ETL 11-8 Decision Criteria for Installing Vegetative Green Roofs at CONUS Installations  


This ETL provides guidance for determining if installing a vegetative roof on a CONUS Air Force facility is suitable. The intent is to give the base a simple tool to justify selection or non-selection of a green roof based entirely on return on investment (ROI). Selection of a vegetative green roof for environmental or social reasons can certainly be valid but is not part of this ETL’s selection criteria. Vital to the ROI are the facility characteristics, occupancy type, and the local climate. This ETL lists benefits of a vegetative roof, provides initial cost and ROI prediction, and provides general maintenance requirements associated with the waterproofing and green components of this roofing system. For more details on the different types of green roofs—and the advantages and disadvantages of each—consult the Peterson AFB study referenced in paragraph 3.1.