Tips for Selecting a High-Performance Housewrap
Tip #1: Don’t mix water with wood. Tip #2: Don’t let damp wood stay wet. Intuitive? Of course it is. Wet wood rots. Yet, this is a lesson the building industry has had to learn the hard way – and more than once – since necessarily stringent building codes have gone into effect in recent years. The well-intended codes are our industry’s effort to create airtight buildings. Good news for energy consumption but bad news for damp walls.
Fortunately, building science has taught industry professionals a thing or two about the movement of air and moisture in and around the building envelope. We can now create airtight buildings that also fend off unwanted, unavoidable moisture that originates both inside and outside of a building.
Use of housewrap is no doubt a best practice in builders’ efforts toward airtight construction. There is a high demand for housewrap and as a result, there are several products on the market. How do you know which one performs the best? Before buying one brand over another, ask these five questions to make sure you’re selecting the highest performing housewrap.
Is the housewrap durable?
It’s an obvious question, but an important one. A durable housewrap is one that stays in place, has exceptional tear strength, and can stand up to surfactants and UV rays.
Avoid common jobsite do-overs by opting for a high-performance material that has exceptional tear resistance and is designed to withstand heavy winds and jobsite rigors. Additionally, housewraps with superior surfactant resistance will minimize water penetration and the resulting component degradation. Finally, it is best to work with a high-performance material that incorporates UV inhibitors into its coating and fibers, preventing deterioration that can occur from UV exposure.
Does the housewrap breathe?
A building wrap must breathe to prevent moisture vapor from getting trapped in the wall cavity. Builders should work with high-tech housewraps that can balance water holdout with an optimal perm rating of 10 to 20 perms. This perm rating ensures that while water is prevented from entering the wall cavity, ideal levels of moisture vapor are allowed to escape.
Can the housewrap serve as an effective air barrier?
should. It is not too lofty a goal to expect a housewrap to perform as
an air barrier that helps reduce air infiltration. High-performance
housewraps serve as effective air barriers by reducing convective wind
washing against sheathings and air infiltration into stud wall cavities.
When installed as part of an air barrier assembly, a housewrap has the
ability to reduce drafts in homes, increase indoor comfort, and decrease
energy use by reducing the amount of non-conditioned air that enters
and exits conditioned wall cavities.
Does the housewrap come with a system warranty?
good warranty speaks volumes about the quality of a product. Some
high-performance housewraps on the market back builders with excellent
warranties on labor and materials. Be sure to choose a housewrap that
Is the housewrap part of a holistic system?
Housewraps do not operate in a vacuum. They are part of a holistic approach to airtight construction, or at least they should be. As such, they require thorough, comprehensive integration with other elements of the building envelope in order to retain system integrity. In other words, be sure the housewrap includes compatible tapes for seaming and adhesive flashings for openings as these details vastly improve the air and moisture resistance of the housewrap.
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