The U.S. Green Building Council is working to modify its LEED certification to increase energy-efficiency requirements, as well as put a premium on low-footprint materials through a points-based credit system. Some of the "easier strategies" that helped builders achieve LEED certification will be changed. "It's going to require a much more nuanced, sophisticated measure in a whole bunch of different ways of the actual environmental performance of the building," said Nadav Malin, president of BuildingGreen.