House Wrap Under Roof Sheathing

I ve been using hardie siding in the texas heat for over 10 years.

House wrap under roof sheathing.

The primary goal of a sheathing wrap or housewrap is to protect a building s structural components from water. Hardiewrap weather barrier is installed over the sheathing beneath the exterior siding to reduce water and air infiltration. In general a sheathing wrap should have a perm rating of at least 5 to enable walls to dry out in a reasonable period of time should they get wet. It just a matter of careful detailing especially around doors windows and other joints prone to leakage.

The homes i built then still look brand new today. Plastic housewraps range from around 5 to over 50 perms. In this post we compared barricade wrap plus tyvek homewrap homeguard house wrap certainteed certawrap and the zip system. The other wrinkle is that when using zip sheathing very few manufactures include instructions for installation on that type of sheathing.

Work from the bottom up overlapping the lower courses. Traditional sheathing wraps such as asphalt felt and grade d building paper used under stucco both measure about 5 perms. For instance protecto wrap flashing tape on tyvek. The reason for this is the housewrap manufacterers instructions call out their own product not their competitors.

Wrap the fabric around the edges of windows. In theory the sheathing on your home should never get wet as long as the proper preparations are made when siding the home flashing house wrap j channel caulk etc. At the same time the sheathing wrap must be permeable enough to allow drying to the building s exterior if the framing or sheathing should get wet. Depending on how it s hung house wrap can either act as a moisture or wind barrier.

General recommendations that usually apply to fabric type house wrap include. Most house wraps are weather resistant barriers wrbs that aim to prevent air and moisture infiltration to the wall system while protecting the sheathing. Install house wrap before doors and windows. When used to slow winds its job is to seal gaps and leaks in the osb panels or plywood sheathing that makes up your home s exterior walls.

It is literally wrapped around a building cut out around windows and doors and taped at the seams. House wrap behind a building s siding is an excellent secondary defense against the weather. House wrap is a weatherization membrane which provides a protective layer under a building s siding and over the wall girts or sheathing. You can find a complete library of technical documents for the zip system at this link.

Seal all seams with a special tape provided by the house wrap manufacturer.