residential building energy standards (rbes) and commercial building energy standards (cbes) updates...

Residential Building Energy Standards (RBES)

and Commercial Building

Energy Standards (CBES) Updates

Better Buildings by Design Conference - February 10,

2011Navigant Consulting, Inc. (Consultants to Vermont

DPS)

Efficiency Vermont is a Registered Provider with The American Institute of Architects Continuing Education Systems (AIA/CES). Credit(s) earned on completion of this program will be reported to AIA/CES for AIA members. Certificates of Completion for both AIA members and non-AIA members are available upon request.

This program is registered with AIA/CES for continuing professional education. As such, it does not include content that may be deemed or construed to be an approval or endorsement by the AIA of any material of construction or any method or manner of handling, using, distributing, or dealing in any material or product.

Questions related to specific materials, methods, and services will be addressed at the conclusion of this presentation.

Learning Objectives

At the end of this program, participants will be able to:

Gain a better understanding of the current VT residential and commercial energy codes

Understand challenges and issues related to implementation and enforcement of the energy code

Understand the overall process involved in current and future Vermont energy code updates

Course EvaluationsIn order to maintain high-quality learning experiences,

please access the evaluation for this course by logging into CES Discovery and clicking on the Course

Evaluation link on the left side of the page.

5

Agenda

• Background and legislative history—Stu Slote

• Residential Building Energy Standards (RBES)—Lee Wood

• Q & A

• Commercial Building Energy Standards (CBES)—Tim Guiterman

• Q & A

6

Code Update Process•Last Update: 2003 VT RBES

•ARRA Requirements: 2009 IECC

•May 27, 2009 - legislature adopted Act 45

•Stakeholder meetings held to gather feedback

•Advisory Committee meetings

•DPS filed rule with ICAR (Interagency Committee on Administrative Rules)

•DPS held public hearing

•LCAR to conduct hearing and vote on rule

•Rule to be adopted 15 days after filed

•RBES handbook update

RBES Update Process

7

CBES Update Process

• Last Update: 2005 VT CBES

• ARRA Requirements: 2009 IECC or ASHRAE 90.1-2007

• Technical Advisory Panel (TAP)—Meetings in June and July of 2010—Highlighted areas for improvement—Included changes from current 2012 IECC /

ASHRAE 90.1-2010 update processes

8

CBES Update Process

Overall direction for CBES Update• Meet minimum 2009 IECC / ASHRAE 90.1-2007

• Add VT-specific amendments and improvements

• Consider substantial changes to create 2012 IECC / ASHRAE 90.1-2010

• New VT CBES codebook (VT-specific version of IECC)

• Continue to maintain reference to ASHRAE 90.1 standard and allow that as approved compliance path

• Public hearing on proposed rule held Jan 27

• Public comment period ended February 4

• LCAR to conduct hearing and vote on rule

• Rule to be adopted 15 days after filed

9

CBES Update Process

Where are Commercial Codes Headed?

Source: NEEP Building Energy Codes Policy 3/1/2009

RESIDENTIAL BUILDING ENERGY STANDARDS

(RBES)

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1 Section 1: RBES Administration

2 Section 2: Major Changes to RBES

Table of Contents

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Administration and Enforcement 2003 2011

Self certification X X

Certificate of compliance X X

Filing process to remain unchanged

Section 1 » RBES Administration

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Applicability 2003 2011

New single family homes X X

New multifamily homes X X

Change in occupancy or use X X

Change in space conditioning X

Additions, alterations, renovations, or repairs

X


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Additions, alterations, renovations, or repairs

Conform as with new construction

Unaltered portions do not need to comply

Additions can comply alone or in combination with existing building


Exceptions

Storm windows over existing fenestration

Glass only replacements

Exposed cavities already filled with insulation

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Exemptions 2003 2011

Very low energy use buildings X X

Unconditioned buildings X X

Existing Buildings X X

Historic Buildings X X

Owner Built Homes X X

Hunting Camps X X


RBES

Compliance Paths

Prescriptive Approach

Mandatory Requirements

Start

Performance Approach

Either

R-Values Table

402.1.1

U-Factor Alternative

Table 402.1.3

Total UA Alternative

402.1.4

REScheck

HERS Rating


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1 Section 1: RBES Administration

2 Section 2: Major Changes to RBES

Table of Contents

18

Mandatory Requirements 2003 2011

Piping insulation X XVapor Retarder X XMechanical ventilation X XCombustion safety X XAir Sealing and verification XLighting XFenestration U-factors XProgrammable thermostat XDuct sealing and testing XEquipment sizing XSnow melt system controls XPools, hot tubs and spas X

Section 2 » Major Changes to RBES

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Building Envelope

ComponentR-Value Exemptions

2003 2011 1. R-38 if uncompressed

2. 500 ft2 for vaulted ceilings

Ceiling 38 49

Source: US DOE


20

Building Envelope

ComponentR-Value Notes

2003 2011 R-20 cavityorR-13 cavity + R-5

sheathing

Wood Frame Wall 13 20 or

13 + 5

Source: DOE


21

Building Envelope


2003 2011 R-15 continuousorR-20 cavity

Basement or Crawlspace

Wall13 15 / 20

Source: Building Science Corp


22

Building Envelope


2003 2011 Heated slabs must have R-15 beneath entire slabSlab Edge 10, 4ft 15, 4ft

Source: Building Energy Codes Program


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Component Window U-Factor Skylight U-Factor

2003 2011 2003 2011

Fenestration 0.40 0.32 NR 0.55

Fenestration

Notes1. Area-weighted averages2. 15 ft2 of glazing exempt3. One opaque door exempt


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Component RBES 2003 RBES 2011

Air Leakage No testing requirements

1.Test: < 5 ACH@50 2.Visual Inspection

Checklist

Air Leakage

Source: RBES Handbook


25


Spillage Testing

No testing requirements

Must establish draft without spillage within two minutes

Spillage Testing

Source: Saturn Resource Management


26


Programmable Thermostat No requirement MANDATORY

Temperature Controls


Lighting No requirement50% of lamps in permanent fixtures high-efficacy

Lighting


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COMPONENT RBES 2003 RBES 2011

Duct Sealing No verification requirement

Must be verified by:*1. Post-construction test:

Leakage to outdoors < 6 cfm per 100 ft2 of conditioned floor area (CFA)

2. Rough-in test: Total leakage < 3 cfm per 100 ft2 of conditioned floor area (CFA)

Duct Insulation

R-8 Same R-value as surrounding surfaces*

Ducts

* Unless located within conditioned space


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Mechanical Ventilation

COMPONENT 2003 2011

Balanced systems X X

Exhaust-only systems X X

Supply-only systems X


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Piping Insulation Varied R-3

Domestic Hot Water

Source: Saturn Resource Management


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Snow Melt Systems

No requirements Mandatory automatic controls

Pool HeatersMandatory on / off switch

Mandatory on / off switch

Pool Covers (heated pools)

Pool cover requiredPool cover requiredR-12 minimum for hot tubs and spas

Other Requirements


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Component 2003 2011

Basement Wall U-Factor 0.10 0.05

Floor U-Factor 0.033 0.026

Ceiling U-Factor 0.026 0.020

Fenestration U-Factor 0.40 0.30

Log Homes

Log walls must comply with ICC400 with average minimum wall thickness of 5” or greater, and have heating system AFUE of 90% (gas) or 85% (oil). Boilers must have outdoor temperature reset or thermal purge control.


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Questions?

COMMERCIAL BUILDING ENERGY STANDARDS

(CBES)

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CBES Presentation » Overview

• Key Items

• Details on code update—Administration—Definitions—General Requirements—Envelope—Mechanical Systems—Service Water Heating—Electrical Power and Lighting

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CBES Presentation » Key Items

• 2012 IECC and ASHRAE 90.1-2010 recently finalized in Fall 2010

• Significant changes to 2012 IECC initiated by joint proposals—Department of Energy (DOE)—New Buildings Institute (NBI)—American Institute of Architects (AIA)

• Presentation Format

CHAPTER 1ADMINISTRATION

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Introduction to Compliance Process

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Must the Project Comply with the

IECC?

Comply with the Envelope

Requirements

Comply with the Mechanical/SWH

Requirements

Comply with the Power & Lighting

Requirements

Section 502 90.1 Section 5Sections 503 and

50490.1 Section 6 Section 505 90.1 Section 9

Document Compliance with

the IECC

Plan Review

Inspection

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Chapter 1 » Administration

101.2 Scope—Code does not apply to farm structures or

process applications (equipment / systems)

101.5 ComplianceExempt Buildings1.Low energy buildings (<3.4 Btu/h*ft2 for space

conditioning)2.Unconditioned buildings3.Inflatable buildings

Context: Re-organizes exemptions from 2005 CBES. Inflatable & Unconditioned buildings added.

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101.4.3 : Alterations, Additions, Renovations and Repairs—If energy use is not increased, following

need not comply Re-roofing where neither sheathing nor insulation is exposed

Alterations that replace < 50% of luminaires

Alterations that replace only bulb and ballast

Context: New in 2009 IECC


40

103: Construction Documents1. Added: Additional information required on construction

documentsa. Design ambient temperatures; interior temps. for heating

/ cooling modes; relative humidity setpoints; ventilation rates

2. Added: Additional info. required on mechanical equipment schedules

a. Equipment efficiencies; Fan and pump nameplate motor / brake horsepower; Hydronic system (if applicable) supply / return water design temps. for boilers and all terminal devices (e.g. baseboards, unit ventilators, etc); Steam system (if applicable) design pressure for boilers and all terminal devices

Context: Rarely included, but useful information for code review, commissioning, future energy audits, etc.


CHAPTER 2DEFINITIONS

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42

Chapter 2 » Definitions

Context: Definitions complement new/revised sections of code. Many are new in 2009 IECC and some from 2012 IECC.

CHAPTER 3GENERAL

REQUIREMENTS

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Chapter 3 » General Requirements

301: Design Conditions— 2005 CBES: broad allowance for adjustments

— 2011 CBES: adjustments for1. Winter heating design temperatures for projects

located at either:a. Elevation of 1,500 feet or higherb. Caledonia, Essex or Orleans counties

2. As approved by code official or other authority having jurisdiction

Context: Improve language from 2005 VT CBES which allowed adjustments for “local design conditions”

SECTION 502BUILDING ENVELOPE

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Building Envelope

502.2.1: Roof Assembly—Added: Requirement to insulate skylight

and mechanical curbs to at least R-5

Context: Skylight curbs included in proposal for 2012 IECC. Mechanical curb recommended by TAP.

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Table 502.2 (1) Envelope Tables1. Envelope R-Values/U-Factors only for Vermont

Climate Zone (CZ) 6

2. Added additional metal building description and U-factor reference tables

3. Maximum Vertical fenestration area is 40% of above-grade wall area, same as 2009 IECC. 2005 CBES was 50% maximum

Thermal Blocks

Insulation Draped Over Purlin

Insulation Parallel to Purlin

Picture from NAIMAThermal Blocks

Insulation Draped Over Purlin

Insulation Parallel to Purlin

Picture from NAIMA

Building Envelope

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Building Envelope - Opaque Assemblies

Roofs 2005 CBES

2009 IECC /

90.1-2007

2011 CBES

Roof: Insulation entirely above deck

R - 24 ci

U - 0.040

R - 20 ci

U - 0.048

R - 30 ci

U - 0.032

Metal Buildings

R - 19 + R - 10 or R - 30

U - 0.051

R - 13 + R - 19

U - 0.049

R - 11 + R - 13ci

U - 0.045

Steel Joist

R - 30 + R - 5ci (with R - 5 thermal

blocks)U - 0.027

N / A N / A

Attic and other

R - 38U - 0.27

R - 38U - 0.27

R - 38U - 0.027

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Walls-Above Grade

2005 CBES

2009 IECC /

90.1-2007

2011 CBES

Mass

R - 9.5 ci

U - 0.104

R - 13.3 ci

U - 0.080

R - 13.3 ci

U - 0.080

Metal building

R - 19 or R - 6 + R - 13

U - 0.070

R - 13 + R - 5.6 ci

U - 0.069

R - 11 + R - 6.5 ci

U - 0.054

Metal-framed

R - 13 + R - 7.5 ci

U - 0.064

R - 13 + R - 7.5 ci

U - 0.064

R - 13 + R - 7.5 ci

U - 0.064

Wood-framed

and other

R - 19 or R - 12 ci or R - 13 + R -

3.8 ci

U - 0.064

R - 13 + R - 7.5 ci

U - 0.051

R - 13 + R - 7.5 ci or

R - 20 + R - 3.8 ci or

R - 23U - 0.051


Note: VT was already ahead of 2009 IECC. Recommendation to maintain current 2005 VT CBES values.

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Walls-Below Grade

2005 CBES

2009 IECC /

90.1-2007

2011 CBES

Below Grade Wall

R - 10 ci

C - 0.092

R - 7.5 ci

C - 0.119

R - 10 ci

C - 0.092


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Floors 2005 CBES

2009 IECC /

90.1-2007

2011 CBES

Mass

R - 10ci

U - 0.074

R - 12.5 ci

U - 0.064

R - 12.5 ci

U - 0.064

Joist / Framing-Metal*

R - 30

U - 0.038 R - 30

U - 0.033

R - 30

U - 0.033

Joist / Framing-Wood and

Other*

R - 30

U - 0.033

R - 30

U - 0.033

*Note: Final version will consolidate 2 categories into one, per 2009 IECC


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Slab-on-Grade Floors*

2005 CBES

2009 IECC/90.1-2007

2011 CBES

Unheated

R - 10 for 48 inches

F - 0.64

R - 10 for 24 inches below

F - 0.55

R - 10 for 48 inches

F - 0.48**

Heated

R - 10 for entire slab (under slab

and perimeter)

F - 0.55

R - 15 for 24 inches below

F - 0.86

R - 10 for entire slab (under slab and perimeter)

F - 0.55* Insulation shall be placed on the exterior of the foundation

** Change to F-Value from 2005 CBES to reflect vertical installation (Or downward to bottom of slab and then horizontally for total distance shown in table)


53

Opaque Doors

2005 CBES

2009 IECC/90.1-2007

2011 CBES

Swinging U - 0.50 U - 0.70 U - 0.37

Roll-Up or sliding R - 10 U - 0.50 U - 0.50

Upward-Acting or Sectional N / A N / A R - 10

Note:• 2009 IECC / ASHRAE 90.1 only provides U-Factors• Upward-Acting or Sectional is new and unique to VT code


Note:

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Building Envelope - FenestrationCategory 2005 CBES 2009 IECC 2011 CBES

Vertical Fenestration (Maximum %) 50% 40% 40%

Framing Materials other than Metal with or

without Metal Reinforcement or

Cladding U-0.35 U-0.35 U-0.35Metal framing with or without Thermal Break

Curtain Wall/Storefront U-0.45 U-0.45 U-0.42Entrance Door U-0.80 U-0.80 U-0.80

All Other U-0.50 U-0.55 U-0.50SHGC-All Frame Types

PF < 0.25 U-0.40 U-0.40 U-0.400.25 < PF < 0.5 U-0.55 NR U-0.55

PF >= 0.5 NR NR NRSkylights (Maximum %) 5% 3% 3%

Skylights, Glass U-0.60 U-0.60 U-0.50 SHGC-0.40 SHGC-0.40 SHGC-0.40

Skylights, Plastic U-0.60Plastic Not Specified

SHGC-0.62Plastic Not Specified

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502.4. Air Leakage— 2005 CBES and 2009 IECC: broad language— 2011 CBES: Mandatory continuous air barrier

Air barrier compliance options– Option 1: Materials– Option 2: Assemblies– Option 3: Building Test (0.31 cfm/ft2 of shell area @ 50

Pa) Air Barrier penetrations-explicit language on air sealing Fenestration air leakage table

Context

• Substantial part of joint DOE/NBI/AIA proposal to 2012 IECC

• Originally adapted from MA building code, so “field-tested” and regionally appropriate

Building Envelope

56

502.4.7 Vestibules1. Revised to reflect changes in proposed 2012 IECC

a. Utilizes new definition of “Building Entrance”2. VT - specific:

a. If vestibule is tempered, max temperature setting of 55° F; Cooling prohibited

b. If tempered, shall be constructed according to envelope provisions

c. If tempered, thermostat shall be programmable and inaccessible to public

Context1. Improved language from model IECC codes2. TAP recommended changes due to extensive issues with

energy use due to heating and cooling of vestibules

Building Envelope

SECTION 503BUILDING MECHANICAL

SYSTEMS

57

Building Mechanical Systems

Overview of changes due to 2009 IECC

• Revises equipment efficiency tables for water-chilling packages; minimum equipment efficiencies changed

• Requires snow melt control

• Requires demand control ventilation (DCV) for certain spaces

• Removes exception for energy recovery ventilation for lab fume hood systems ≤ 15,000 cfm

• Lowers the system capacity for economizer requirement for most climate zones

• Introduces fan power limitations

• Introduces supply air temperature reset controls for multiple-zone systems

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1. 503.1.2 Electric Resistance Space Heating— Prohibition on electric resistance space heating

a. Carried over from 2005 VT CBES

2. 503.2.5 Ventilationa. References ASHRAE 62.1-2007 rather than IMCb. Added language emphasizing ventilation rates to be

based on expected occupancy levels versus default IMC / ASHRAE 62.1 rates

Context1. Important prohibition on electric resistance heating

that has worked for VT2. Prevents designers from using worst-case

ventilation rates when better information is available


60

503.2.5.2: Demand Controlled Ventilation

• 2005 CBES had no DCV requirement

• 2011 CBES (2009 IECC): DCV must be provided for each zone with spaces > 500 ft² and average occupant load > 40 people / 1000 ft² of floor area where HVAC system has: An air-side economizer, or Automatic modulating control of outdoor air damper, or Design outdoor airflow > 3,000 cfm

Demand control ventilation (DCV): ventilation system capability that provides for automatic reduction of outdoor air intake below design rates when actual occupancy of spaces served by system is less than design occupancy


61

503.2.7: Duct and Plenum Insulation and Sealing

• 2005 CBES (Also 2009 IECC): Minimum R-5 (unconditioned space) and R-8 (outside building)

• 2011 CBES : “All supply and return ducts located in unconditioned spaces shall be insulated to meet same R-value requirement that applies to immediately proximal surfaces.”

Context: Altered to align with RBES

• Public comments raised to address this language—Clarify—Feasibility


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503.2.10: Systems Performance Verification and Completion 1. Buildings ≥ 50,000 SF2. Requirements for independent, third-party

commissioning agents to perform basic functional testing to verify efficient “as-designed” operation of systems specified in other parts of code, limited to:

a. Economizersb. VAV fan controlc. Part-load hydronic controls

3. Prescriptive testing requirements

FAIL


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503.2.10 Systems Performance Verification and Completion (Continued)

Context1. 2012 IECC dedicates separate chapter to commissioning

(Cx) requirements2. Cx for buildings > 50K ft2 as starting point for code

requirements3. Current proposal provides testing ground for future Cx

requirements in VT, utilizing only large buildings4. Feedback from use of 2012 IECC and VT requirements will

be helpful for next update of VT code5. Performance verification should ensure systems comply with

code intent and operating at maximum energy efficiency6. Performance verification improves building performance,

hopefully reduces contractor call-backs, issues


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Revised 503.3.1 Economizers and 503.4.1 Economizers (Complex HVAC Systems)1. Economizers required on all systems ≥ 54,000 Btu / h (2005

CBES ≥ 65,000 Btu/h)2. Defined allowable economizer sequences to align w/ASHRAE 90.1-

20073. Clarified section 503.4.1 using improved language from 2012 IECC

proposalsa. Design Capacityb. Maximum Pressure Dropc. Integrated Economizer Control

Context1. Matches 2009 IECC capacity threshold2. Need to clarify 2005 VT CBES and Economizer sections in 2009

IECC vague3. National IECC code also using these changes to align w/ ASHRAE

90.1


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503.4.2 VAV Fan Control / 503.4.3 Hydronic Systems Controls / 503.4.3.6

1. Added: 503.4.2.1 Static Pressure Sensor Location language

2. Revised: 503.4.3.4 Hydronic variable flow systems language

3. Added: 503.4.3.6 Chilled and Hot Water Temperature Controls

Context1. Language not in 2009 IECC but existed in

ASHRAE 90.1-20072. Language taken from 90.1-20073. Language taken from 90.1-2007


SECTION 504SERVICE WATER

HEATING

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Service Water Heating

504.1.1 Electrical Water Heating LimitationAdded: Electric service water heating units shall be

limited to a maximum of 5 kW total power input

Context: Carried over from 2005 VT CBESES

Yes, that is David Hasselhoff

SECTION 505ELECTRICAL POWER AND

LIGHTING SYSTEMS

68

Major changes to electrical power / lighting due to 2009 IECC

• Adds high-efficacy lighting requirement for dwelling units

• Requires separate controls for daylight zones

• Allows for use of photocell in tandem with other controls on certain exterior lighting applications

• Adds exempted lighting applications that can be excluded from total connected interior lighting power calculations

• Revises additional lighting power allowance calculations for retail areas

• Creates four exterior lighting zones based on lighting need

69

Electrical Power and Lighting

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Interior Lighting Power Allowances1. Building Area Method and Space by space Method

included2. LPD values taken from proposed 2012 IECC values

Context1. 2005 VT CBES contained both methods but 2009

IECC still only used Building Area Methoda. 2012 IECC will have both methods

2. 2005 VT CBES values identical to 2009 IECCa. 2012 IECC values include revised categories,

higher efficiency for certain categories, and scaled back values for others

b. 2011 VT CBES will be aligned with 2012 IECC and ASHRAE 90.1-2010


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• Interior Lighting Power Allowances— Changes to Building Area Method Spaces

— All others unchanged from 2005 CBES— Some changes in space-by-space types:

Revised categories, higher efficiency for certain categories, and scaled back values for others

2005 CBES

2009 IECC 2011 CBES

Office 1.0 1.0 0.9

Retail 1.5 1.5 1.4

Fire Station 1.0 1.0 0.8

Warehouse 0.8 0.8 0.6


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Motors and Transformers1. Added NEMA efficiency tables for motors2. Added NEMA efficiency tables for transformers

Context1. VT CBES included these. Maintained in 2011 VT

CBES. Motor tables are included in ASHRAE 90.1-2007.

2. VT CBES included these. Maintained in 2011 VT CBES.


73

Questions?

residential building energy standards (rbes) and commercial building energy standards (cbes) updates...

Documents

rbes slide

rbes administration

insulation slide

vermont dps slide

rbes table of contents

existing building section

vt rbes arra requirements

code update process