environmentally conscious building material...

Environmentally Conscious

Building Material Selection

(USEPA)

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© Canadian Wood Council 2012

Canadian Wood Council, Wood WORKS! and the Wood Solutions Fair is a

Registered Provider with The American Institute of Architects Continuing

Education System. Credit earned on completion of this program will be reported

to CES Records for AIA members who complete a participation form at the

registration counter. Certificates of Completion for non-AIA members are

available on request.

This program is registered with the 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.

Program Education Credit Information

Presentation Outline

• Motivations & navigating the current landscape

• Environmental evaluation tools for buildings

• Three S’s of carbon (sink, storage, & substitution)

• Online carbon calculators for wood buildings

• Environmental product declarations (EPD)

• Building product analysis based on LCA

– BEES & ATHENA

• Wood building products of today & tomorrow

6

Motivations – Sustainable Environment

• Construction and operation of buildings are responsible for: • 40% of global energy use

• 30% of anthropogenic GHG emissions worldwide

• ICI building sector is 4th largest GHG emitter in Canada

• Energy and resource use is outpacing population growth

• Increasing life cycle performance of buildings offers high environmental returns for low economic investment

An Evolving Landscape for Wood Products

• IPCC – 6,000+ scientists - climate change is reality

• LCA – full life cycle accounting

• EPD – product specific environmental information

• Rating Tools (LEED, Green Globes, etc.)

• Energy use (embodied vs. operational)

• Water – the next carbon

• Impacts – known but not quantified, unknown/unintended

Green design choices are complex

Rising Importance of Embodied Material Impacts

(PE International)

Rising Importance of Embodied Material Impacts

(CPA, 2012) (Architect: Richard Rogers)

• Building Code

– NBCC minimum requirements for construction

– IgCC & CalGreen have codified green building practices in U.S.

• Green Building Rating Systems & Challenges

– LEED®, Green Globes, Living Building, Architecture 2030

– Focus on energy & water use, materials, site selection

– Most are points based systems

Whole-Building Evaluation Tools

• Life Cycle Assessment (LCA)

– Scientific-based, objective evaluation methodology

– Based on environmental modeling of impacts

– Potential impact indicators (GWP, eutrophication, acidification, ozone depletion, etc.)

– Multi-criteria decision analysis (trade-offs)

Whole-Building Evaluation Tools

(Tackle Climate Change, Use Wood)

(USEPA)

(JRC-EU)

• What is wood?

– CO2 + H2O + Sunlight Sugars Cellulose (Wood) + O2

– Wood is 50% carbon by dry weight

(a natural carbon storage device)

• As a building material:

– Anisotropic (strength varies in each direction)

– Hygroscopic (stores or releases moisture to external environment, i.e. shrinks & swells)

– High thermal resistance properties

(resulting from trapped still air)

Wood – A Natural Building Material

(Wood Handbook)

Three S’s of Carbon – Forests as Sinks

• Carbon flows

– Forest cover has remained constant for last 100 yrs.

– Sustainable management is paramount

– Carbon protocols/accounting (e.g. offsets, credits)

(Tackle Climate Change, Use Wood)

• Wood products & building systems have ability to store large amounts of carbon (CO2 eq.)

• 1 m3 of S-P-F stores ̴ 1 tonne of CO2 eq.

• Amount of carbon stored ∞ wood density

Three S’s of Carbon – Storage

(Johal)

(APA)

Three S’s of Carbon – Substitution

• Wood products can substitute for other more carbon-intensive building materials

• Embodied emissions are avoided by using wood

• Displacement factors (kg CO2 avoided/kg wood used) can be estimated to calculate carbon avoided

• EPDs (based on LCA) will play an increasing role in selecting materials that minimize potential environmental impacts

– “Mitigating options by the forest sector include extending carbon retention in HWP, product substitution, and producing biomass for bioenergy.”(2007)

– “In the long term, a sustainable forest management strategy aimed at maintaining or increasing forest carbon stocks, while producing an annual sustained yield…will generate the largest sustained mitigation benefit.” (2007)

– “We stress the importance of…sustainable forest management objectives and practices…” (Rio+20, 2012)

IPCC Recommendations

• Sustainable forest management is imperative to obtain long-term carbon benefits

• Optimization of harvested forest products

Impacts on Carbon Profile

• End-of-life options for wood products:

(CEI-Bois/EPF)

Impacts on Carbon Profile

• Energy recovery • Recycle

• Disassembly & reuse • Landfill

Material Net Carbon

Emissions

(kg C/metric ton)

Framing lumber 33

MDF (virgin fiber) 60

Brick 88

Glass 154

Recycled steel

(100% from scrap) 220

Concrete 265

Concrete block 291

Recycled aluminum

(100% recycled content) 309

Steel (virgin) 694

Plastic 2,502

Aluminum (virgin) 4,532 1/ Values are based on life cycle assessment and include gathering and processing of raw materials, primary and secondary processing, and transportation. 2/ Source: USEPA (2006).

Net Carbon Emissions in Producing a Tonne1,2 of:

• www.cwc.ca Resources Electronic Tools

Online Carbon Calculators For Wood Buildings

Carbon Estimator – Generic Analysis

• www.cwc.ca Resources Electronic Tools

Online Carbon Calculators For Wood Buildings

Carbon Calculator – Detailed Analysis

(ESSB, Vancouver – Perkins + Will)


Siding & Roofing species: Western Red Cedar/Eastern White Cedar

• Results are approximate & refer only to carbon storage & savings attributed to wood materials

– Detailed LCA required to determine the life cycle carbon footprint of a building

– Other environmental impacts are not considered

• Avoided emissions calculation – “what if”

a) Building would be constructed with other materials

b) The exact type of alternative materials

c) Fate & disposal methods of materials at end-of-life

Calculator Assumptions & Limitations

• 8,500 ft2 library & community hall

• Includes sawn lumber, I-Joists, LVL & OSB

Levitt Goodman Architects Ltd.

Case Study – Bridgenorth Library, ON

• 400,000 board feet of FSC-certified glulam (2010 FSC award winner) • Torrefied aspen for exterior ceilings & façade accents • Design inspired by IPCC report recommending the use of wood building products

instead of concrete or steel to mitigate climate change effects

GHA Architecture et Developpement

• 6-storey office building • Performance-based

alternative solution • 60,000 ft2 of floor area

Carbon Case Study – Fondaction, QC

• Originally conceived as a concrete structure – put on hold due to cost

• Redesigned in wood after 2009 BCBC changes allowed for 6-storey wood-frame construction

JM Architecture

Carbon Case Study – Library Square, B.C.

• 6-storey mixed-use • 35,500 ft2 library + retail • 150 condominium units

• Labels conveying LCA-derived environmental impact data about products

• Similar to nutrition labels on food products

• Transparently discloses standardized data about the potential environmental impacts

• Enables side-by-side comparison of products

• Simple & user-friendly mechanism to bring LCA data into the marketplace

Environmental Product Declarations (EPD)

Types of Eco-labels

• ISO defines Types I, II and III eco-labels

Types of Eco-labels

• Type I:

– Third-party verified that a product meets multiple criteria, which have been established by the certifier (e.g. Canada’s EcoLogo™ program)

• Type II:

– Self-declaration, which addresses a single environmental attribute (e.g. recyclability, energy)

• Type III (EPD):

– Not a “seal of approval”, but LCA generated data adhering to a specific ISO-defined methodology

– Transparent communication of multiple impacts

Data for ½” x 6”, Clear Grade, Painted

EPD for Western Red Cedar Bevel Siding

• EPDs currently under development (scheduled for 2013 release) 1. Softwood lumber

2. Plywood

3. OSB

4. Glulam

5. LVL

6. I-Joists

7. Preservative treated lumber (ACQ & Borate)

• Data averaged for North American production

EPDs for North American Wood Products

• Developed by NIST in conjunction with USEPA

• Measures environmental performance of 230 building products using LCA data

– Provides detailed information on life cycle stages, maintenance assumptions, & referenced data

• Measures economic performance using ASTM life-cycle cost method

• Allows for side-by-side product comparisons (environmental, economic or multi-attribute)

Building for Environmental & Economic Sustainability (BEES)

BEES – Analysis Parameters

Products organized as per ASTM UNIFORMAT II classification

BEES – Select Alternatives

Based on functional unit

BEES – Reporting Results


Hydropower, wind, nuclear, geothermal, & biomass are considered renewable


Feedstock energy: potential energy which is easily available at end-of-life

Fuel energy/process energy: energy released when fuels are combusted

Publicly available at:

http://www.nist.gov/el/economics/BEESSoftware.cfm

• Excel-based spreadsheet tool

• Contains pre-defined building envelope & assembly configurations for both commercial (low-/high-rise) & residential building types

• User simply inputs the square footage of the assembly & the program outputs the embodied environmental impact results

• User is limited to the pre-defined assemblies & has no ability to modify or customize

• Inputs & results are regionalized for Canada

ATHENA EcoCalculator

• Stand-alone program that allows users to create & model their own custom assemblies & envelope configurations

• Allows for more accurate modeling of proposed designs or existing buildings

• Some technical knowledge of building components is required

• Not an energy simulation tool, but does allow input of operational energy simulation effects to be displayed alongside embodied impacts

ATHENA Impact Estimator

ATHENA Impact Estimator – Custom Wall

ATHENA Impact Estimator – Floors & Roof

ATHENA Impact Estimator – Reports

Impact Estimator – Design Comparison

Available for free:

http://calculatelca.com

(Bunting Coady Architects, 2007)

Whole-Building LCA Comparison

Discovery Place – Building 12 (Burnaby, B.C.)

Full study available at (http://hdl.handle.net/2429/36433)

62

Motivations – Provincial Legislation

• B.C. Building Code changes (Spring 2009)

– BCBC now allows wood-frame construction up to six-storeys in height

– Opportunity for wood construction to have a larger presence in the ICI building sector

• B.C. Wood First Act (Fall 2009)

– Requires publically funded buildings to consider wood as the primary building material

– Adopted by 40+ municipalities in the province

• Worst outbreak in recorded history

• 70% of B.C.’s lodgepole pine trees are infected

• 35 billion ft3 of timber expected to be killed

• B.C. forests are currently net emitters of CO2

• Epidemic spreading east across Boreal & south into United States

• Feasible mitigation strategies include development of innovative building products & construction systems using MPB-killed timber (e.g. CLT, hybrid structures)

63

Motivation – Mountain Pine Beetle

(Martinsons, 2006)

Concrete shear cores Glulam frame & CLT diaphragm

(Karacabeyli, 2009)

(Lam & Chen, 2007)

Methodology – Timber Redesign

Locally manufactured MPB-killed CLT

Concrete Design Timber Design

Exterior Wall Assembly

Thickness (mm) 321 196

RSI (m2K/W) 1.56 1.57

Built-up Flat Roof


RSI (m2K/W) 2.68 2.70

Curtain Wall Assembly (incl. insulated spandrel panel)


RSI (m2K/W) 1.38 1.39

65

Exterior Envelope Comparison

66

Methodology – Life Cycle Assessment

• Cradle-to-gate study boundary

• 50-year building lifetime horizon

• Focus was on building structure & envelope only

• Operational energy use not considered (envelope R-value equivalency maintained in both scenarios)

• Secondary data obtained from BEES® v4.0, ATHENA® & US LCI

• North American specific LCIA characterization tool utilized (TRACI)

Results – Potential Environmental Impacts

70

(Structurlam)

Sensitivity Analysis

• 15% vs. 20% fly ash concrete mix

– Less than 2% improvement in 4 impact categories

• Variation of ± 10% in laminated timber quantity

– Demonstrated ± 1–4% change in all but 3 categories

– GWP of timber design improved with more wood

• On-site construction: timber design appears superior

• End-of-life: timber design has additional choices

Wood Products Today

Wood Products Tomorrow Cross Laminated Timber (CLT)

(Waugh Thistleton) (Forté)

(Structurlam)

Hybrid & Mass Timber – Tall Wood Buildings

Wood Products Tomorrow

(mgb Architecture)

What Lies Ahead

This concludes the:

• American Institute of Architects

Continuing Education Systems Program

ENVIRONMENTALLY CONSCIOUS

BUILDING MATERIAL SELECTION

Canadian Wood Council

Adam Robertson, M.A.Sc., EIT

[email protected]

Questions/ Comments?

Canadian Wood Council G063

Environmentally Conscious Building Material Selection – LCA CALWSF_01

Adam Robertson M.A.Sc., EIT December 13, 2012

Credit(s) earned on completion of this course 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 course 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.

This presentation will cover the topic life cycle assessment (LCA), as it relates to building products, systems, and design. The current standards and codes that regulate environmental impact assessment of building products will be discussed, along with the development of environmental product declarations (EPD) for the Canadian and American wood products industries.

Course Description

Learning Objectives

1. The current standards and codes that regulate

environmental impact assessment of building products will be discussed, along with the development of environmental product declarations (EPD) for the Canadian and American wood products industries. 2. The most significant LCA-based design tools for environmentally conscious building material selection, including BEES online, ATHENA® Impact Estimator for Buildings and EcoCalculator for Assemblies, as well as the online Carbon Calculator for Wood Buildings, will be examined. 3. This presentation reviews a case study project that used LCA to compare the environmental impacts of a mid-rise office building structure, designed using either heavy timber (glulam and cross laminated timber) or cast-in-place reinforced concrete. 4. This presentation will cover the topics of life cycle thinking and life cycle assessment (LCA), as they relate to building products, systems, and design.

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

This concludes The American Institute of Architects Continuing Education Systems Course

Canadian Wood Council Wood WORKS! Alberta

www.cwc.ca www.wood-works.org

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