Green Roof Design Tool


Dr. Roger Babcock, Water Resources Research Center/Civil Engineering, University of Hawaii at Manoa, and Yanling Li, Water Resources Engineer with Parsons Brinkerhoff, Baltimore, MD.

According to the USEPA*:

"One of the most interesting stormwater control systems under evaluation by EPA are “green roofs”. Green roofs are vegetative covers applied to building roofs to slow, or totally absorb, rainfall runoff during storms. While the concept of over-planted roofs is very ancient, the goals of modern green roof technology are to replace the benefits of vegetative cover on land which are lost when a building is erected. Research into this approach has been growing steadily since the 1980s, especially in Europe."


We created this program to calculate the single-event, hydrologic performance of modular green roofs based upon physical design parameters, media properties, and rainfall properties.

Click HERE to fill out the information form and proceed to the download links for the Excel-based program and quick-start guide.

We hope that this tool will prove useful to you in your design work.