What is house wrap?

House wrap is a lightweight synthetic barrier installed directly over the exterior wall sheathing, typically as part of siding installation and replacement work. Its primary function is to shed liquid water that penetrates past the siding itself while remaining permeable to water vapor escaping from inside the home.

The material works in two directions. Externally, it blocks bulk water from rain, driven spray, and condensation from reaching the wood framing and insulation behind it. Internally, it allows moisture vapor generated in the house to migrate outward, reducing the risk of rot, mold, and structural damage. This vapor-permeable design distinguishes house wrap from older plastic sheeting, which traps moisture and can cause hidden decay.

Common brands include Tyvek, Housewrap, and similar brands manufactured by major building products companies. These wraps are typically white or translucent, lightweight enough to handle from a ladder, and perforated or textured to help water drain downward. Installation involves stapling or taping the material over the sheathing before siding goes up, with overlaps at seams running vertically to shed water downward.

Lake County contractors working in Florida's humid subtropical climate recognize house wrap as a standard defensive layer in siding systems. The combination of seasonal rainfall, salt spray in coastal areas, and high humidity makes a functioning weather barrier critical to preventing costly interior damage.