Siding — whether vinyl, wood, stucco, brick, or composite — does not completely prevent air and water penetration. Tyvek HomeWrap is a secondary defense to help manage a home's wall systems by serving as a protective layer under siding and over the sheathing. The Tyvek weatherization membrane wraps around a home over the wood or foam sheathing, cut out around windows and doors and then taped at the seams.
The unique, nonwoven-fiber structure resists air infiltration and water intrusion, yet the product is engineered to allow moisture vapor to diffuse through the sheet, helping prevent mold and mildew buildup and wood rot. While the microscopic pores of Tyvek's fibrous structure readily allow evaporation, these pores are so small that bulk water and air cannot penetrate. Circle
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In My Own Words"DuPont's Tyvek house wrap really seals up the house from the weather, preventing water intrusion, which is extremely important. It also allows the insulation to perform as designed. You may start with an R-13 insulation, but without a good house wrap, the insulation won't perform at R-13 on windy days. In fact, performance may drop to R-7 or less. Preventing water intrusion and maximizing the performance of the insulation are the main reasons we like Tyvek. Of course, most of our customers are familiar with Dupont Tyvek, and they see it as a quality product, so that helps, too."
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