The Integration and Optimization of Sustainability Benefits from Shading-Type Green Roof Technology

EPA Grant Number: SU835074
Title: The Integration and Optimization of Sustainability Benefits from Shading-Type Green Roof Technology
Investigators: Loge, Frank , Holmes, Amelia , Hubert, George , Chacon, Kimberly
Current Investigators: Loge, Frank , German, Alea , Holmes, Amelia , Sherraden, Catherine , Chacon, Kimberly
Institution: University of California - Davis
EPA Project Officer: Hahn, Intaek
Phase: I
Project Period: August 15, 2011 through August 14, 2012
Project Amount: $11,162
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet (2011) RFA Text |  Recipients Lists
Research Category: Pollution Prevention/Sustainable Development , P3 Challenge Area - Sustainable and Healthy Communities , P3 Challenge Area - Air Quality , P3 Awards , Sustainable and Healthy Communities


The shading-type green roof integrates green roof cooling benefits with other sustainability parameters to optimize reduction in peak electricity demand for cooling by as much as 25%. System integration leverages non-potable water for toilets (26% of average household indoor use), evaporative cooling, and other landscape irrigation while rooftop irrigation provides structural fire protection. Green roof technology has been the subject of at least ten previously successful P3 projects. However, these projects have not quantified the cooling efficacy or examined the inherent ecological benefits of green roofs. Like a shade cloth canopy, a shading-type green roof reduces direct solar heat gain. Plant palette selection for maximum leaf area index maximizes shading capacity. A wastewater reclamation system eliminates potable water use for green roof irrigation and other household uses. Ecosystem services and agricultural value are obtained from a shading-type green roof when plant species are selected to enhance the foraging and nesting preferences of pollinators. A systems-based approach and lightweight construction offer a modular design suitable for retrofit applications.


Green roof technology improves environmental building control, offers aesthetic appeal (people), and reduces energy consumption (planet). Light-weight green roof systems carry lower capital cost (prosperity) and expand opportunities for retrofit (planet). Food sources for pollinators benefit the ecosystem (planet) and also support local agriculture (prosperity). Secondary uses for reclaimed water reduce potable water use (planet) and also decrease system amortization periods (prosperity). Fire protection addresses all three areas of sustainability (people, planet, prosperity). This project will partner with relevant product manufacturers and the University of California at Davis to educate a broad spectrum of professionals, trades people, students, and end users about this technology.

Expected Results:

(Phase 1) Design two to three residential and commercial retrofit systems; develop plant palettes that satisfy system requirements and support pollinators; demonstrate the value to investors with a comparative economic loading order analysis. (Phase 2) Install and monitor two to three residential and commercial retrofit systems; conduct educational outreach and demonstration tours; develop business partnerships and raise venture capital.

Supplemental Keywords:

green building, energy conservation, water conservation, pollination services, wildfire protection

Progress and Final Reports:

  • Final Report