Three innovative insulation materials could soon be used for commercial building retrofits in the U.S. as costs of these products fall and local building codes allow their use, says Aditya Ranade, senior analyst with Lux Research and head of the firm's Sustainable Building Services. Vacuum insulation panels offer thermal efficiency while maximizing floor space; aerogels offer flexibility for interior and exterior use; and phase-change materials benefit buildings in areas with warm days and cold nights.