In 2007, Oak Ridge built a roof with phase-change material between foil layers; attic temperatures fell about 22°F, with utility savings estimated at 8%

Developed by Oak Ridge National Laboratory, innovative attic technology utilizing phase change materials has proven to lower attic temperatures and reduce cooling energy use significantly. Research conducted almost twenty years ago highlighted its potential for residential applications, and follow-up studies confirmed its passive cooling benefits. Despite its effectiveness, this groundbreaking technology has yet to see widespread acceptance in the market.