The science behind our work

Studies show radiant barriers can reduce cooling costs 5% to 10% in a warm, sunny climate, and work best where ducts run through the attic.

A radiant barrier cuts heat flow from the attic into the house by about 40%, and aluminum foil blocks about 95% of the heat radiated down by the roof.

Consumer fact sheet on attic radiant barriers, prepared by Oak Ridge National Laboratory for the Department of Energy.

Laboratory testing of attic radiant barrier systems in a large-scale climate simulator.

Insulation resists heat flow and lowers heating and cooling costs. Includes recommended R-values by climate zone.

ENERGY STAR step-by-step guide to adding attic insulation, including fiberglass batts and blown-in loose fill.

EPA estimates homeowners save an average of 15% on heating and cooling costs, or 11% on total energy costs, by air sealing and adding insulation.

In a typical house, about 20 to 30 percent of the air that moves through the duct system is lost to leaks, holes and poorly connected ducts.

Ducts that leak heated or cooled air into unconditioned spaces can add hundreds of dollars a year to heating and cooling bills; ducts should be well sealed.

Recommends expanding foam or caulk to seal openings around plumbing vent pipes and electrical wires in the attic.

ENERGY STAR guide to sealing attic air leaks, including using spray foam to seal gaps and open cavities.

DOE Building America guidelines for finding and sealing attic air leaks.