What Is House Wrap, and What Is It Used For?

By: ROS Team

Imagine a silent guardian, protecting your home from the elements, unseen yet vital. That’s the role of housewrap, a thin but powerful barrier hidden behind your siding. It shields your walls from rain, wind, and moisture, preventing rot, mold, and energy loss. But what exactly is homewrap, and why is it so crucial for your home’s health and longevity?

What is House Wrap?

House wrap is a synthetic material used to protect buildings from moisture and air infiltration while allowing water vapor to escape. It is typically installed beneath the exterior siding of a structure and acts as a weather-resistant barrier, improving the building’s energy efficiency and preventing mold growth and water damage.

Commonly made from materials like polyethylene or polypropylene, house wrap helps maintain a home’s structural integrity and indoor comfort.

What is House Wrap Used For?

The primary function of house wrap is to safeguard your home’s exterior. It acts as an extra layer, guarding against water and air seeping inside. The wrap sits behind the exterior siding, forming a shield. While keeping moisture out, it still lets water vapor exit. This helps avoid mold, rot, and damage to the wood frame and insulation.

Types of House Wrap

1) Asphalt Felt

The traditional house wrap, asphalt felt is a paper-like material impregnated with asphalt for water resistance. It’s inexpensive and readily available but offers less breathability and durability compared to other options. It’s primarily used under shingles and not recommended as the main house wrap.

2) Polyolefin Fabric

This is the most common type of modern house wrap, made from woven or non-woven polypropylene or polyethylene fibers. It’s lightweight, water-resistant, and highly breathable, allowing moisture vapor to escape while preventing bulk water intrusion. Polyolefin fabric comes in various forms, including micro-perforated versions for enhanced breathability.

3) Liquid-Applied House Wrap

This alternative to traditional sheet house wrap is a liquid or spray-on application that forms a water-resistant barrier directly on the sheathing. It offers seamless coverage and can be ideal for complex wall shapes, but requires specific application techniques and may have higher cost compared to sheet options.

4) Rigid Foam

While not a true house wrap, rigid foam insulation panels like XPS or EPS can also function as a water-resistant barrier when properly sealed. They offer additional benefits of thermal insulation, but require careful installation and detailing to ensure watertightness.

What You’ll Need to Install House Wrap?

To install house wrap, you’ll need:

Essential Materials:

Housewrap: Choose the type suitable for your climate and cladding.
Fasteners: Use cap nails or cap staples specifically designed for housewrap.
Tape: Housewrap tape for sealing seams and penetrations.
Utility Knife: For cutting the housewrap.

Additional Tools:

Hammer tacker
Utility knife
Ladder
Safety glasses
Gloves

How to Install House Wrap?

Installing house wrap involves several key steps:

Preparation:

Ensure your exterior sheathing is dry and free of debris.
Apply primer to wood sheathing if required by the siding you’ll be using.

Starting at the Bottom:

Unroll the house wrap horizontally at the bottom of the wall, starting at one corner.
Overlap the bottom edge of the house wrap onto the foundation by 2-4 inches.
Secure the house wrap with cap nails or staples every 12-18 inches.

Overlapping and Shingling:

Continue rolling the house wrap upwards, overlapping the horizontal joints by at least 6 inches and the vertical joints by 12 inches.
Ensure the overlaps are shingled, with the upper layer overlapping the lower.

Window and Door Openings:

For openings, roll the house wrap over them temporarily.
Cut out the openings later, making Y-shaped cuts at the corners.
Wrap the flaps of the house wrap inside the rough opening and secure them with tape.

Sealing Seams and Penetrations:

Use housewrap tape to seal all horizontal and vertical seams, as well as around penetrations like pipes and vents.
Ensure the tape is properly adhered to create a watertight barrier.

Finishing Touches:

Trim any excess house wrap at the top of the wall.
Install flashing tape around specific areas like chimneys and rooflines for added protection.

Is House Wrap Waterproof?

House wrap is a protective material that helps keep water out, but it’s not totally waterproof. House wrap does a great job resisting water, but it’s not designed to be a standalone barrier against prolonged water exposure. The main purpose of house wrap is to let moisture vapor escape from the walls. This prevents moisture buildup inside the walls, which can cause rotting and mold growth.

What Is Home Wrap Cost?

The cost of house wrap material differs based on the type and brand. It generally falls between $0.30 and $1.50 per square foot. However, the full cost incorporates labor fees for installation, significantly hiking the total price. You can expect an overall average cost of $0.52 to $0.63 per square foot when hiring professionals for installation.

Do I Need House Wrap?

House wrap is a material used to shield your home from water and air infiltration. It acts as a barrier, preventing moisture and drafts from seeping through the walls. Although house wrap installation is not a legal requirement, construction experts strongly advise using it.