Housewrap — Wall Weather Barrier Home Guidebook Tips

A housewrap is a weather-resistant barrier installed over wall sheathing and under siding to resist water and uncontrolled air movement.

Housewrap diagram — labeled parts, dimensions, and installation context

What It Is

Housewrap is part of the wall's drainage and air-control layer. It is installed on the exterior side of the sheathing, lapped and taped so bulk water sheds downward while water vapor can still escape through the material. Its job is not to replace flashing or siding. Instead, it works with those components to keep wind-driven rain out of the wall assembly and reduce drafts.

Types

Common types include mechanically fastened wrap, self-adhered wrap membranes, and proprietary weather-resistant barriers integrated with drainage textures or seam tapes.

Where It Is Used

Housewrap is used behind vinyl, fiber cement, wood, metal, and many other siding systems on framed walls. It is typically visible during construction before the cladding is installed.

How to Identify One

You can identify housewrap during construction as the sheet material covering the sheathing and window openings. Tears, reversed laps, untaped seams, and poor flashing integration are the most common defects.

Replacement

Replacement is usually part of a re-siding project because the wrap sits behind the cladding. Small damaged areas can sometimes be repaired with compatible tape or patch material, but larger failures usually require siding removal.

Housewrap — FAQ

What does housewrap do?

It helps keep liquid water and outside air from getting into the wall assembly while still allowing trapped vapor to dry outward. That reduces the risk of rot, mold, and energy loss.

Is housewrap waterproof?

It is water resistant, not a substitute for full waterproofing. It is designed to shed incidental water behind siding, but it still relies on correct laps, flashing, and drainage details.

Can a house have siding without housewrap?

Some older homes do, especially if they were built before modern WRB requirements became common. Newer construction typically uses housewrap or another weather-resistant barrier behind the cladding.

Can torn housewrap be repaired?

Small tears often can be patched with the manufacturer's compatible tape or membrane. If damage is widespread or the flashing details are wrong, a bigger repair may be needed during siding work.

Is housewrap the same as a vapor barrier?

No. Housewrap is mainly an air and water-resistive layer, and it is usually vapor permeable by design. A vapor barrier or vapor retarder has a different moisture-control role.