LEED is the only nationally recognized green building rating system and evaluates the performance of buildings from a “whole building” perspective. It provides project developers a checklist of criteria by which a building can be judged in six categories, including Sustainable Sites, Water Efficiency, Energy & Atmosphere, Materials & Resources, Indoor Environmental Quality, and Innovation & Design.

The largest point-generating category is Energy & Atmosphere. There are four possible ratings: LEED Certified, Silver, Gold and Platinum. A gold-rated building is estimated to have reduced its environmental impact by 50% compared with an equivalent conventional building.