Quantifying building sustainability and resilience

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1 Quantifying building sustainability and resilience Jeremy Gregory PNWER Summit Infrastructure Working Group July 18, 2016

2 Sustainability: we want our world to last Ecological These are interconnected systems Social Technical Slide 2

3 Measuring performance of systems Functional Environmental Economic Social Measuring absolute sustainability is difficult We tend to measure trends: Are we moving towards or away from sustainability? Slide 3

4 Measuring performance of systems Functional Environmental Economic We can measure performance during conditions that are: Typical/intended Atypical/unintended Resilience: a system s response to problems Social Slide 4

5 Resilience: a system s response to problems Hazard Resistance Slide 5

6 Buildings are integral to sustainability Ecological Quantifying sustainability performance is essential for progress Social Technical Slide 6

7 Infrastructure & buildings decisions involve trade-offs Performance Analyze and balance trade-offs Environmental impacts Cost Slide 7

8 A life cycle perspective is key for sustainability and resilience decisions Multiple mechanisms for reducing environmental impact and cost Materials Production Use recycled content Reduce energy Improve performance Design & Construction Use less (i.e., stronger) material Create longerlasting designs Use Reduce energy consumption Reduce heat island effects End-of-Life Enable material recovery Plan for component reuse Slide 8

9 Sustainable infrastructure achieved by: Increasing performance Design process Analyze and balance trade-offs Reducing environmental impacts LCA Reducing cost LCCA Slide 9

10 Which is preferred from a life cycle perspective? Lower design standard Lower initial cost Likely worse energy performance Worse hazard resistance Same location Same appearance Higher design standard Higher initial cost Likely better energy performance Better hazard resistance Quantitative information is lacking on economic and environmental benefits of sustainable and resilient construction Slide 10

individual building expenditures for design A and design B over time

11 Present Value of Costs Present Value of Costs LCCA Life-cycle cost analysis: Method for evaluating total costs of ownership 18 Transform individual building expenditures for design A and design B over time into 18 life-cycle cost B A A B 6 0 B B B A A A 0 Life-cycle costs Slide 11

12 Life cycle cost analysis with hazard resistance Build Energy Use Wear & Tear Hazard Repair End of Life Raw materials, labor, equipment, & energy Electricity, gas, and oil consumption throughout life Painting, windows, siding, etc. Combines probability of hazard with damage from hazard Waste and recycling, labor, equipment, & energy Slide 12

13 Expected Cost Probability Probability Probability Probabilistic Hazard Repair Estimation Hazard Curves Fragility Curves Hazard intensity Hazard Intensity Minor Damage model Damage Level Severe Design A Design B Life Cycle Cost Analysis Building Lifetime Slide 13

14 Present Value of Life Cycle Cost (thousands) Key finding: life cycle perspective is important LCC varies by location, discount rate, and hazard resistance $800 $600 $400 $200 Hurricane Earthquake Improvements Maintenance Energy Initial $0 Minimum Enhanced Minimum Enhanced Minimum Enhanced 2 story, 1800sf, wood frame house San Francisco Charleston New Orleans Slide 14

15 Probabilistic LCCA approach enables expected payback period San Francisco, CA Charleston, SC New Orleans, LA No Payback 5 year payback 2 year payback $800 $800 $800 $600 $600 $600 $400 $400 $400 $200 $200 $200 $ Year $ Year $ Year Enhanced resistance design Minimum resistance design Slide 15

16 Present Value Thousands If $250k to build standard house, how much more would you pay for hazard resistance? $300 $250 Mitigation cost 14.3% on top of Initial A $200 $150 $100 $50 $0 20% of Initial A Design A Initial Hazard Design B 5% of Initial B Slide 16

17 Present Value Thousands How much mitigation can you afford in order to break-even across life cycle? $300 $250 Mitigation cost to break even Mitigation $200 $150 Initial A Initial A $100 $50 $0 Hazard Design A Difference in Hazard cost Hazard Design B Hazard Initial A Mitigation Slide 17

3% of Initial A Mitigation $200 $150 Initial A Break Even Mitigation Percent Initial

18 Present Value Thousands How much mitigation can you afford in order to break-even across life cycle? $300 $250 Mitigation cost to break even 14.3% of Initial A Mitigation $200 $150 Initial A Break Even Mitigation Percent Initial A $100 $50 $0 Hazard Design A Difference in Hazard cost Hazard Initial A Mitigation Hazard Design B Slide 18

19 Break Even Mitigation Percent Example: South Carolina wood frame home Comparing mitigation options 2.0% 1.5% 1.0% 0.5% 0.0% Coastal Toenail to Strap Gable to Hip Inland Slide 19

20 Example: Mid-rise non-engineered masonry Break Even Mitigation Percent for enhanced roof Break Even Mitigation Percent % Based on FEMA Benefit Cost Analysis tool Slide 20

21 Example: Mid-rise change in structure Non-engineered wood to Engineered concrete Nonengineered wood Engineered concrete Based on FEMA Benefit Cost Analysis tool Slide 21

22 Mitigation decisions involve many stakeholders Money Info Regulate New Building Owners Mitigate? Architect & Builder Insurance Company Government Agencies Engineers & Code councils Hazard Engineer Consultants & Universities Slide 22

Increasing performance Design process Analyze and balance

23 CSHub contribution: quantifying sustainability and resilience performance Sustainable infrastructure achieved by: Increasing performance Design process Analyze and balance trade-offs Reducing environmental impacts Reducing cost LCA LCCA Slide 23

24 More information available at:

25 Back-up Slides Slide 25

26 Present Value Present Value Cost Cost representations across life cycle Initial cost Energy Improvement Maintenance Hazard damage Year Discounted to Present Value Present Value of Cumulative Expected Cost Year Slide 26

Case study: Single family wood frame CUREE-Caltech Woodframe Project Two level of resistance: Minimum code compliant Enhanced Seismic enhancements: reduce nailing spacing in the shear

27 Case study: Single family wood frame CUREE-Caltech Woodframe Project Two level of resistance: Minimum code compliant Enhanced Seismic enhancements: reduce nailing spacing in the shear walls Hurricane enhancements: Increasing the resistance of roof shingle Stronger nails for roof panels Annealed glass thickens Stronger hurricane clip for roof to wall connection Slide 27

28 Present Value Thousands How to calculate Break Even Mitigation Percent $300 $250 Mitigation cost 14.3% on top of Initial A $200 $150 $100 $50 $0 20% of Initial A Design A Initial Hazard Design B 5% of Initial B Slide 28

29 FEMA Benefit Cost Analysis tool Slide 29

30 Compare life-cycle cost of hazards Slide 30

31 Embedded FEMA buildings types Manufactured home Wood & masonry single family Wood, masonry, concrete multi-family Engineered / non-engineered Strip mall Industrial/warehouse/factory Commercial Slide 31

32 Hurricane mitigation examples Shutters Roof: Type: Gable vs Hip vs Flat Cover: Built-up vs EPDM Roof-wall connection: Toe-nail vs strap Spacing of nails in roof-deck attachment Masonry reinforced Window area (Low, Med, High) Slide 32

The importance of a life cycle perspective in designing pavements and buildings

The importance of a life cycle perspective in designing pavements and buildings Jeremy Gregory Cement Sustainability Initiative Forum October 1-2, 2013 Vancouver, Canada Life cycle thinking is important