Focus on Energy: Housewrap and Air Leakage New Studies

If you read advertising, you may get the idea that a housewrap is all you need to protect a building from air leaks. Building scientists, on the other hand, have always been skeptical of the product's effectiveness as an air barrier. Unfortunately, both sides have been hampered by the fact that the energy-savings benefits of housewrap have never been accurately quantified. DuPont tried to remedy the situation by sponsoring two research projects that aimed to nail down the value of its Tyvek brand and a half-dozen similar products. While the results indicate that a properly installed housewrap can bring real energy benefits, they also confirm most building scientists' commonsense evaluations (Focus on Energy, 10/91). Field Tests The first DuPont project involved a group of