Learn About Housewrap Benefits to Improve Energy Efficiency and Home Comfort
For reducing home energy consumption and improving the indoor environment, housewrap is a product of choice for many homeowners. Housewrap is a lightweight, synthetic material installed to protect homes and commercial buildings against air leaks, water and moisture infiltration.
Thin but resilient, housewrap is weather-resistant but allows water vapor to pass from the inside to the exterior, helping prevent mold formation and rot. It overcomes the tiny gaps and cracks found in siding joints, providing a barrier to air and water that increases a home’s energy efficiency and comfort.
Modern housewrap materials offer many attractive features for homeowners and builders. Introduced in 1979 as spun-bonded polyolefin sheet, housewraps today also include woven and nonwoven polypropylene or polyethylene films. They provide enhanced resistance to damage during installation and superior air- and moisture-blocking performance. Synthetic housewraps feature microscopic pores, which allow water vapor to exit from the home interior but are too small to permit water and wind to enter.
When installed and sealed correctly, synthetic housewrap provides the following benefits:
- Minimizes wind and air leaks that create hot or cold zones in living areas;
- Minimizes water and moisture infiltration;
- Is vapor-transmissible, reducing the potential for condensation and thereby decreasing risk of mold growth and wood rot;
- Remains flexible at low temperatures;
- Increases total insulation R-value;
- Improves the efficiency of HVAC systems, considerably lowering total energy needs, and improving year-round comfort.
Housewrap and Siding
Housewraps are especially effective when installed in traditional, stick-built and/or wood-sided homes, as these structures have many seam gaps from overlapping materials. Vinyl- or aluminum-sided homes are also strong candidates, as their siding joints also have tiny cracks that allow wind and moisture to enter. Masonry-based sidings like brick and stucco also benefit from housewrap, though installers need to ensure they install a product designed to work effectively with these exteriors.
Many new homes are built with rigid-foam board insulation composed of polyurethane, polystyrene, or polyiso sheets. Housewrap will further increase the high efficiency of foam-board insulation. Housewrap material usually is installed beneath rigid-foam insulation sheets, not around them, though contractors often make the final decision on-site depending on specific construction details. Combining the two will further enhance your home’s insulation against external wind and moisture.
Tips for Proper Housewrap Installation
Though sometimes retrofitted on existing buildings, housewrap is typically installed on new homes or additions, before doors and windows go in so these important openings can be carefully sealed. As a weather-resistive barrier (WRB) type, housewrap is addressed in relevant local building-code sections, so a professional contractor can ensure your installation meets code requirements. Manufacturers provide specific instructions regarding minimum horizontal and vertical overlaps, as well as the placement of plastic- or metal-cap fasteners that protect the wrap from damage.
Housewrap installation incorporates typical WRB best practices although adjustments may be required in specific circumstances. The material is wrapped horizontally around the house, starting at the bottom of the wall. Each subsequent layer is lapped over the previous layer, shingle-fashion, to allow any condensed water to drain down the exterior surface. Manufacturers often recommend taping each layer to increase durability during installation. To maximize its air-barrier efficiency, layers are taped and sealed; window and door edges are wrapped; and, moisture drainage should be provided for at the bottom of the external siding.
Housewrap Market Growth
Housewrap benefits are obvious to homebuilders as well as homeowners. As a result, the housewrap market continues to expand for both new-construction, addition, and renovation applications. Despite the COVID-19 crisis, 360marketupdates.com projects the worldwide housewrap market will grow from 2020 through 2026 at a compounded annual growth rate of 4.4% to a projected US$2.4 Billion. Notable manufacturers include Dow, DuPont, Fiberweb, James Hardie, and Owens Corning.
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