Until now, much of the market for residential duct sealants has been largely limited to a few southern states such as Florida, where cooling air is at a premium and energy consumption is high. However, many industry officials say that no matter where a home is located or how well its ductwork is made, up to 15% of the cfm will escape through seams, joints and other penetrations.

That fact combined with a major push by the U.S. Department of Energy has the market for sealants such as United McGill AirSeal's Uni-Mastic 181 on the rise. Because duct sealants help prevent the escape of air into walls, basements, attics and other areas where it is not wanted, the average homeowner can realize a substantial savings on energy bills if the contractor applies a duct sealant, said Scott Witherow, a manager with United McGill AirSeal in Columbus, Ohio.

Duct sealants are typically applied with a brush, over all slip and drive connections, seams and all other fittings in the hvac system. In the past, most of the ductwork on many new home constructions was not sealed or products not ideally suited to the task, such as duct tape, were used. But that's now changing, Witherow said.

"People are starting to (use sealants) more and more," he said. "I would estimate that within 10 years, every new house will have the ducts sealed." Some banks are offering better interest rates for mortgages on homes deemed energy efficient and Witherow predicts that will help increase use of the product.