This calculator was developed through a collaboration involving researchers and staff at Portland State University, University of Toronto, and Green Roofs for Healthy Cities. The effort was funded by the US Green Building Council with additional financial and in-kind support from University of Toronto, Portland State University, GRHC, and Environment Canada.
The green roof energy calculator allows you to compare the annual energy performance of a building with a vegetative green roof to the same building with either a dark roof or a white roof . At the present time simulations are available for new construction (ASHRAE 90.1-2004) and old construction (pre-ASHRAE 90.1-2004) office and residential buildings driven by typical precipitation and weather data. Representation of an irrigation schedule is optional. Read more about how the Calculator works.