Focus on Energy: Is Housewrap A Good Investment?

Once upon a time, a long time ago, a team of Dupont thinktankers pondered new uses for their spun-bonded sheet plastic known as Tyvek. Developed in the 1950s and first used as a bottom covering to hold the springs in furniture, Tyvek's greatest success at that time had been in envelopes, especially for overnight couriers like Federal Express. In its quest for new markets, Dupont began to explore other applications for Tyvek. What else would it be good for? Why not use it to wrap houses? Since, unlike other sheet materials used in construction, Tyvek is permeable to water vapor, it would allow walls to "breathe" moisture while controlling air leakage. The idea seemed golden. And it was. Tyvek brand housewrap dominated the