1. 2011 GreenGov Symposium Oct. 31 - Nov. 2, 2011 Washington Hilton  Washington, DC Green Facilities – Session 2 Economic Value of Green Facilities October 31, 2011 Green Roofs: Benefits, Costs, Challenges & Opportunities Ken Sandler Sustainability and Green Building Advisor US General Services Administration Presentation Title

2. Green Facilities – Session 2 Economic Value of Green Facilities October 31, 2011 Green Roofs: Benefits, Costs, Challenges & Opportunities US Census Bureau Headquarters, Suitland, MD

3. Green Facilities – Session 2 Economic Value of Green Facilities October 31, 2011 What You’ll Hear From Me  GSA’s Green Roof Study Why we conducted it Our goals and methodology  Findings Benefits – environmental, economic, social Cost-benefit analysis So what’s the bottom line?

4. Green Facilities – Session 2 Economic Value of Green Facilities October 31, 2011 GSA’s Green Roof Study NOAA Operations Center, Suitland, MD

5. Green Facilities – Session 2 Economic Value of Green Facilities October 31, 2011 GSA’s Green Roof Study  Mandated by Congress  Great opportunity to examine a technology GSA has embraced Almost 1 million square feet of green roofs in our inventory  Targeted at decision makers  Disclaimer: all conclusions preliminary until report released

6. Green Facilities – Session 2 Economic Value of Green Facilities October 31, 2011Approach  Literature review of 200 reports, case studies & research papers, plus interviews w/experts  Broad focus on green roofs on commercial and public buildings  Analysis of benefits  Cost benefit analysis, for US and Washington, DC region  Challenges & best practices to maximize benefits  Research and data needs

7. Green Facilities – Session 2 Economic Value of Green Facilities October 31, 2011 Benefits of Green Roofs EPA Region 8, Denver, CO

8. Green Facilities – Session 2 Economic Value of Green Facilities October 31, 2011 Benefits Analyzed  Stormwater runoff  Urban heat island effect and energy savings  Biodiversity and habitat  Air quality  Acoustics and quality of life  Jobs and urban agriculture  Roof longevity

9. Green Facilities – Session 2 Economic Value of Green Facilities October 31, 2011 Stormwater Runoff  Green roofs have been shown to: Reduce stormwater volume and flow – Capture and retain first ½ - ¾ inch of rainfall in a storm. – Retain from 38% - ~100% of precipitation. – Reduce rate of runoff from a roof by up to 65% – Add 3 hours to the time it takes runoff to leave a roof. Reduce stormwater pollutants – Neutralize acidity of acid rain – Reduce stormwater flow and volume, thereby reducing pollutants swept into water bodies – But impacts on nutrient pollutant reduction seem mixed

10. Green Facilities – Session 2 Economic Value of Green Facilities October 31, 2011 Urban Heat Island Reduction and Energy Savings  Green roofs have been shown to: Reduce the heat island effect: – Lower surface temperatures – Create a cooling effect Reduce building energy use: – Reduce buildings’ summer solar heat gain, by up to 84% – Reduce building energy use, especially in summer – Potentially reduce strain on HVAC systems

11. Green Facilities – Session 2 Economic Value of Green Facilities October 31, 2011 Biodiversity and Habitat  Green roofs have been shown to: Attract species, including spiders, birds, bees, butterflies, beetles, wasps – as well as plants Improve urban environmental effects that foster biodiversity: – Reduced stormwater runoff – Lowered heat island effect  And can be designed to attract specific species, with habitat, food and nesting areas aimed at them

12. Green Facilities – Session 2 Economic Value of Green Facilities October 31, 2011 Air quality and Greenhouse Gas Reduction  Air quality: Nitrogen-oxygen compounds and particulate matter = pollutants most likely to be removed In Washington DC, ~58 metric tons of air pollutants might be removed  Greenhouse gas reduction: Carbon expended to create and install a green roof typically higher than carbon it can absorb But when energy savings factored in, a green roof can be a net carbon sink

13. Green Facilities – Session 2 Economic Value of Green Facilities October 31, 2011 Acoustics and Quality of Life  Acoustics: Better at noise reduction than traditional and concrete roofs, per unit of weight Reduction on top floor of 8 decibels or more  Biophilia: Evidence that more exposure to greenery can increase occupant health and productivity

14. Green Facilities – Session 2 Economic Value of Green Facilities October 31, 2011 Job Creation and Urban Agriculture  Job creation: US green roof jobs rose > 80% from 2004 to 2005 German green roof industry growing 15% -20%/year since 1982  Urban agriculture – potential to: Reduce distance food travels to reach consumers, thereby reducing energy use & carbon emissions Provide fresh, local food options with less pesticides Help create jobs and increase property values

15. Green Facilities – Session 2 Economic Value of Green Facilities October 31, 2011 Roof Longevity  Results: Longevity estimated from 25-60 years – about double the lifespan of conventional roofs  How green roofs do it: Vegetation layer and growing medium protect the roofing membrane from damaging UV radiation and from fluctuations in temperature extremes

16. Green Facilities – Session 2 Economic Value of Green Facilities October 31, 2011 Green Roof Costs and Benefits 10 West Jackson, Chicago, Illinois

17. Green Facilities – Session 2 Economic Value of Green Facilities October 31, 2011 Green Roof Costs and Benefits  Added cost of installing a green roof is mostly made up for by its increased longevity  Added maintenance costs are significant  Key benefits to building owners = reduced stormwater and energy costs; real estate benefits (rent, value, etc.)  Key benefits to community = reduced infrastructure maintenance or replacement costs, improved aesthetics, biodiversity, job generation  Over 50-year period, stormwater, energy, carbon and community benefits of green roofs exceeded increased premium of installing, maintaining & replacing them

18. Green Facilities – Session 2 Economic Value of Green Facilities October 31, 2011Conclusions USDA Jamie L. Whitten Building, Washington, DC

19. Green Facilities – Session 2 Economic Value of Green Facilities October 31, 2011Conclusions  Significant benefits Especially stormwater, energy, heat islands, biodiversity  Added installation and maintenance costs can be offset by roof longevity and payback  Most challenges surmountable through best practices  Over the building lifecycle, return on investment plus community benefits generally justifies the added costs

20. Green Facilities – Session 2 Economic Value of Green Facilities October 31, 2011 Thanks for your time Ken Sandler GSA Office of Federal High Performance Green Buildings ken.sandler@gsa.gov 202-219-1121