, building occupants are utilizing 11bus routes located within _ mile of the building. The site islocated adjacent to a city bikeway and the building has bicycleracks to accommodate 60 bicycles, as well as showering and chang-ing facilities. Eight electric vehicle recharging stations have beeninstalled for building occupants using personal vehicles. Finally,the owner reached agreement with the local parking authority toshare a portion of a public 1200-space multilevel parking facilitylocated across the street.

OwnerPNC Bank

Courtesy of Paladino Consulting LLC

Credit 4


42

IDEASS WE MR EQ

Credit 4


43

IDEASS WE MR EQ

Reduced Site DisturbanceProtect or Restore Open Space

Intent

Conserve existing natural areas and restore damaged areas to provide habitat and pro-mote biodiversity.

Requirements

On greenfield sites, limit site disturbance including earthwork and clearing of vegeta-tion to 40 feet beyond the building perimeter, 5 feet beyond primary roadway curbs,walkways and main utility branch trenches, and 25 feet beyond constructed areas withpermeable surfaces (such as pervious paving areas, stormwater detention facilities andplaying fields) that require additional staging areas in order to limit compaction in theconstructed area; OR, on previously developed sites, restore a minimum of 50% of thesite area (excluding the building footprint) by replacing impervious surfaces with na-tive or adapted vegetation.

Submittals

❏ For greenfield sites: provide the LEED Letter Template, signed by the civil engi-neer or responsible party, demonstrating and declaring that site disturbance (in-cluding earthwork and clearing of vegetation) has been limited to 40 feet beyondthe building perimeter, 5 feet beyond primary roadway curbs, walk ways and mainutility branch trenches, and 25 feet beyond constructed areas with permeable sur-faces. Provide site drawings and specifications highlighting limits of constructiondisturbance.

OR

❏ For previously developed sites: provide a LEED Letter Template, signed by thecivil engineer or responsible party, declaring and describing restoration of degradedhabitat areas. Include highlighted site drawings with area calculations demonstrat-ing that 50% of the site area that does not fall within the building footprint hasbeen restored.

Credit 5.1

1 point


44

IDEASS WE MR EQ

Reduced Site DisturbanceDevelopment Footprint

Intent

Conserve existing natural areas and restore damaged areas to provide habitat and pro-mote biodiversity.

Requirements

Reduce the development footprint (defined as entire building footprint, access roadsand parking) to exceed the local zoning’s open space requirement for the site by 25%.For areas with no local zoning requirements (e.g., some university campuses and mili-tary bases), designate open space area adjacent to the building that is equal to thedevelopment footprint.

Submittals

❏ Provide a copy of the local zoning requirements highlighting the criteria for openspace. Provide the LEED Letter Template, signed by the civil engineer or respon-sible party, demonstrating and declaring that the open space exceeds the localzoning open space requirement for the site by 25%.

OR

❏ For areas with no local zoning requirements (e.g., some university campuses andmilitary bases), designate open space area adjacent to the building that is equal tothe development footprint. Provide a letter from the property owner stating thatthe open space will be conserved for the life of the building.



Credit 5.2

1 point


45

IDEASS WE MR EQ

Credit 5

Credit Synergies











WE Credit 3Water Use Reduction

EA Credit 2Renewable Energy

MR Prerequisite 1Storage & Collection ofRecyclables




Green Building ConcernsDevelopment of greenfield or undevel-oped areas disturbs and destroys wildlifeand plant habitat as well as wildlife corri-dors that allow animal migration. As ani-mals are pushed out of existing habitat,they become increasingly crowded intosmaller spaces. Eventually, their popula-tion exceeds the carrying capacity of thesespaces and they begin to invade surround-ing developments or perish due to over-population. Overall biodiversity, as wellas individual plant and animal species,may be threatened by reduction of habi-tat areas. Minimizing site disturbancereduces habitat destruction.


The construction process is often dam-aging to site ecology, indigenous plantsand regional animal populations. Eco-logical site damage can be avoided orminimized by limiting the extent of con-struction activities to certain areas on thesite and by restricting the developmentfootprint to the greatest extent possible.Protection of open space and sensitive ar-eas through the use of strict boundariesreduces damage to the site ecology, result-ing in preservation of wildlife corridorsand habitat.

Economic Issues

Preserving topsoil, plants and trees on thesite can reduce landscaping costs for thebuilding and increase property values. In-digenous plantings often require less main-tenance than exotic plantings and minimizeinputs of fertilizers, pesticides, and water,reducing maintenance costs over the build-ing lifetime. In some cases, trees and veg-etation developed as specimens off-site arecostly to purchase and may not survivetransplanting. Purchasing and installingnew plants can add to project cost. Savingexisting site vegetation to replant after con-struction is complete may be a more cost-effective strategy.

Reducing the footprint of a structure ona given site can have varying economicimpacts. Building a vertical structure withthe same square footage as a horizontalstructure may add a small percentage tofirst costs depending on building size anduse. A structure with a smaller footprintis generally more resource-efficient, result-ing in reduced material and energy costs.A more compact building with coordi-nated infrastructure can reduce initialproject costs, as well as operations andmaintenance costs. Reduced earthwork,shorter utility lines, and reduced surfaceparking and paved areas all can reduce ini-tial project costs. Compact paving areasand buildings reduce operations andmaintenance costs.

Design Approach

Strategies

Design a master plan for the project area,survey existing ecosystems and identifysoil types on the site. Document existingwater elements, soil conditions, ecosys-tems, wildlife corridors, trees and othervegetation, and map all potential naturalhazards. Consider the impacts of the pro-posed development on existing naturaland built systems and propose strategiesto mitigate negative impacts.

Choose a building footprint and locationthat minimize disturbance to the existingecosystem. Consider issues such as build-ing orientation, daylighting, heat islandeffects, stormwater generation, significantvegetation and other sustainable buildingissues. Once the site and building loca-tion have been determined, design andconstruct a compact parking, road andbuilding footprint layout in order to pre-serve open land. Reduce footprints bytightening program needs and stackingfloor plans.

Encourage preservation, conservation andrestoration of existing natural site ameni-ties. Where appropriate, build on parts


46

IDEASS WE MR EQ

Credit 5

of the site that are already degraded so asnot to degrade undisturbed areas. Restorethe native landscape of the site by pre-serving and planting native species to re-establish predevelopment site conditions.Restoration efforts will vary depending onthe particular project site.

Volunteer efforts can reduce the cost ofsaving existing trees and plants. For ex-ample, a volunteer “plant rescue” effortwas organized on the site of the new EPAcomplex in Research Triangle Park, NorthCarolina. Assisted by the neighboringNational Institutes for EnvironmentalHealth Sciences and the North CarolinaBotanical Gardens at Chapel Hill, thiseffort saved more than 2,000 plants thatwere transplanted elsewhere on the siteor sent to other locations. A variety oflocal plant amnesty organizations existthat can help with plant and tree preser-vation and relocation.

During the construction process, estab-lish clearly marked construction and dis-turbance boundaries and note these siteprotection requirements in constructiondocuments. Delineate lay down, recyclingand disposal areas, and use paved areasfor staging activities. Erect constructionfencing around the drip line of existingtrees to protect them from damage andsoil compaction by construction vehicles.Establish contractual penalties if destruc-tion of protected areas outside of the con-struction boundaries occurs. Coordinateinfrastructure construction to minimizethe disruption of the site and work withexisting topography to limit cut-and-fillefforts for the project.

For achievement of Credit 5.2 in areaswith no established zoning requirementsfor open space, a project must show thatan open space area equal to the buildingfootprint has been established adjacent tothe building.


Balancing the verticality of a structurewith open space requirements can be achallenging exercise. For instance, shad-ing from tall structures may change theenvironmental character of the openspace, and these structures may be intimi-dating and unwelcoming to building oc-cupants. Furthermore, large expanses ofopen space may be a barrier to publictransportation access. Conversely, retain-ing a high proportion of open space veg-etation reduces stormwater runoff vol-umes and natural features may be avail-able for wastewater or stormwater treat-ment. Preservation of certain trees mayreduce passive solar gains. Check the sit-ing of the structure to optimize solar op-portunities and to preserve the most sig-nificant trees. Additional vegetation canassist with cooling breezes and noise re-duction, and enhance the site air quality.

The site location and site design have asignificant effect on open space and re-duced habitat disturbance. Heat islandeffects, stormwater generation, and lightpollution should all be considered whendetermining the site design. The land-scape design and irrigation scheme is in-timately tied with the site design and openspace allotted. In addition, water reuseand on-site wastewater treatment strate-gies have an effect on non-building spaces.

Renewable energy technologies such aswind turbines and biomass generationrequire site space. Rehabilitation of ex-isting buildings may dictate the amountof open space available. Constructionwaste management schemes may en-croach on natural areas for storage ofbuilding wastes earmarked for recycling.


47

IDEASS WE MR EQ

Credit 5Resources

Web Sites

North American Native Plant Society

www.nanps.org, (416) 631-4438

A nonprofit association dedicated to thestudy, conservation, cultivation and res-toration of native plants. Contains linksto state/provincial associations.

Soil and Water Conservation Society

www.swcs.org, (515) 289-2331

An organization focused on fostering thescience and art of sustainable soil, waterand related natural resource management.

Print Media

Beyond Preservation: Restoring and In-venting Landscapes by A. DwightBaldwin et al., University of MinnesotaPress, 1994.

Design for Human Ecosystems: Land-scape, Land Use, and Natural Resourcesby John Tillman Lyle and Joan Wood-ward, Milldale Press, 1999.

Landscape Restoration Handbook byDonald Harker, Lewis Publishers, 1999.

Definitions

The Building Footprint is the area on aproject site that is used by the buildingstructure and is defined by the perimeterof the building plan. Parking lots, land-scapes and other non-building facilitiesare not included in the building footprint.

The Development Footprint is the areaon the project site that has been impactedby any development activity. Hardscape,access roads, parking lots, non-buildingfacilities and building structure are all in-cluded in the development footprint.

A Greenfield is defined as undevelopedland or land that has not been impactedby human activity.

Local Zoning Requirements are localgovernment regulations imposed to pro-mote orderly development of private landsand to prevent land use conflicts.

Native/Adapted Plants are those that areindigenous to a locality or have adaptedto the local climate and are not invasive.Such plants do not require irrigation orfertilization once root systems are estab-lished in the soil.

Open Space Area is the property area mi-nus the development footprint. Openspace must be vegetated and pervious,thus providing habitat and other ecologi-cal services.


48

IDEASS WE MR EQ

Case Study

Kandalama HotelColombo, Sri Lanka

The Kandalama Hotel, a LEED™ Bronze Pilot Project, is a 162-bedroom resort hotel located on a picturesque site with densevegetation. The project site is an excellent example of how asensitive natural site can be thoughtfully developed to protectthe existing natural attributes. The design team chose to capital-ize on the natural amenities of the site by minimizing construc-tion extents and the overall building footprint. As a result, thetotal built area is only 10% of the total 55-acre site. Special ef-forts were made during construction to retain native vegetationand nestle the hotel into the existing lush trees and plants to pro-vide shading for the guest rooms, restaurants and garden areas. Asurvey of the density and distribution of flora was used to docu-ment the existing site characteristics and the building design wasaltered to preserve existing trees and the natural topography ofthe site. Stilts and columns were used to elevate the buildingsabove existing natural features such as boulders and to reducecut-and-fill needs.

OwnerKandalama Hotels Ltd.

Courtesy of Green Technologies, Inc.

Credit 5


49

IDEASS WE MR EQ

Stormwater ManagementRate and Quantity

Intent

Limit disruption and pollution of natural water flows by managing stormwater runoff.

Requirements

If existing imperviousness is less than or equal to 50%, implement a stormwater man-agement plan that prevents the post-development 1.5 year, 24 hour peak discharge ratefrom exceeding the pre-development 1.5 year, 24 hour peak discharge rate.

OR

If existing imperviousness is greater than 50%, implement a stormwater managementplan that results in a 25% decrease in the rate and quantity of stormwater runoff.

Submittals

❏ Provide the LEED Letter Template, signed by the civil engineer or responsibleparty, declaring that the post-development 1.5 year, 24 hour peak discharge ratedoes not exceed the pre-development 1.5 year 24 hour peak discharge rate. In-clude calculations demonstrating that existing site imperviousness is less than orequal to 50%.

OR

❏ Provide the LEED Letter Template, signed by the civil engineer or responsibleparty, declaring and demonstrating that the stormwater management strategiesresult in at least a 25% decrease in the rate and quantity of stormwater runoff.Include calculations demonstrating that existing site imperviousness exceeds 50%.

Credit 6.1

1 point


50

IDEASS WE MR EQ

Stormwater ManagementTreatment

Intent

Limit disruption of natural water flows by eliminating stormwater runoff, increasingon-site infiltration and eliminating contaminants.

Requirements

Construct site stormwater treatment systems designed to remove 80% of the averageannual post-development total suspended solids (TSS) and 40% of the average annualpost-development total phosphorous (TP) based on the average annual loadings fromall storms less than or equal to the 2-year/24-hour storm. Do so by implementing BestManagement Practices (BMPs) outlined in Chapter 4, Part 2 (Urban Runoff ), of theUnited States Environmental Protection Agency’s (EPA’s) Guidance Specifying Man-agement Measures for Sources of Nonpoint Pollution in Coastal Waters, January 1993(Document No. EPA-840-B-92-002) or the local government’s BMP document (which-ever is more stringent).

Submittals

❏ Provide the LEED Letter Template, signed by the civil engineer or responsibleparty, declaring that the design complies with or exceeds EPA or local governmentBest Management Practices (whichever set is more stringent) for removal of totalsuspended solids and total phosphorous.


Guidance Specifying Management Measures for Sources of Non-Point Pollutionin Coastal Waters, January 1993 (Document No. EPA 840B92002)

Internet location: www.epa.gov/owow/nps/MMGI

Hardcopy or microfiche (entire document, 836 pages): National Technical Informa-tion Service (order # PB93-234672), www.ntis.gov, (800) 553-6847

U.S. Environmental Protection Agency Office of Water, www.epa.gov/OW

This document discusses a variety of management practices that can be incorporatedto remove pollutants from stormwater volumes. Chapter 4, Part II addresses urbanrunoff and suggests a variety of strategies for treating and infiltrating stormwater vol-umes after construction is completed. See the Resources section later in this credit fora summary of best management practices listed in the EPA document.

Credit 6.2

1 point


51

IDEASS WE MR EQ

Credit 6

Credit Synergies










WE Credit 3Water Use Reduction


Green Building ConcernsThe volume of stormwater generatedfrom a site depends on the impervioussurface area. In natural settings, the ma-jority of precipitation infiltrates into theground while a small portion runs off onthe surface and into receiving waters. Thissurface runoff water is classified asstormwater runoff. As areas are con-structed and urbanized, surface perme-ability is reduced, resulting in increasedstormwater runoff volumes that are trans-ported via urban infrastructure (e.g., gut-ters, pipes and sewers) to receiving wa-ters. These stormwater volumes containsediment and other contaminants thathave a negative impact on water quality,navigation and recreation. Furthermore,conveyance and treatment of stormwatervolumes requires significant municipal in-frastructure and maintenance.

Reducing the generation of stormwatervolumes maintains the natural aquiferrecharge cycle. In addition, stormwatervolumes do not have to be conveyed toreceiving waters by the municipality, andreceiving waters are not impacted.


Reduction and treatment of runoff vol-umes decrease or eliminate contaminantsthat pollute receiving water bodies. Forinstance, parking areas contribute tostormwater runoff that is contaminatedwith oil, fuel, lubricants, combustion by-products, material from tire wear, and de-icing salts. Minimizing the need forstormwater infrastructure also reducesconstruction impacts and the overall eco-logical “footprint” of the building. Finally,infiltration of stormwater on-site can re-charge local aquifers, mimicking the natu-ral water cycle.

Economic Issues

If natural drainage systems are designedand implemented at the beginning of siteplanning, they can be integrated economi-cally into the overall development. Wa-ter detention and retention features re-quire cost for design, installation andmaintenance. However, these features canalso add significant value as site ameni-ties if planned early in the design. Waterfeatures may pose safety and liability prob-lems, especially in locations where youngchildren are playing outdoors. The useof infiltration devices such as perviouspaving may reduce water runoff collec-tion system costs.

Community Issues

Stormwater volume reduction leads toimproved watershed quality that benefitsthe community through improved waterquality, navigation and recreation activi-ties. Reduced stormwater collection andtreatment systems lessen the burden onmunicipalities for maintenance and repair,resulting in a more affordable and stabletax base.

Design Approach

Strategies

The most effective method to minimizestormwater runoff volume is to reduce theamount of impervious area. By reducingimpervious area, stormwater infrastruc-ture can be minimized or deleted fromthe project. To minimize impervious sur-faces and to encourage the natural pro-cesses of evaporation and infiltration, con-sider such methods as designing a smallerbuilding footprint, installing green roofsand paving with pervious materials.

Capture stormwater from impervious ar-eas to reuse within the building.Stormwater harvesting from roofs andhardscapes can be used for non-potable


52

IDEASS WE MR EQ

Credit 6

uses such as sewage conveyance, fire sup-pression and industrial applications.

For stormwater volumes that must beconveyed from the site to a receiving wa-ter body, design treatment practices tomatch the needs of the location and thespecific drainage area. Design stormwaterfacilities to remove contaminants and re-lease the volumes to local water bodies.Utilize biologically based and innovativestormwater management features for pol-lutant load reduction such as constructedwetlands, stormwater filtering systems,bioswales, bioretention basins, and veg-etated filter strips. Use vegetated buffersaround parking lots to remove runoffpollutants such as oil and grit. Specifyand install water quality structures forpretreatment of runoff from surface park-ing areas. Do not disturb existing wet-lands or riparian buffers when construct-ing ponds at the lowest elevations of a site.Design stormwater runoff to flow intovegetated swales rather than into struc-tured pipes for conveyance to water qual-ity ponds. Swales provide filtration forstormwater volumes and require lessmaintenance than constructedstormwater features. Install sequences ofponds whenever possible for more com-plete water treatment.

In some cases, such as heavily wooded siteswhere larger ponds are not feasible, dis-tribute smaller bioretention areas that use

subsurface compost and plantings to ac-celerate the filtering of contaminantsaround the site, instead of using one largepool. To moderate water runoff alongdrainage paths, construct water ponds totemporarily store stormwater flows.These ponds also improve water qualitythrough settling and biodegradation ofpollutants.

Technologies

Clustering or concentrating developmentsto reduce the amount of paved surfacessuch as roads, parking lots and sidewalksminimizes impervious surfaces. Widthsand lengths of roads, parking lots andsidewalks can also be minimized. For in-stance, turning lanes in roads can be re-moved to minimize the width of the pavedsurface. This requires the sharing of trav-eling and turning lanes.

Garden roofs or green roofs are vegetatedsurfaces that capture rainwater and returna portion of it back to the atmosphere viaevapotranspiration. They consist of alayer of plants and soil, a cup layer forcollection and temporary storage ofstormwater, and a synthetic liner to pro-tect the top of the building fromstormwater infiltration. Garden roofs alsoprovide insulating benefits and aestheticappeal. Some garden roofs require plantmaintenance and are considered activegardens while other garden roofs have

Table 1: Typical Runoff Coefficients

Surface TypeRunoff

CoefficientSurface Type Runoff

Coefficient

Pavement, Asphalt 0.95 Turf, Flat (0 - 1% slope) 0.25

Pavement, Concrete 0.95 Turf, Average (1 - 3% slope) 0.35

Pavement, Brick 0.85 Turf, Hilly (3 - 10% slope) 0.40

Pavement, Gravel 0.75 Turf, Steep (> 10% slope) 0.45

Roofs, Conventional 0.95 Vegetation, Flat (0 - 1% slope) 0.10

Roof, Garden Roof (< 4 in) 0.50 Vegetation, Average (1 - 3% slope) 0.20

Roof, Garden Roof (4 - 8 in) 0.30 Vegetation, Hilly (3 - 10% slope) 0.25

Roof, Garden Roof (9 - 20 in) 0.20 Vegetation, Steep (> 10% slope) 0.30

Roof, Garden Roof (> 20 in) 0.10


53

IDEASS WE MR EQ

Credit 6

grasses and plants that require no main-tenance or watering. All types of gardenroofs require semiannual inspection butare estimated to have a longer lifetime andrequire less maintenance than conven-tional roofs.

Pervious paving systems reducestormwater runoff by allowing precipita-tion to infiltrate the undersurface throughvoids in the paving material. These sys-tems can be applied to pedestrian trafficsurfaces as well as low-vehicle traffic ar-eas such as parking spaces, fire lanes, andmaintenance roads. Use pervious pavingmaterials such as poured asphalt or con-crete with incorporated air spaces or useconcrete unit paving systems with largevoids that allow grass or other vegetationto grow between the voids.

Pervious paving has several options, in-cluding systems that use grass and a plas-tic grid system (90% pervious), concretegrids with grass (40% pervious), and con-crete grids with gravel (10% pervious).Pervious paving requires different main-tenance procedures than impervious pave-ment. With some systems, vacuumsweeping is necessary to prevent the voidsfrom clogging with sediment, dirt andmud. Systems that use vegetation, suchas grass planted in a plastic matrix overgravel, may require mowing like conven-tional lawns. Snow removal from pervi-ous paving requires more care than fromconventional paving. Check existingcodes relating to the use of pervious sur-faces for roadways.

To earn the second portion of this credit,stormwater volumes leaving the site mustpass through a stormwater treatment sys-tem that removes total suspended solidsand phosphorous to the required levels.

Packaged stormwater treatment systemscan also be installed to treat stormwatervolumes. These systems use filters to re-move contaminants and can be sized forvarious stormwater volumes.


Stormwater runoff is affected significantlyby site selection and site design, especiallytransportation amenity design. It may bepossible to reuse stormwater fornonpotable water purposes such as flush-ing urinals and toilets, custodial applica-tions, and building equipment uses. Re-habilitation of an existing building mayaffect stormwater reduction efforts if largeimpervious surfaces already exist.

It is helpful to perform a water balance todetermine the estimated volumes of wa-ter available for reuse. Stormwater run-off volumes can also be reduced by de-signing the building with undergroundparking, a strategy that also reduces heatisland effects. Pervious paving systemsusually have a limit on transportationloads and may pose problems for wheel-chair accessibility and stroller mobility. Ifstormwater volumes are treated on site,additional site area may need to be dis-turbed to construct treatment ponds orunderground facilities. Application ofgarden roofs reduces stormwater volumesthat may be intended for collection andreuse for non-potable applications.

Calculations for Credit 6.1

The following calculation methodologyis used to support the credit submittalslisted on the first page of this credit.Stormwater runoff volumes are affectedby surface characteristics on the site as wellas rainfall intensity over a specified timeperiod. To simplify stormwater calcula-tions, consider only the surface charac-teristics of the project site. Stormwatervolumes generated are directly related tothe net imperviousness of the project site.By reducing the amount of impervioussurface on the site, stormwater volumesare reduced.

The calculation methodology to estimatethe imperviousness of the project site isas follows:


54

IDEASS WE MR EQ

Credit 6

1. Identify the different surface types onthe site: roof areas, paved areas (e.g., roadsand sidewalks), landscaped areas, andother areas.

2. Calculate the total area for each of thesesurface types using site drawings. UseTable 1 to assign a runoff coefficient toeach surface type. If a surface type is notincluded in the table, use a “best estimate”or manufacturer information. For in-stance, if pervious paving is used, consultthe manufacturer to determine the im-perviousness or percentage of the surfacethat does not allow infiltration.

3. Create a spreadsheet to summarize thearea and runoff coefficient for each sur-face type. Multiply the runoff coefficientby the area to obtain an impervious areafor each surface type. This figure repre-sents the square footage of each surfacearea that is 100% impervious (see Equa-tion 1).

4. Add the impervious areas for each sur-face type to obtain a total impervious areafor the site.

5. Divide the total impervious area by thetotal site area to obtain the impervious-ness of the site (see Equation 2).

Credit requirements state that for siteswith imperviousness less than or equal to50%, imperviousness must not increasefrom predevelopment to post-develop-ment conditions. For previously devel-oped sites with imperviousness greaterthan 50%, imperviousness must be re-duced by 25% from predevelopment topost-development conditions.

The following example describes the cal-culation method for site imperviousness.The example project is an office renova-tion and site improvements to an exist-ing concrete parking lot of average slope.Surface types include sidewalks, parkingareas, landscaping and the roof. The roof

Table 3: Baseline Case Imperviousness

Table 2: Design Case Imperviousness

Runoff Coefficient

AreaImpervious

Area

[SF] [SF]

0.95 5,075 4,821

0.60 1,345 807

0.30 8,240 2,472

0.20 4,506 901

TOTAL AREA 14,660

TOTAL IMPERVIOUS AREA 8,100

55%

Surface Type

IMPERVIOUSNESS

Pavement, Asphalt

Pavement, Pervious

Roof, Garden Roof (4 - 8 in)

Vegetation, Average (1 -3% slope)

Runoff Coefficient

AreaImpervious

Area

[SF] [SF]

0.95 19,166 18,208

TOTAL AREA 19,166

TOTAL IMPERVIOUS AREA 18,208

95%IMPERVIOUSNESS

Surface Type

Pavement, Concrete


55

IDEASS WE MR EQ

Credit 6

area is assumed to be equal to the build-ing footprint as determined from sitedrawings. Table 2 shows calculations forthe design case.

To reduce imperviousness, concrete side-walks and asphalt parking lots can be sub-stituted with pervious paving and vegeta-tion in some areas. The building foot-print is reduced and garden roofs are ap-plied to reduce roof runoff.

Next, calculations are done for thebaseline case or the existing site condi-tions (see Table 3). The original use ofthe site was for parking and, thus, theentire site was paved with concrete pave-ment.

The calculations demonstrate that thedesign case has an imperviousness of 47%and the baseline case has an impervious-ness of 95%—a 50% reduction that ex-ceeds the 25% required, thus earning onepoint.

Calculations for Credit 6.2

In most cases where projects choose toutilize standard EPA or local BMPs, nocalculations are required to demonstratecompliance with the requirements ofCredit 6.2. In instances where designsfar different than accepted BMPs havebeen developed and implemented, theLEED Letter Template along with de-tailed engineering calculations may berequired to demonstrate the TSS andphosphorus reductions that will beachieved.

Resources for Credit 6.2Below is a summary of stormwater bestmanagement practices from the EPA’sGuidance Specifying ManagementMeasures for Sources of Non-point Pol-lution in Coastal Waters. For more in-formation about this document, see Sum-mary of Referenced Standard earlier inthis credit.

Infiltration Basins and Trenches are de-vices used to encourage subsurface infil-tration of runoff volumes through tem-porary surface storage. Basins are pondsthat can store large volumes ofstormwater. They need to drain within72 hours to maintain aerobic conditionsand to be available for the next stormevent. Trenches are similar to infiltrationbasins except that they are shallower andfunction as a subsurface reservoir forstormwater volumes. Pretreatment to re-move sediment and oil may be necessaryto avoid clogging of infiltration devices.Infiltration trenches are more common inareas where infiltration basins are notpossible.

Porous Pavement and Permeable Sur-faces are used to create permeable surfacesthat allow runoff to infiltrate into the sub-surface. These surfaces are typically main-tained with a vacuuming regime to avoidpotential clogging and failure problems.

Vegetated Filter Strips and GrassedSwales utilize vegetation to filter sedimentand pollutants from stormwater. Stripsare appropriate for treating low-velocitysurface sheet flows in areas where runoff

Equation 1:

Equation 2:

RunofftCoefficien

]SF[SurfaceArea

]SF[perviousImArea

×=

]SF[AreaSiteTotal

]SF[AreaPerviousTotal[%]nessperviousIm =


56

IDEASS WE MR EQ

Credit 6

is not concentrated. They are often usedas pretreatment for other stormwatermeasures such as infiltration basins andtrenches. Swales consist of a trench orditch with vegetation and require occa-sional mowing. They also encourage sub-surface infiltration, similar to infiltrationbasins and trenches.

Filtration Basins remove sediment andpollutants from stormwater runoff usinga filter media such as sand or gravel. Asediment trap is usually included to re-move sediment from stormwater beforefiltering to avoid clogging.

Constructed Wetlands are engineeredsystems that are designed to mimic natu-ral wetland treatment properties. Ad-

vanced designs incorporate a wide vari-ety of wetland trees, shrubs, and plantswhile basic systems only include a lim-ited number of vegetation types.

Detention Ponds capture stormwaterrunoff and allow pollutants to drop outbefore release to a stormwater or waterbody. A variety of detention pond de-signs are available, with some utilizingonly gravity while others use mechanicalequipment such as pipes and pumps tofacilitate transport. Some ponds are dryexcept during storm events; others per-manently store water volumes.

Table 4 highlights the advantages, disad-vantages and removal efficiency rates forthe above stormwater control practices.

Table 4: EPA Best Management Practices

Practice Advantages Disadvantages

TSS(req. 80%)

TP(req. 40%)

Infiltration Basins & Infiltration Trenches

Provides groundwater recharge, high removal efficiency, provides habitat

Requires permeable soils, high potential for failure, requires maintenance

50 to 100 50 to 100

Porous Pavement Provides groundwater recharge, no space requirement, high removal efficiency

Requires permeable soils, not suitable for high-traffic areas, high potential for failure, requires

60 to 90 60 to 90

Vegetated Filter Strips Low maintenance, good for low-velocity flows, provides habitat, economical

Not appropriate for high-velocity flows, requires periodic repair and reconstruction

40 to 90 30 to 80

Grassy Swales Small land requirements, can replace curb and gutter infrastructure, economical

Low removal efficiency 20 to 40 20 to 40

Filtration Basins Provides groundwater recharge, peak volume control

Requires pretreatment to avoid clogging

60 to 90 0 to 80

Constructed Wetlands Good for large developments, peak volume control, high removal efficiency, aesthetic value

Not economical for small developments, requires maintenance, significant space requirements

50 to 90 0 to 80

Dry Ponds Peak flow control, less space and

cost vs. wet pond

Space, maintenance, limited soil groups 70 to 90 10 to 60

Wet Ponds

Source: EPA840B92002 Tables 4-5 and 4-7

Peak flow control, prevents scour

and resuspension

Space, cost, maintenance, limited

soil groups

50 to 90 20 to 90

RemovalEfficiency [%]

maintenance


57

IDEASS WE MR EQ

Credit 6

Other technologies may also satisfy thecredit’s performance requirements.

Definitions

A Constructed Wetland is an engineeredsystem designed to simulate natural wet-land functions for water purification.Constructed wetlands are essentially treat-ment systems that remove contaminantsfrom wastewaters.

Impervious Surfaces promote runoff ofprecipitation volumes instead of infiltrationinto the subsurface. The imperviousnessor degree of runoff potential can be esti-mated for different surface materials.

Stormwater Runoff consists of water vol-umes that are created during precipitation

Case Study

Philips Eco-Enterprise CenterMinneapolis, Minnesota

The Phillips Eco-Enterprise Center is a mixed-use building thathouses environmental and energy efficiency organizations, con-sultants and manufacturers. The landscape on the project sitewas designed using xeriscape principles and requires no irriga-tion volumes. The native prairie grasses and wildflowers survivesolely on precipitation. Stormwater that is not used by the plantsor infiltrated into the subsurface is treated in a restored wetlandand enhanced bio-filtration system. The system removes oil andsediment from stormwater and diverts 1.5 million gallons of run-off from entering the municipal stormwater system annually. Fi-nally, a 4,000-square-foot section of the roof was designed as agarden roof to reduce stormwater runoff, provide superior insu-lation, and create a natural area that building occupants mayenjoy.

OwnerThe Green Institute

Courtesy of Paladino Consulting LLC

events and flow over surfaces into sewersystems or receiving waters. All precipi-tation waters that leave project site bound-aries on the surface are considered to bestormwater runoff volumes.

Total Phosphorous (TP) consists of or-ganically bound phosphates, poly-phos-phates and orthophosphates instormwater, the majority of which origi-nates from fertilizer application. Chemi-cal precipitation is the typical removalmechanism for phosphorous.

Total Suspended Solids (TSS) are par-ticles or flocs that are too small or light tobe removed from stormwater via gravitysettling. Suspended solid concentrationsare typically removed via filtration.


58

IDEASS WE MR EQ

Credit 6


59

IDEASS WE MR EQ

Heat Island EffectNon-Roof

Intent

Reduce heat islands (thermal gradient differences between developed and undevelopedareas) to minimize impact on microclimate and human and wildlife habitat.

Requirements

Provide shade (within 5 years) and/or use light-colored/high-albedo materials (reflec-tance of at least 0.3) and/or open grid pavement for at least 30% of the site’s non-roofimpervious surfaces, including parking lots, walkways, plazas, etc.; OR place a mini-mum of 50% of parking spaces underground or covered by structured parking; ORuse an open-grid pavement system (less than 50% impervious) for a minimum of 50%of the parking lot area.

Submittals

❏ Provide the LEED Letter Template, signed by the civil engineer or responsibleparty, referencing the site plan to demonstrate areas of paving, landscaping (listspecies) and building footprint, and declaring that:

❏ A minimum of 30% of non-roof impervious surfaces areas are constructedwith high-albedo materials and/or open grid pavement and/or will be shadedwithin five years

❏ OR a minimum of 50% of parking spaces have been placed underground orare covered by structured parking

❏ OR an open-grid pavement system (less than 50% impervious) has been usedfor a minimum of 50% of the parking lot area.

Credit 7.1

1 point


60

IDEASS WE MR EQ

Heat Island EffectRoof

Intent

Reduce heat islands (thermal gradient differences between developed and undevelopedareas) to minimize impact on microclimate and human and wildlife habitat.

Requirements

Use ENERGY STAR® compliant (highly reflective) AND high emissivity roofing (emis-sivity of at least 0.9 when tested in accordance with ASTM 408) for a minimum of75% of the roof surface; OR install a “green” (vegetated) roof for at least 50% of theroof area. Combinations of high albedo and vegetated roof can be used providing theycollectively cover 75% of the roof area.

Submittals

❏ Provide the LEED Letter Template, signed by the architect, civil engineer or re-sponsible party, referencing the building plan and declaring that the roofing mate-rials comply with the ENERGY STAR® Label requirements and have a minimumemissivity of 0.9. Demonstrate that high-albedo and vegetated roof areas com-bined constitute at least 75% of the total roof area.

OR

❏ Provide the LEED Letter Template, signed by the architect, civil engineer or re-sponsible party, referencing the building plan and demonstrating that vegetatedroof areas constitute at least 50% of the total roof area.


ASTM E408-71(1996)e1—Standard Test Methods for Total Normal Emittance ofSurfaces Using Inspection-Meter Techniques, www.astm.org, (610) 832-9585

This standard describes how to measure total normal emittance of surfaces using aportable inspection-meter instrument. The test methods are intended for large sur-faces where non-destructive testing is required. See the standard for testing steps and adiscussion of thermal emittance theory.

ASTM E903-96—Standard Test Method for Solar Absorptance, Reflectance, andTransmittance of Materials Using Integrating Spheres, www.astm.org,(610) 832-9585

Referenced in the ENERGY STAR roofing standard, this test method uses spectropho-tometers and need only be applied for initial reflectance measurement. Methods ofcomputing solar-weighted properties from the measured spectral values are specified.This test method is applicableto materials having both specular and diffuse opticalproperties.Except for transmitting sheet materials that are inhomogeneous, patterned,or corrugated, this test method is preferred over Test Method E1084.

The ENERGY STAR roofing standard also allows the use of reflectometers to measuresolar reflectance of roofing materials. See the roofing standard for more details.

Credit 7.2

1 point


61

IDEASS WE MR EQ

Credit 7

EPA Energy Star Roofing Guidelines

U.S. Environmental Protection Agency ENERGY STAR® Program, www.energystar.gov,(888) 782-7937

The EPA’s ENERGY STAR program allows for voluntary partnerships between the U.S.Department of Energy, the U.S. Environmental Protection Agency, product manufac-turers, local utilities, and retailers. ENERGY STAR is dedicated to promoting energy effi-ciency, reducing air pollution, and saving money for businesses and residences throughdecreased energy use. In addition to several other building product categories, theENERGY STAR program identifies roofing products that reduce the amount of air-condi-tioning needed in buildings, and can reduce energy bills by up to 50% (source: EPA).Roofing products with the ENERGY STAR logo meet the EPA criteria for reflectivity andreliability. Roof solar reflectance requirements for ENERGY STAR roofing products aresummarized in Table 1.

See the ENERGY STAR Roofing Web site for technical criteria, a list of qualifying prod-ucts and additional information.

Table 1: EPA Energy Star Roof Criteria

Roof Type SlopeInitial SolarReflectance

3-Year SolarReflectance

Low-Slope Roof ≤ 2:12 0.65 0.50

Steep-Slope Roof > 2:12 0.25 0.15


62

IDEASS WE MR EQ

Credit 7Green Building ConcernsAs the built environment grows and re-places natural settings, it also relinquishesassociated ecological services. Vegetationcools the area surrounding it via shade andevapotranspiration. The use of dark, non-reflective surfaces for parking, roofs, walk-ways and other surfaces contributes to heatisland effects created when heat from thesun is absorbed and radiated back to sur-rounding areas. As a result of heat islandeffects, ambient temperatures in urbanareas can be artificially elevated by morethan 10°F when compared with surround-ing suburban and undeveloped areas. Thisresults in increased cooling loads in thesummer, requiring larger HVAC equip-ment and energy for building operations.Heat island effects can be mitigatedthrough the application of shading and theuse of materials that reflect the sun’s heatinstead of absorbing it.

Figure 1 illustrates heat island effects invarious cities throughout the UnitedStates. The greater amount of coolingdegree-days in urban locations means thatair-conditioning systems must workharder and use more energy to maintainthermal comfort in buildings.


Heat island effects are detrimental to sitehabitat, wildlife and migration corridors.Plants and animals are sensitive to highertemperatures and may not thrive in areasthat are unnaturally hot. Reduction ofheat island effect minimizes disturbanceof local microclimates. This can reducesummer cooling loads that in turn reduceenergy use and infrastructure require-ments.

Economic Issues

According to the EPA, about $40 billionis spent annually in the United States toair-condition buildings—one-sixth of allelectricity generated in a year. Reductionin heat islands lowers the cost of coolingand HVAC equipment needs. Energy tocool buildings is a substantial cost over abuilding’s lifetime.

Higher initial costs may result from in-stallation of additional trees and architec-tural shading devices. However, theseitems have an acceptable payback whenintegrated into a whole systems approachthat maximizes energy savings.

Figure 1: Percentage Increase in Cooling Degree Days for Select Cities

0%

Denver

Chicago

Detroit

Seattle

Baltimore

New York

St. Louis

Washington, DC

Los Angeles

20%

Increase in Cooling Degree Days

40% 60% 80% 100%

Credit Synergies










EQ Credit 7Thermal Comfort


63

IDEASS WE MR EQ

Credit 7Design Approach

Strategies

Shade constructed surfaces (e.g. roof,roads and sidewalks) on the site withlandscape features and minimize the over-all building footprint. Consider replac-ing constructed surfaces with vegetatedand/or permeable surfaces such as gardenroofs and open grid paving or specifyhigh-albedo materials to reduce heat ab-sorption.

Technologies: Non-Roof

Paving Materials generally exhibit lowreflectance. Asphalt’s reflectance rangesfrom 0.05 to 0.10 when new and 0.10 to0.15 when weathered. Standard gray-ce-ment concrete reflectance is 0.35 to 0.40when new and 0.20 to 0.30 when weath-ered. White-cement concrete reflectanceis 0.70 to 0.80 when new and 0.40 to 0.60when weathered. Note that the stated re-flectance values are for pavements createdin a laboratory. Concrete made withwhite cement may cost up to twice asmuch as that made with gray cement.Some blended cements (e.g., slag ce-ments) are very light in color and cost thesame as gray cement (Source: “Albedo: AMeasure of Pavement Surface Reflec-tance,” R&T Update #3.05, June 2002,American Concrete Pavement Associa-tion, www.pavement.com/techserv/RT3.05.pdf ). Because pavement is ubiq-uitous, even a small improvement in al-bedo can make an impact. A simulationby Lawrence Berkeley National Labora-tory predicted that increasing thereflectivity of 1250 km of pavement inLos Angeles by 0.25 would result in $15million worth of energy savings and re-duce smog-related medical and lost-workexpenses by $76 million per year.

Coatings and integral colorants can be usedin parking surfaces to improve solar reflec-tance. If reflective coatings, light concreteor gravel cannot be used, consider an open-

grid paving system that increases pervious-ness by at least 50%, which remains coolerbecause of evaporation.

Vegetation can shade buildings and pave-ments from solar radiation and cool theair through evapotranspiration. Provideshade using native or climate-toleranttrees, large shrubs and non-invasive vines.Trellises and other exterior structures cansupport vegetation to shade on parkinglots, walkways and plazas. Deciduoustrees allow buildings to benefit from so-lar heat gain during the winter months.On site locations where tree planting isnot possible, use architectural shadingdevices to block direct sunlight radiance.

Technologies: Roof

To maximize energy savings and minimizeheat island effects, materials must exhibit ahigh solar reflectance and a high thermalemittance over the life of the product. Readthe manufacturer’s data when selecting aproduct based on a material’s reflective prop-erties. Not all manufacturers conduct solarreflectance and thermal emittance testingas a matter of course, although research onurban heat islands has helped to expose theproblem and encourage such testing. Farmore often, manufacturers measure visiblereflectance.

Visible reflectance correlates to solar re-flectance, but the two quantities are notequal because solar gain covers a widerrange of wavelengths than visible light.A material that exhibits a high visible re-flectance usually has a slightly lower solarreflectance. For example, a good whitecoating with a visible reflectance of 0.8typically has a solar reflectance of 0.7.Therefore, it is necessary to measure thesolar reflectance of the material even if thevisible reflectance is known.

Visit the ENERGY STAR® Web site to lookfor compliant roofing products and cross-reference with the emissitance data on theLawrence Berkeley National Laboratory’sCool Roofing Materials Database


64

IDEASS WE MR EQ

Credit 7

(eetd.lbl.gov/CoolRoofs) and the CoolRoof Rating Council Web site(www.coolroofs.org).

Table 2 provides example values to give ageneral idea of initial solar reflectance andinfrared emittance for common roofingmaterials. Typically, white roofing prod-ucts exhibit higher performance charac-teristics than nonwhite products. Perfor-mance varies by roofing material as wellas brand.

The information below is a summary ofrelevant information from the LawrenceBerkeley National Laboratory’s CoolRoofing Materials Database.

Asphalt Roofing exhibits rather low re-flectance. Premium white shingles areonly about 30% reflective, and other col-ors reflect less. Thermal emittance is gen-erally high. Thus, white asphalt roofingmight achieve credit requirements for asteep-slope application.

Coatings contain transparent polymericmaterials and a white pigment to makethem opaque and reflective. White coat-ings typically reflect 65% or more of thesun's energy and protect the polymermaterial and/or substrate underneathfrom UV damage. Coatings are appliedin thicknesses of at least 20 mils (for maxi-mum reflectance), and up to 50 mils (forgreater durability). Reflectivity perfor-mance will benefit from occasional clean-ing. Tinted (colored) coatings cost moreand reflect less sunlight.

Garden Roofs minimize heat island ef-fects and have aesthetic value. Garden

roofs or green roofs are vegetated surfacesthat capture rainwater and return a por-tion of it back to the atmosphere throughevapotranspiration, which cools trees andthe surrounding air. Vegetation experi-ences lower peak temperatures—60 to100 degrees Fahrenheit compared to 190degrees on traditional rooftops—becauseit contains moisture. Garden roofs canpotentially save energy used for heatingand cooling. Some garden roofs requireplant maintenance and are consideredactive gardens, while other garden roofshave grasses and plants that require nomaintenance or watering. All types ofgarden roofs require periodic inspectionbut are expected to have longer lifetimesthan conventional roofs because the un-derlying waterproof membrane is shieldedfrom the effects of ultraviolet radiationand weather.

Membrane Roofing is fabricated fromstrong, flexible, waterproof materials.There are four types of cool roofing mem-branes: EPDM, CSPE, PVC and TPO.These membranes typically exhibit solarreflectance of 0.75. When a dark mem-brane (or other roofing such as modifiedbitumen) is surfaced with roofing gran-ules such as gravel, the roof has the solarreflectance of asphalt shingles, which isquite low.

Metal Roofing is typically steel or alumi-num based, although there is still a smallamount of copper and tin roofing used to-day. Bare and coated metal roofing prod-ucts typically have a solar reflectance of 60%to 80%, and a low thermal emittance.

Table 2: Cool Roofing Materials

Roofing MaterialInitial SolarReflectance

InfraredEmittance

Coating, White 0.75 0.80 – 0.90

Membrane, White 0.75 0.80 – 0.90

Concrete Tile, White

Source: LBNL Cool Roofing Materials Database: eetd.lbl.gov/CoolRoofs

Note: This table shows common or possible values. Values vary per specific brand and product.

0.73 0.80 – 0.90


65

IDEASS WE MR EQ

Credit 7


Site selection and site planning have a sig-nificant effect on urban heat islands.Shading from evergreen trees and archi-tectural shading devices may interferewith possible solar benefits. Deciduoustrees will allow for solar heat gain duringthe winter months. Shading strategiesshould be integrated with solar strategiessuch as daylighting, solar heating andphotovoltaic cells.

Garden roofs reduce stormwater volumesthat may be collected for non-potablepurposes. If water reuse and garden roofstrategies are applied together, it is nec-essary to perform a water balance to de-termine the estimated volumes of wateravailable for reuse. Stormwater runoffvolumes from garden roofs depend on thelocal climate, depth of soil, type of plantsused and other variables. However, allgarden roofs decrease stormwater volumessubstantially.

Light-colored pavements may create glarefrom reflection, posing a hazard to vehicletraffic and annoyance for building occu-pants. Buildings in very cold climates maynot experience year-round energy benefitsfrom reflective roofing and other surfaces,due to the inverse impact that lower heatabsorptivity and higher emittance have onheating energy needs. Increasing the re-flectance of a roof reduces annual cool-ing energy use in almost all climates.

Calculations

The following calculation methodologyis used to support the credit submittalslisted on the first page of this credit.

Shading of Non-Roof Impervious Sur-faces

1. Identify all non-roof impervious sur-faces on the project site and sum the totalarea.

2. Identify all trees that contribute shade tonon-roof impervious surfaces. Calculate theshade coverage provided by these trees afterfive years on the non-roof impervious sur-faces on June 21 at noon solar time to de-termine the maximum shading effect. Addthe total area of shade provided for non-roof impervious surfaces.

3. Shade must be provided for at least30% of non-roof impervious surfaces toearn this point (see Equation 1).

Impervious Surface Calculations

1. Calculate the total parking lot area ofthe project. Parking lots include parkingspaces and driving lanes. Exclude park-ing spaces that do not receive direct sun(e.g., underground parking and stackedparking spaces), sidewalks, roadways andother impervious surfaces that cannotsupport vehicle loads.

2. Calculate the parking area that is de-signed with pervious paving materials.

3. A minimum of 50% of the total park-ing area must be comprised of pavingmaterials that exhibit less than 50% im-perviousness (see Equation 2).

Equation 3:

Equation 2:

Equation 1:

]SF[AreaperviousImTotal

]SF[AreaperviousImShaded[%]Shade =

]SF[AreaParkingTotal

]SF[AreaParkingPervious[%]Pervious

Portion=

]SF[AreaRoofTotal

]SF[AreaRoofVegetated[%]

VegetatedRoof

=


66

IDEASS WE MR EQ

Credit 7

Vegetated Roof Calculations

1. Calculate the total roof area of theproject. Deduct areas with equipmentand other appurtenances.

2. Calculate the area of roof that is sur-faced with a vegetated roof system.

3. Calculate the percentage of the totalroof area that is covered with a green veg-etated roof system (see Equation 3).

Resources

Web Sites

American Concrete Pavement Association

www.pavement.com, 847-966-2272

See R&T Update #3.05, June 2002, “Al-bedo: A Measure of Pavement Surface Re-flectance,” www.pavement.com/techserv/RT3.05.pdf, for reflectance data and re-lated information.

Cool Roof Rating Council

www.coolroofs.org, (866) 465-2523

Created in 1998 to develop accurate andcredible methods for evaluating and la-beling the solar reflectance and thermalemittance (radiative properties) of roof-ing products and to disseminate the in-formation to all interested parties.

ENERGY STAR® Roofing Products

www.energystar.gov, (888) 782-7937

Provides solar reflectance levels required tomeet U.S. EPA ENERGY STAR labeling re-quirements, a list of compliant products (bymanufacturer) for low-slope and steep-sloperoofs, and additional information.

Greenroofs.com

www.greenroofs.com

An independent clearinghouse for infor-mation about vegetated roofs.

Lawrence Berkeley National Labora-tory Heat Island Group

eetd.lbl.gov/HeatIsland/graphic, 510-486-7437

Presents research on the effects of heatislands and provides specific informationand data on roofing materials. For reflec-tance and emissivity data, see eetd.lbl.gov/CoolRoofs.

Sacramento Cool Community Program

www.energy.ca.gov/coolcommunity/strat-egy/coolpave.html

A program of the Sacramento Tree Foun-dation that promotes the use of vegeta-tion strategies, cool roofing and cool pave-ments to reduce the city’s heat island.Sacramento’s parking lot shading ordi-nance is provided, as well as other re-sources helpful for local governments.

Definitions

Albedo is synonymous with solar reflec-tance (see below).

Heat Island Effects occur when warmertemperatures are experienced in urbanlandscapes compared to adjacent ruralareas as a result of solar energy retentionon constructed surfaces. Principal sur-faces that contribute to the heat islandeffect include streets, sidewalks, parkinglots and buildings.

Infrared or Thermal Emittance is a pa-rameter between 0 and 1 (or 0% and100%) that indicates the ability of a ma-terial to shed infrared radiation (heat).The wavelength range for this radiantenergy is roughly 3 to 40 micrometers.Most building materials (including glass)are opaque in this part of the spectrum,and have an emittance of roughly 0.9.Materials such as clean, bare metals arethe most important exceptions to the 0.9rule. Thus clean, untarnished galvanizedsteel has low emittance, and aluminumroof coatings have intermediate emittancelevels.


67

IDEASS WE MR EQ

Credit 7

Open-Grid Pavement is defined forLEED purposes as pavement that is lessthan 50% impervious.

Solar Reflectance (albedo) is the ratioof the reflected solar energy to the incom-ing solar energy over wavelengths of ap-proximately 0.3 to 2.5 micrometers. A re-flectance of 100% means that all of theenergy striking a reflecting surface is re-flected back into the atmosphere and noneof the energy is absorbed by the surface.The best standard technique for its de-termination uses spectro-photometricmeasurements with an integrating sphereto determine the reflectance at each dif-ferent wavelength. An averaging processusing a standard solar spectrum then de-termines the average reflectance (seeASTM Standard E903).

Underground Parking is a “tuck-under”or stacked parking structure that reducesthe exposed parking surface area.


68

IDEASS WE MR EQ

Credit 7


69

IDEASS WE MR EQ

Credit 8Light Pollution Reduction

Intent

Eliminate light trespass from the building and site, improve night sky access and re-duce development impact on nocturnal environments.

Requirements

Meet or provide lower light levels and uniformity ratios than those recommended bythe Illuminating Engineering Society of North America (IESNA) Recommended Prac-tice Manual: Lighting for Exterior Environments (RP-33-99). Design exterior lightingsuch that all exterior luminaires with more than 1000 initial lamp lumens are shieldedand all luminaires with more than 3500 initial lamp lumens meet the Full CutoffIESNA Classification. The maximum candela value of all interior lighting shall fallwithin the building (not out through windows) and the maximum candela value of allexterior lighting shall fall within the property. Any luminaire within a distance of 2.5times its mounting height from the property boundary shall have shielding such thatno light from that luminaire crosses the property boundary.

Submittals

❏ Provide the LEED Letter Template, signed by a lighting designer or an appropri-ate party, declaring that the credit requirements have been met.


IESNA Recommended Practice Manual: Lighting for Exterior Environments(IESNA RP-33-99)

Illuminating Engineering Society of North America, www.iesna.org, (212) 248-5000

This standard provides general exterior lighting design guidance and acts as a link toother IESNA outdoor lighting Recommended Practices (RPs). IESNA RP documentsaddress the lighting of different types of environments. RP-33 was developed to aug-ment other RPs with subjects not otherwise covered and is especially helpful in theestablishment of community lighting themes and in defining appropriate light trespasslimitations based on environmental area classifications. RP-33 addresses visual issuessuch as glare, luminance, visual acuity and illuminance. Also covered are exteriorlighting design issues including community-responsive design, lighting ordinances,luminaire classification, structure lighting, and hardscape and softscape lighting. Lightlevel recommendations in RP-33 are lower than in many other RPs, since RP-33 waswritten to address environmentally sensitive lighting.

Another useful Recommended Practice is RP-20-98, “Lighting for Parking Facili-ties.” RP-20 discusses lighting design issues and makes light level recommendationsfor open and covered parking facilities. Not all the light level recommendations inthe RP-20, or in any of the RPs, are appropriate for lighting in environmentallysensitive areas, so it is important to try to use the lowest recommended values. It isalso important to recognize that, as a whole, different IESNA RP documents are notin agreement on all lighting issues and many of the RPs will be revised to include

1 point


70

IDEASS WE MR EQ

Credit 8

Table 1: Light Trespass Limitations

Environmental Zone Description

E1: Intrinsically Dark Parks and residential areas where controlling light pollution is a high priority

0.1

0.1 E2: Low Ambient Brightness Outer urban and rural residential areas

E3: Medium Ambient Brightness Urban residential areas 0.2

0.6 E4: High Ambient Brightness Urban areas having both residential and commercial use and experiencing high levels of nighttime activity

Note: Table 1 has been adapted from IESNA RP-33-99. “Post Curfew” recommendations have been used for all values to

ensure that light trespass is minimized for each environmental zone. It is recognized that in situations where the property line

is very close to the area of development (commonly referred to as “zero property line”), and where lighting is required for

emergency egress purposes, it may not be possible to meet the Table 1 recommendations. These situations should be

carefully explained and documented.

Recommended Maximum

Illuminance Levels [fc]

recommendations based on environmental zones. The designer must interpretrelated documents to find a recommendation that uses the lowest light levels whilestill addressing specific project issues. Table 1 provides suggested light trespasslimitations based on different types of environmental zones. Illuminance values aremeasured at the eye on a plane perpendicular to the line-of-sight.


71

IDEASS WE MR EQ

Credit 8

ing community. Another key benefit isbetter visual comfort and improved visibil-ity. Sensitively designed lighting systems thatminimize glare and provide more uniformlight at lower levels will help create aestheti-cally pleasing environments that are saferand more secure. A carefully designed andmaintained outdoor lighting system canhelp a project be a non-intrusive memberof the community.

Design Approach

Strategies

Eliminate all unshielded fixtures (flood-lights) on the project site. Interpret be-tween existing standards and design forthe lowest possible light levels while ad-dressing safety, security, access, way find-ing, identification and aesthetics. UseIESNA designation “full cutoff” lumi-naires for lamp packages with more than3500 initial lumens and provide shield-ing for luminaires with lamps havingmore than 1000 initial lumens. Theshielding of low brightness luminaires canvary depending on the ambient bright-ness of the surrounding environment andon the type of environmental zone (as de-scribed in IESNA RP-33-99) that bestdescribes the project. For example, in siteswhere there is low ambient brightness andthere is a great potential for glare and lighttrespass, even sources with very low lu-men output may need to be fully shieldedto maintain the highest levels of visualcomfort. In these situations, a luminairewith IESNA full cutoff designation mightbe appropriate. In high ambient bright-ness areas where less shielding is required,a luminaire with IESNA semi-cutoff ornon-cutoff designations may be appropri-ate. The designer should take care in mak-ing the decision on how much shieldingis required.

Minimize or eliminate lighting of archi-tectural and landscape features. Wherelighting is required for safety, security,

Green Building ConcernsOutdoor lighting is necessary for illumi-nating connections between buildingsand support facilities such as sidewalks,parking lots, roadways and communitygathering places. However, light trespassfrom poorly designed outdoor lightingsystems can affect the nocturnal ecosys-tem on the site, and light pollution lim-its night sky access. Through thoughtfuldesign and careful maintenance, outdoorlighting can address night sky visibilityissues and site illumination requirements,while minimizing the negative impact onthe environment.

Environmental Benefits

Sensitively designed outdoor lighting canextend access and use of many areas intothe nighttime hours. We can gain aunique appreciation for a place at nightbecause of sensitively and creatively de-signed lighting systems. But any timelighting is added to an exterior environ-ment, light pollution and the potentialfor light trespass increase. Even with thebest full cutoff luminaires and the lowestwattage lamp packages, the added lightwill be reflected off surfaces and into theatmosphere. Using the minimum amountof lighting equipment, limiting or elimi-nating all landscape lighting, and avoid-ing light pollution and trespass throughthe careful selection of lighting equip-ment and controls allow nocturnal life tothrive while still providing for nighttimeactivity.

Economic Benefits

Carefully designed exterior lighting solu-tions can reduce infrastructure costs andenergy use when compared to commonpractice solutions. Energy and mainte-nance savings over the lifetime of theproject can be substantial.

Community Benefits

Minimizing light pollution and trespass al-lows for night sky access by the surround-

Credit Synergies





EA Prerequisite 1Fundamental BuildingSystems Commissioning


EA Credit 3AdditionalCommissioning

EA Credit 5Measurement &Verification


72

IDEASS WE MR EQ

Credit 8

4. Use the least amount of lighting equip-ment possible to achieve the goals of theproject, but balance the quantity of equip-ment used with the need to provide forglare control and uniform lighting. Inmost cases, it is better to have two lumi-naires with lower light output and goodglare control than one higher outputluminaire.

5. Select all lighting equipment carefully.Any type of luminaire, whether it is fullcutoff, semi-cutoff or non-cutoff, can pro-duce excessive brightness in the form ofglare. For example, horizontal lamp posi-tions in full cutoff luminaires tend to pro-duce much less glare than vertical lamps.Selecting high-performance equipment ofgood quality is not only essential in main-taining visual quality, but also will quicklypay for itself in reduced maintenancecosts.

6. Design exterior lighting to produceminimal upward illumination from director reflected light sources. Select luminairelocations carefully to control glare andcontain light within the design area. Payspecial attention to luminaires that arelocated near the property line to ensurethat no measurable light from these lu-minaires crosses the project boundary.

7. Use the minimum amount of lightnecessary and only light areas that requireit. Design and develop a control schemeto minimize or turn lighting off afterhours or during post-curfew periods.

8. Create a computer model of the pro-posed electric lighting design and simu-late system performance. Use this tool toprovide point by point horizontal illumi-nance information or an isofootcandlecontour map demonstrating that illumi-nance values are zero (or near zero) at theproject boundary. Where luminaires arewithin 2.5 times their mounting heightfrom the project boundary and the lightlevels are not zero at the boundary, lighttrespass is more likely to be a problem. In

egress or identification, utilizedownlighting techniques rather thanuplighting. For example, in environmentsthat are intrinsically dark, no landscapefeatures should be lighted, and architec-tural lighting should be designed only asa last resort when other strategies havefailed to provide the minimum amountof required lighting. In areas of high am-bient brightness, some low level (subtle)lighting of features, facades or landscapeareas may be appropriate in pedestrian en-vironments or for identification and wayfinding in other areas where light trespassis not likely to be an issue. However, evenin areas of high ambient brightness, allnon-essential lighting, including land-scape and architectural lighting, shouldbe minimized or turned off after hours.If shielded, low brightness sources are usedto selectively light features, they shouldbe properly aimed so that light from theluminaires cannot be measured acrossproject boundaries. In all cases, controlsshould be used wherever possible to turnoff lighting after normal operating hoursor in post-curfew periods. Consider atleast the following strategies when design-ing the exterior lighted environment:

1. Employ a lighting professional to as-sess the project’s lighting needs and pro-vide recommendations based specificallyon lighting for a sustainable design envi-ronment.

2. Carefully review and respond to anylocal or regional lighting ordinances orbylaws that might impact the lightingdesign for the project site.

3. Consult IESNA RP-33 and determinethe type of environmental zone that theproject falls under from Intrinsically Dark(Zone E1) to High Ambient Brightness(Zone E4). Understand the design impli-cations of the environmental zone thatbest fits the project and study neighbor-ing areas to identify potential light tres-pass problems.


73

IDEASS WE MR EQ

Credit 8

this case a simple calculation can be per-formed to show that the “line of sight”illuminance limits for light trespass listedin Table 1 have been met. A procedurefor evaluating light trespass is outlined inthe calculations section.

9. After the lighting system is constructed,it should be commissioned to ensure thatit is installed and operating properly.Maintenance should be performed on thesystem on a regular basis to ensure that itcontinues to operate correctly, and thatlight pollution and trespass are mini-mized.

Technologies

Design site lighting and select lightingequipment and technologies to have mini-mal impact off-site and minimal contri-bution to sky glow (light pollution).Employ luminaires with the proper op-tics and shielding. Use low-reflectanceground covers and minimize the use ofhighly reflective and specular surfaces thatmay be a source of reflected glare. Whensurfaces are used to reflect light, use lowerwattage light sources to reduce light lev-els and overall brightness. Even lowbrightness luminaires should be aimedcarefully to eliminate glare and light tres-pass. Aiming angles greater than 45 de-grees above vertical should be avoided.Luminaires with lockable aiming shouldbe used in instances where glare controlis very important or where special aimingmust be maintained. Use motion sensors,photocells, stepped dimming, automaticswitching and time clocks to control ex-terior lighting during pre- and post-cur-few periods. Exterior signs that must belighted should be made as small as pos-sible and internally lighted signs shouldhave letters and images on a dark back-ground. Externally lighted signs shouldbe downlighted from the top wheneverpossible, and the luminaires used shouldbe full cutoff with additional shielding asnecessary to control stray light that doesnot illuminate the sign.


Exterior lighting strategies are affected bythe transportation program, as well by asthe total area of developed space on theproject site. In addition to energy effi-ciency, the exterior lighting system re-quires commissioning and measurement& verification. ASHRAE 90.1–1999 (seeEA Credit 1) includes provisions for ex-terior facade lighting and addresses auto-matic lighting controls, control devices,minimum lamp efficacy and lightingpower limits. The standard requires sepa-rate calculations for interior and exteriorlighting loads and, thus, trade-offs be-tween interior and exterior loads are notpermitted. See the standard for more in-formation.

Education is one of the most importantaspects of sustainable lighting design.Some people believe incorrectly that lowerlevels of outdoor lighting will create safetyor security problems. However, it can beeasily demonstrated that the quality of thelighting design has a much greater impacton safety and the perception of securitythan does light level. Low light level en-vironments with good uniformity of lightand controlled glare are often environ-ments that provide good visibility. Envi-ronments with good visibility are usuallysafer and more secure. These environ-ments also use less energy, and they causeless light pollution and trespass. It is notonly acceptable, but also sometimes pre-ferred not to light an environment.

Calculations

The following materials are recom-mended to support the credit:

1. Provide an exterior site plan showing:

● All buildings, parking and pedes-trian areas, trees and landscapefeatures

● A luminaire schedule showingthe type, style, location, height,orientation, shielding and aim-


74

IDEASS WE MR EQ

Figure 1: Example of a Site Lighting Plan

Credit 8

Courtesy of Clanton & Associates


75

IDEASS WE MR EQing of all light sources and alllighting control devices

● A computer-generated lightingcalculation indicating horizontalilluminance on a 10’x10’ mini-mum grid and a minimum of 10feet beyond the lot or propertyboundary for areas that are rep-resentative of each design condi-tion (Isofootcandle contours arealso acceptable for showing lightlevels). Include maximum tominimum uniformities for eachspecific type or area of use, andany associated light loss factors(LLF) used in the procedure.RP-33 references appropriateRPs for various design condi-tions. Consult these RPs for rec-ommended criteria.

2. Provide a calculation for “line of sightilluminance” (light trespass) for lumi-naires near the property line where thecalculated light levels did not reach zero.See Table 1 for light trespass limits. Tocalculate line of site illuminance (E

line):

multiply the horizontal illuminance (Ehorz

)(at ground level for LEED calculationpurposes) on the property line by one overthe sine of the angle (1/sinθ), where theangle is between the ground plane at thepoint of measurement and a line drawnfrom that point to the light source.

3. Catalog cut sheets for all exterior lu-minaires with more that 3500 lumenlamps, demonstrating that they meet theFull Cutoff IESNA Classification, andindicating lamp type, distribution typeand any additional shielding.

4. Catalog cut sheets for all exterior lu-minaires with more than 1000 lumenlamps, demonstrating that they are appro-priately shielded for the project’s Environ-mental Zone.

5. Provide interior lighting design draw-ings for the building’s perimeter areasdemonstrating that the maximum candela

value of interior lighting falls within thebuilding and not out through the win-dows.

The site lighting plan illustrated in Figure1 includes a parking lot and office buildingin an area of low ambient brightness (Envi-ronmental Zone 2). The luminaire sched-ule describes the light source used in eachluminaire and the shielding classificationprovided to meet the credit requirements.Note that a summary is used in this examplefor illustration purposes. A complete sched-ule is required.

The site lighting plan indicates major sitefeatures, luminaire layout and calculatedpoint-by-point illuminance values atground level on a grid that is less than10’x10’, or indicated by isofootcandlelines. The maximum to minimum uni-formity ratio is 7:1, which meets the cri-teria in IESNA RP-20, which RP-33 ref-erences for parking facilities.

The lighting point-by-point calculationplan shows that the illuminance value atthe property line does not reach 0 at PointA (E

horz at Point A is 0.01fc). Therefore,

the “line of site illuminance” must be cal-culated for the adjacent luminaire. Thecalculation E

line=(1/sin33°)(0.01fc) yields

a result of 0.018fc. Since this value is lessthan the 0.1fc limitation given by IESNARP-33-99, the LEED requirement hasbeen met for Point A.

The angle of the maximum candela valuefor interior luminaires is determined fromthe luminaire photometry. It is then dia-gramed on the building section. The siteand building sections in Figure 2 illus-trates that the maximum candela valuesfor luminaire types “X” and “Y” fall withinthe building.

Credit 8


76

IDEASS WE MR EQ

Credit 8

Resources

Web Sites

Illuminating Engineering Society ofNorth America

www.iesna.org, (212) 248-5000

The most comprehensive source for light-ing information.

International Dark Sky Association

www.darksky.org, (520) 293-3198

A nonprofit organization dedicated toproviding education and solutions forlight pollution and light trespass.

Lighting Research Center

www.lrc.rpi.edu

A leading university-based research centerdevoted to providing objective informationabout lighting technologies, applicationsand products to aid facility managers, utili-ties, lighting designers, engineers and elec-trical contractors. The Web site includesthe National Lighting Product InformationProgram (NLPIP), which provides free pub-

lications about lighting topics (such as lightpollution) and products.

New England Light Pollution AdvisoryGroup (NELPAG)

cfa-www.harvard.edu/cfa/ps/nelpag.html

A volunteer group that educates profes-sionals and the public on the virtues ofefficient, appropriately sited glare-freeoutdoor night lighting by addressingsafety, right to privacy, light trespass, nightsky vision and energy issues.

Print Media

Outdoor Lighting Manual for VermontMunicipalities, PTI Publications Center,(301) 490-2188, Order No. DG/95-308.

Definitions

Curfew Hours are locally determinedtimes when greater lighting restrictionsare imposed.

Cutoff Angle is the angle between thevertical axis of a luminaire and the firstline of sight (of a luminaire) at which thelight source is no longer visible.

Figure 2: Building and Site Sections

Courtesy of Clanton & Associates


77

IDEASS WE MR EQ

Credit 8

Illuminance is the amount of light fall-ing on a surface, measured in units of foot-candles (fc) or lux (lx).

A Footcandle (fc) is a measure of lightfalling on a given surface. One footcandleis equal to the quantity of light falling ona one-square-foot area from a one can-dela light source at a distance of one foot.Footcandles can be measured both hori-zontally and vertically by a footcandle or“light meter.”

A Full Cutoff luminaire has zero candelaintensity at an angle of 90 degrees abovethe vertical axis (nadir) and at all anglesgreater than 90 degrees from nadir. Ad-ditionally, the candela per 1000 lamp lu-mens does not numerically exceed 100(10 %) at an angle of 80 degrees abovenadir. This applies to all lateral anglesaround the luminaire.

Glare is the sensation produced by lumi-nance within the visual field that is sig-nificantly greater than the luminance towhich the eyes are adapted, which causesannoyance, discomfort or loss in visualperformance and visibility

Light Pollution is caused by stray lightfrom unshielded light sources and lightreflecting off surfaces that enters the at-mosphere where it illuminates and reflectsoff dust, debris and water vapor to causean effect know as “sky glow.” Light pol-lution can substantially limit visual accessto the night sky, compromise astronomi-cal research, and adversely affect noctur-nal environments. Stray light that entersthe atmosphere does not increase night-time safety or security and needlessly con-sumes energy and natural resources.

Light Trespass is commonly thought ofas “the light shining in my window.” It isdefined as obtrusive light that is un-wanted, because of quantitative, direc-tional or spectral attributes. Light trespasscauses annoyance, discomfort, distractionor a loss of visibility

Luminance is what we commonly callbrightness or the light coming from a sur-face or light source. Luminance is com-posed of the intensity of light striking anobject or surface and the amount of thatlight reflected back toward the eye. Lu-minance is measured in footlamberts (fl)or candela per square meter (cd/m2).

Shielding is a non-technical term that de-scribes devices or techniques that are usedas part of a luminaire or lamp to limitglare, light trespass and light pollution.


78

IDEASS WE MR EQ

Courtesy of The Aspen Skiing Company

OwnerThe Aspen Skiing Company

Case Study

The Aspen Skiing Company Sundeck RestaurantAspen, Colorado

The Aspen Skiing Company Sundeck Restaurant is a LEED™Version 1.0 Bronze Pilot Project located atop Aspen Mountain.Interior and exterior lighting plans were designed to minimizeimpacts on the surrounding natural areas. Blackout curtains wereinstalled for interior service areas where unshielded fixtures arelocated to block light from spilling out of windows. Lightingfixtures were chosen carefully to eliminate direct glare from lightsources and indirect glare from expected viewing angles. Reflec-tance of interior surfaces that can be viewed from off-site is lim-ited to 40%. Exterior lighting is limited to code requirementsand outdoor fixtures are baffled to reduce light trespass. All exte-rior lighting is automatically shut off at 11 pm. Reflective sur-faces on the project site were minimized and snow is removedfrom below windows to reduce the potential for light reflection.

Credit 8

leed ncv2.1 ss

Documents

site selectionss credit

stormwatermanagementss

urban redevelopmentss

local erosion

site alternatives

reduceheat islandsss

site selection process

erosion control plan