Water can be a home's worst enemy because it inevitably will find its way into walls. Tyvek® is a secondary water barrier behind siding that protects the wood structure of a home. When water gets inside walls, it can cause mold, mildew, even wood rot. Tyvek® under the siding is like adding a security blanket to a home. A home stays drier. Families STAY more comfortable.

When moisture vapor gets into walls, it needs a pathway to the outside. While Tyvek® is specially designed to keep rain and bulk water out, it also lets trapped moisture vapor escape. Walls stay dry inside, PREVENTING moisture buildup and potential structural damage.
Moisture is produced by many inside sources-cooking, appliances, even people and plants. Tyvek® lets moisture vapor escape, helping to prevent build-up. Tyvek® has SUPERIOR moisture vapor transmission.