New Heat Mitigation and Water Retention Concepts to Expand Green Roofing Demand Greening Rooftops for Sustainable Communities June 4, 2009 Atlanta, GA James L. Hoff, DBA Research Director

2 2 A New-Old Concept Ballasted Roofs

3 3 Simple

4 4 Ballasted Roofs Economical

5 5 Ballasted Roofs Protection Albo Corporation, West Bend, WI Ballasted Roof Installed in 1980

6 6 1 Windrow & Sweep 2 Cut & Stack 3 Chop 4 GrindSieve & Package 5 Recycle 6 Ballasted Roofs Easily Recycled Source: EPDM Roofing Association

7 7 Ballasted Roofs Historic Benefits Economical Durable Recyclable Low Initial Cost Low Life Cycle Cost Low Environmental Impact

8 8 Ballasted Roofs Emerging Benefits Heat Island Mitigation Storm Water Retention

9 9 Envelop Systems Research Apparatus Oak Ridge National Laboratories Ballasted Roofs Heat Island Mitigation

10 Hour OFOF Black EPDM Light Ballast (10#) Med. Ballast (17#) Heavy Ballast (21#) White TPO Concrete Paver Painted Paver 1 Painted Paver 2 Ballasted Roofs Heat Island Mitigation Average Roof Membrane Temperature By Hour Source: Desjarlais, Petrie & Atchley, 2008

11 Black EPDM Light Ballast (10#) Med. Ballast (17#) Heavy Ballast (21#) White TPO Concrete Paver Painted Paver 1 Painted Paver 2 Hour BTU / (H X Sq. Ft.) Ballasted Roofs Heat Island Mitigation Average Heat Flux By Hour Source: Desjarlais, Petrie & Atchley, 2008

12 California Title 24 (Min. 21 # / sq. ft.) Chicago Energy Code (Min. 15# / sq. ft.) Ballasted Roofs Heat Island Mitigation Now Recognized By…

13 Ballasted Roofs Storm Water Retention Source: Carlisle Construction ProductsSource: GreenGrid ® EcoBallast ® Systems Retention Mat Option Interlocking Tray Option

14 Ballasted Water- Retaining Roof Extensive Green Roof Smooth Stone Ballast (2” to 4”) Planting Medium ( 2” to 6”) Moisture- Retention Mats (1 or 2) Moisture- Retention Mats (1 or 2) Drainage Board Protection Mat Roof Membrane Roof Insulation Roof Deck Drainage Board Protection Mat Roof Membrane Roof Insulation Roof Deck Storm Water Retention Retention Mat Option

15 Modular Ballasted Water-Retaining Roof Modular Extensive Green Roof Smooth Stone Ballast (2” to 4”) Planting Medium ( 2” to 6”) Protection Mat Roof Membrane Roof Insulation Roof Deck Protection Mat Roof Membrane Roof Insulation Roof Deck Interlocking Tray Storm Water Retention Interlocking Tray Option

16 Ballasted Roofs Water Retention Testing Water Retention Test Apparatus Architectural Testing, Inc. York, PA

17 Rain Event 1” / Hour 2” / Hour 4” / Hour Single Retention Mat 22.4% 6.2% 5.9% Double Retention Mat 37.8% 11.5% 5.6% Percent Water Retention: Three Hours After Simulated Rain Event Ballasted Roofs Water Retention Testing Source: Architectural Testing, Inc., 2008

18 The Opportunity Integrating Green & Ballasted Roofs Installed Cost ($US / Sq. Ft.) Annual Sales (Millions of Sq. Ft.) Green RoofBallasted Roof

19 The Future Hybrid Green / Ballasted Roofs Ballasted Areas Retain Storm Water Reduce Summer Temperatures and Add Wind, Fire & Traffic Resistance Vegetated Areas Reduce Summer Temperatures and Retain, Transpire and Cleanse Storm Water Tapered Roof Design Directs Storm Water

20 Hybrid Green / Ballasted Roofs Future Research Green / ballasted storm water testing and modeling Hybrid systems energy modeling Economic analysis to optimize benefit / return

21 New Heat Mitigation and Water Retention Concepts to Expand Green Roofing Demand Greening Rooftops for Sustainable Communities June 4, 2009 Atlanta, GA James L. Hoff, DBA Research Director