2. Life Cycle Assessment and the Building Envelope: Balancing Durability & Environmental Impact Dr. James L. Hoff Center for Environmental Innovation in Roofing

3. Agenda Sustainability: Balancing Time & Impact Life Cycle Assessment Durability LCA and Durability: Critical Issues Durability Tools for a Sustainable Future Recommendations Going Forward

4. What is Sustainability? “A state that can be maintained at a certain level indefinitely” (Merriam-Webster Online Dictionary) “Meeting the needs of the present without compromising the ability of future generations to meet their own needs” (U.N. Brundtland Commission, 1987)

5. Measuring Sustainability When evaluating the relative sustainability of a product or a system, the key questions are: Sustainability = Impact Time 1.How long (time) can the product or system last? 2.What is the cost (impact) to last that long?

6. Sustainability: The Core Issue TIMEIMPACT Balancing Impact and Time

7. Looking at Impact: Life Cycle Assessment (LCA) Looking at Longevity: Durability

8. What is LCA? “… a scientific approach to identify and evaluate the environmental impact of a product throughout its life cycle.” Office of the Federal Environmental Executive (OFEE) http://ofee.gov/gs/gs.asp

9. What is LCA? A Scientific Approach: Based on measurable and predictable attributes To Identify & Evaluate: Intended to compare alternatives, not provide absolute values Focused on Impact: What is the net result to the environment? Throughout the Life Cycle: A “cradle-to-grave”… or “cradle-to-cradle” approach

10. Why is LCA Important? LCA is a globally recognized procedure based on established ISO standards LCA will be incorporated into the LEED ® Green Building Rating System in 2010 / 2011 LCA is a necessary measure to support emerging global warming initiatives such as carbon cap-and-trade

11. 1.Establish the Time Period 2.Describe the Life Cycle System 3.Identify & Measure the Impacts 4.Assess the Impacts Key LCA Steps

12. 10 Years 15 Years 20 Years 30 Years 39 ½ Years 60 Years Typical Commercial Roof Warranty Length U.S. Taxable Building Depreciation Period USGBC Life Cycle Task Force Recommendation Step 1: Establish the Time Period

13. Step 2: Describe the Life Cycle System Inputs Processes Outputs System Boundary

14. Raw Materials Acquisition Manufacturing Operation / Maintenance Recycling / Waste Mgmt. Inputs: Raw Materials Energy Outputs: Atmospheric Emissions Waterborne Waste Solid Waste Co-Products Other Releases System Boundary Processes: Transportation & Handling Installation / Assembly The Product Life Cycle Time Impact

15. Step 3: Measure the Impacts Identify the Significant Impacts Establish Meaningful Measures

16. Impact: Global Warming Potential Ozone Depletion Potential Photochemical Oxidant Potential Acidification Potential Eutrification Health Toxicity (Cancer) Health Toxicity (Non-Cancer) Health Toxicity (Air Pollutants) Eco-Toxicity Potential Linked To: Global Climate Change Degradation of Ozone Layer Ground-Level Ozone Acid Rain Algae Blooms Cancer Frequency Non-Cancer Disorders Breathing-Related Illnesses Reproductive & Genetic Disorders Measuring Environmental Impacts The TRACI Model

17. Measuring Environmental Impacts The TRACI Model Meaningful Measure: kg CO 2 Equivalent kg CFC Equivalent kg NOX Equivalent H+ Moles Equivalent kg Nitrogen Equivalent kg Benzene Equivalent kg Toluene Equivalent kg: DALYs Equivalent kg 2,4-D Equivalent Impact: Global Warming Potential Ozone Depletion Potential Photochemical Oxidant Potential Acidification Potential Eutrification Health Toxicity (Cancer) Health Toxicity (Non-Cancer) Health Toxicity (Air Pollutants) Eco-Toxicity Potential

18. Weigh the Impacts –Which impacts are most important in the assessment? Compare Alternatives –Which alternative provides the optimal benefit? Look for Improvement Opportunities –How can the impacts be reduced? Step 4: Assess the Impacts

19. Avoids Shifting of Impacts Allows Consideration of Trade-Offs Promotes Situation-Based Decisions LCA Benefits

20. LCA Limitations LCA is Expensive –Requires time & money LCA is Complex –Difficult to understand & communicate LCA is Not Absolute –Useful for reference or comparison –Cannot by itself determine cost- effectiveness or practicality

21. What is Durability? A dictionary definition: “… the ability to exist for a long time without significant deterioration.” Merriam-Webster Online Dictionary

22. What is Durability? A building standards definition: “… the ability of a building or any of its components to perform its required functions in its service environment over a period of time without unforeseen cost for maintenance or repair.” Canadian Standards Association “Guideline on Durability in Buildings” (CSA S478-95, Rev. 2001)

23. The ability of a building or any of its components to: 1.perform its required functions 2.in its service environment 3.over a period of time 4.without unforeseen cost for maintenance or repair What is Durability?

24. Roof Durability Characteristics Performing Required Functions Resist and re-direct moisture Resist air & vapor movement Resist thermal transfer Resist fire, wind, hail, and other loads Serve as a working platform for: –Rooftop mechanical equipment –Solar / PV installations –Garden roofing installations

25. Roof Durability Characteristics In Its Service Environment Climatic Environment –High wind / wind-blown debris zones –Severe hail zones –Cold climates / severe freeze-thaw zones –Warm climates / high uv zones Operating Environment –Frequency / density of use –Occupant capabilities / attitudes –Frequency / complexity of maintenance

26. Roof Durability Characteristics Over a Period of Time Period of Time = Intended Service Life

27. Roof Durability Characteristics Without Unforeseen Cost Implies Some Level of Cost Should Be Foreseen! Implies Planning Is Necessary!

28. “The majority of green building assessment systems focus on the design of the constructed building, with little focus on the effect of the building system’s life during operation. This tendency has resulted in a failure of many rating systems to properly consider durability, lifecycle cost, and the effects of premature building envelope failures.” Durability & Green Rating Systems “Green Assessment Tools: The Integration of Building Envelope Durability. “ (McCay, 2008, p. 1)

29. Too much focus on design, too little focus on operation…... resulting in a failure to address: –True life cycle cost –Risk of premature failures Durability & Green Rating Systems

30. Incorporating Vital Service Features into LCA Incorporating Realistic & Achievable Service Life Expectations into LCA Balancing Impact &Durability: The Key Issues

31. Example: Installing a High Density Cover Board over Low Density Roof Insulation Membrane Cover Board Insulation Environmental Benefits: +Reduced Damage +Longer Service Life +Lower Life Cycle Impact Environmental Costs: –Added Materials –Added Energy –Added Waste Balancing Impact & Durability Vital Service Functions

32. Thicker roofing membranes Redundant flashing details Will the LCA recognize the added value of such enhanced service features? Balancing Impact & Durability Vital Service Functions Other Examples:

33. Balancing Impact & Durability Service Life Expectations How do we identify service life today? Anecdotal field reports Opinion surveys Historical end-of-service studies Agency approval reports Manufacturer warranty offerings

34. Opinion Survey 1 16.6 N/A 2 14.1 No Data System Type Asphalt BUR SBS Modified PVC EPDM TPO Historical Study 3 13.6 17.3 N/A 2 16.8 – 18.4 No Data Agency Report 4 20 35 20 Warranty Offering 5 20 15 30 Data Source 1 Mean service life from Cash (1997), based on an opinion survey of industry participants. 2 Data from the Cash & Schneider studies involved discontinued formulations of PVC that do not allow the data to be meaningful. 3 Mean service life from Schneider & Keenan (1997), based on end-of-service field reports. 4 Estimated service life from British Board of Agrément Technical Approvals (BBA, 2008): 5 Published warranty offerings from NRCA Low Slope Roofing Materials Guide, 2006-07, Vol. 2, Section 5 Roof Membrane Warranties. Service Life Expectation Example: Low-Slope Roofing Systems Estimated Service Life (Years)

35. Different Estimates – Different Assumptions: Time Assumptions –Backward looking: Expecting no change –Forward looking: Expecting improvement Quality Assumptions –Uncontrolled sample: Assuming the worst –Controlled sample: Assuming the best Durability & LCA Service Life Expectations

36. The contrast between forward-looking versus backward-looking service life estimates and average versus high quality levels help identify two critical questions for the building envelope industry: Durability & LCA Where Do We Go From Here? 1.Should we move forward with the assumption that the building envelope components installed on the sustainable buildings of the future will be average in performance, or should the expectation be set higher? 2. And if we decide to move forward with higher expectations, how do we develop and implement processes and controls to assure this higher level of performance is attained?

37. Durability & LCA Durability Tools for a Sustainable Future Performance Standards Durability Planning

38. Durability Tools Performance Standards Prove Their Value through Research –Drawing from the past –Adding certainty to the future. Identify Their Value with Measurement –Providing measurable and reproducible value –Balancing environmental impact with added performance. In order to effectively address vital service functions, performance standards must…

39. Failure Analysis (e.g. Bailey & Bradford field studies) Destructive Testing (e.g. Koontz et al. hail testing) Performance Testing (e.g. ORNL thermal testing) Performance Standards Research Examples & Options (Low Slope Roofing)

40. What is the measurable value (benefit less impact) of: –Multiple & staggered insulation layers? –Cover boards? –Increased membrane thicknesses? –Redundant flashing details? Performance Standards Features Needing Measurable Value:

41. An Up-To-Date & Active Research Agenda –To identify & address the critical “gaps” –To identify resources & funding –To monitor & measure progress A Research-Driven Standards Process –A consensus process … –Using research results to validate industry practice Performance Standards and the Building Envelope What We Need:

42. Durability Tools Durability Planning Emphasis on Process –A management system –Similar to ISO 9000 & ISO 14000 Emphasis on Shared Responsibility –Identifies stakeholders –Identifies roles

43. Durability Tools Durability Planning and Canadian Standard S478-95 Three Basic Steps: 1.Identify Durability Determinants 2.Identify Durability Interventions 3.Develop Action Plan & Timetable

44. Step1: Identify Durability Determinants Providing the Required Functions In the Service Environment By Key System Element Durability Planning Canadian Standard S478-95

45. Step 2: Identify Durability Interventions Durability Planning Canadian Standard S478-95 During Design During Material Selection During Application & Commissioning During Service Life At End of Service

46. Step 3: Develop Action Plan & Timetable Durability Planning Canadian Standard S478-95 Periodic & Ongoing At Critical Specified Times

47. Durability Planning Matrix Durability Planning & Green Building Envelope Design

48. The Service Environment Required Functions System Elements Durability Planning Model Durability Planning Matrix

49. The Service Environment Required Functions System Elements Durability Planning Model Durability Planning Matrix Design Criteria Material Criteria Application Criteria Commissioning Criteria

50. Durability Planning Model Durability Planning Matrix Operating / Maintenance Criteria Ongoing & Periodic At X Years At X+ Years At End of Service System Elements Service Environ.

51. Balancing Impact & Durability Going Forward… Try to reach agreement on realistic, but achievable service life periods that support long-term building sustainability Establish an up-to-date and active industry research agenda Increase research activity, emphasizing key component & detail functions Re-invigorate standards activity with new research & new commitment Begin incorporating durability planning into building envelope specifications Continue to advocate the importance of durability

52. Life Cycle Assessment and the Building Envelope: Balancing Durability & Environmental Impact Dr. James L. Hoff Center for Environmental Innovation in Roofing