Life Cycle Assessment and the LEED® Green Building Rating System™
Dr. James L. Hoff, DBA
TEGNOS Research, Inc. /
Center for Environmental Innovation in Roofing
Originally Presented at the RCI 23rd International Convention & Trade ShowMarch 2, 2008Phoenix, AZ
Background
The U.S. Green Building Council (USGBC)
• Over 11,000 member organizations
• Mission: “Transform the way buildings are designed, built and operated”
• Sponsor of Greenbuild, the world’s largest green building convention
• Founded the LEED® Green Building Rating System™ in 2000
Background
The LEED® Rating System
• Sets a “nationally accepted benchmark for the design, construction, and operation of high performance green buildings”
• Gives building owners a tool for “immediate and measurable impact on their buildings’ performance”
• Provides a roadmap for “measuring and documenting success for every building type and phase of a building lifecycle”
Background
The LEED® Rating System
• A comprehensive but simple approach focused on five key concepts:
– Sustainable Building Sites
– Water Efficiency
– Energy Efficiency / Atmospheric Impact
– Sustainable Materials Selection
– Indoor Environmental Quality
Background
The LEED® Rating System
• Different forms for different building types and phases of the building lifecycle:
– LEED for New Construction / Major Renovations
– LEED for Existing Buildings and Maintenance
– LEED for Commercial Interiors
– LEED for Core & Shell
– LEED for Homes (Pending)
– LEED for Neighborhoods (Pending)
Background
The LEED® Rating System
• A weighted scoring system based on relative importance of each key element:
Sustainable SitesWater EfficiencyEnergy / AtmosphereMaterials / ResourcesIndoor Environ. QualityInnovation / Design
14 Points5 Points
17 Points13 Points15 Points
5 Points69 Points
LEED Certified:LEED Silver:
26-32 pts.33-38 pts.
LEED Gold:LEED Platinum:
39-51 pts.52-69 pts.
The LEED® Rating System
Advantages of LEED
• Promotes the “Big Picture”
• Keeps it Simple
• Fosters Competition
• Builds Green Awareness
The LEED® Rating System
Limitations of LEED
• Limited Reach– Less than 2% of all buildings since 2000 have achieved certification
• Potential for Confusion
– “Is your roof LEED-approved?”
• Inadequate Emphasis on Durability
LEED, Roofing & Durability
Looking Back to 1970:
OPEC oil embargo• Quality of roofing asphalt decreased as
more gasoline was extracted from every barrel of oil
• Roofing asphalt became more brittle, less plastic
Asbestos • Traditional roofing “felts” relied on
asbestos fibers for strength
• Asbestos fibers replaced by lower strength organic (paper) fibers
Thicker insulation caused “thermal shock” as surface temperatures varied by over 1500 F in a single day…
… causing roof membranes to age prematurely.
LEED, Roofing & Durability
Looking Back to 1970:
New material alternatives were introduced…
… but with a steep learning curve and some initial failures
LEED, Roofing & Durability
Looking Back to 1970:
“With the green building movement still in its infancy, the construction industry is rushing to promote ‘green’ products with all the excitement that comes with building a new market. History shows us, however, that while we must move forward with innovation and excitement, we must also take care to be responsible market stewards. ‘Green’ products manufacturers should be careful to provide defendable proof that these products perform as stated.”
Kenneth Mentzer, President, North American Insulation Manufacturers Association. Building Design and Construction “White Paper on Sustainability”, 2003, p. 13.
LEED, Roofing & Durability
Looking Back to 1970:
LEED & Durability
The USGBC and LCA
• LCA working group established in 2005
• LCA guidelines published January, 2007
• Formal implementation proposed for 2008-2009
• Informal implementation started in 2007 by adding several proprietary rating systems under Innovation / Design credits.
Life Cycle Assessment
What is LCA?• A scientific approach to evaluating the environmental
impact of a product throughout its life cycle.
– Scientific Approach: Based on measurable and predictable attributes
– Focused on Impact: What is the net result to the environment?
– Throughout the Life Cycle: A “cradle-to-grave” – or “cradle-to-cradle” approach
Life Cycle Assessment
The Product Life Cycle
Source: Life Cycle Assessment: Principles and Practice. Scientific Applications International Corporation, 2006, p.1.
Raw Materials Acquisition
Manufacturing
Use / Re-use / Maintenance
Recycling / Waste Mgmt.
Inputs:
Raw Materials
Energy
Outputs:
Atmospheric Emissions
Waterborne Waste
Solid Waste
Co-Products
Other Releases
System Boundary
Processes:
Life Cycle Assessment
Environmental Impacts
Impact:
Global Warming Potential (GWP)Ozone Depletion Potential (ODP)Photochemical Oxidant Potential (PCOP)Acidification PotentialEutrificationHealth Toxicity (Cancer)Health Toxicity (Non-Cancer)Health Toxicity (Air Pollutants)Eco-Toxicity PotentialFossil Fuel Use
Measure:
kg CO2 Equivalentkg CFC Equivalentkg NOX EquivalentH+ Moles Equivalentkg Nitrogen Equivalentkg Benzene Equivalentkg Toluene Equivalentkg: DALYs Equivalentkg 2,4-D EquivalentmJ Surplus Energy /mJ Extracted Energy
Source: EPA Tool for the Reduction and Assessment of Chemical and other Environmental Impacts (TRACI)
EPA “Top-Ten” Environmental Impacts
Life Cycle Assessment
The LCA Process• Three Basic Steps
– Compile inventory of relevant inputs / outputs
– Evaluate the impacts associated with each input / output
– Interpret the results to help make informed decisions
• A Comparative Approach: Not Absolute
– Typically used to choose among alternatives and drive continuous improvement
– Example: 1970 Coca-Cola LCA
Life Cycle Assessment
LCA Benefits
• Avoids Shifting of Impacts
• Allows Consideration of Trade-Offs
• Promotes Situation-Based Decisions
Life Cycle Assessment
LCA Benefits
Building Construction Examples:
Limestone Concrete v. Fly Ash Concrete (USA)
Plastic Insulation v. Mineral Wool & Cork (Europe)
Life Cycle Assessment
LCA Limitations
• Expensive: Takes Time & Money
• Complex: Difficult to Understand & Communicate
• For Reference Only: Cannot by Itself Determine Cost-Effectiveness or Practicality
Life Cycle Assessment
LCA Limitations
Building Construction Example:
Use of Cover Boards in Insulated Roof Assemblies
Life Cycle Assessment
LCA, LCC, and Durability
LCA not focused on durability as directly as Life Cycle Cost (LCC)…
…but LCA may be a more accurate approach to LCC if long-term environmental impact is the best economic measure of construction cost
Life Cycle Assessment
LCA, LCC, and Durability
Building Construction Example:
20-Year “Eco-Friendly” Roof v.
30-Year Traditional Roof
Life Cycle Assessment
Current Status of LCA
• Part of ISO 14000
– Standard for Environmental Management
– Similar to ISO 900 Standard for Quality Management
– Describes how LCA should be used to evaluate products
– Describes how LCA should be communicated (Environmental Product Declaration or EPD)
Life Cycle Assessment
Current Status of LCA
• Growing Rapidly in Europe
– Hundreds of EPDs currently in place for construction products
– Driven by global manufacturers seeking the highest common denominator to simplify product lines
Life Cycle Assessment
The Future of LCA
• ISO 14000: The new global model– ISO 14000 has been endorsed as the basic model for managing
environmental impacts
– Almost all major global companies are seeking ISO 14000 registration for facilities – and this will carry over to products
• EPD: The new MSDS– Specifiers will require EPDs or similar data for all products
Life Cycle Assessment
Short-Term Impact on the Roofing Industry
• Confusion Will Reign
– ISO 140OO is a standard method – not a standard
– USGBC’s ‘kick-start” endorsement of different proprietary approaches will only add to the confusion
• The Early Adapters Will Make the Rules
– New attachment technologies
– Industry recycling programs
Life Cycle Assessment
Long-Term Impact on the Roofing Industry
• LCA will favor thinner, stronger products
– Lightweight membranes
– Lightweight foam insulations
• LCA will favor systems that can be installed quickly – and removed & recycled quickly
– New attachment technologies
– Industry recycling programs
Life Cycle Assessment
What Can the Roofing Industry Do?
• Get Educated and Involved
– Be prepared to address the coming confusion
– Be prepared to assure that durability is a key consideration
Life Cycle Assessment
What Can the Roofing Industry Do?
• Consider Industry-Wide LCA / EPD Programs
– Establish a common baseline of generic product groupings
– Support differentiation and competition above the baseline
Life Cycle Assessment
What Can the Roofing Industry Do?
• Support the new Center for Environmental Innovation in Roofing
– Broad-based industry voice for green building education, research, and advocacy
– Washington-based for policy effectiveness
"As an industry, we have spent far too much time and far too many dollars fixing past problems related to durability not to become unflinching advocates for the utmost importance of durability in any green building initiative.”
James L. Hoff. “Advancing Sustainable Roofing: LEED and the Commercial Roofing Industry." Proceedings of the 20th International Convention of the Roof Consultants Institute, Miami Beach, Florida, March, 2004.
Life Cycle Assessment and LEED
The Roofing Industry Challenge