What is Housewrap?  Why is Housewrap important?

Housewraps prevent water from entering the wall cavity while allowing moisture inside the wall cavity to escape.  Housewrap, also know as weather resistive barriers, is installed between the sheathing (OSB board) and the siding.  Housewrap is a breathable barrier that focuses on water resistance, vapor permeability, and air filtration. Some common housewraps are made from synthetic polypropylene.

Housewraps are the last line of defense against wind driven rain and solar driven moisture.  An important siding installation element that prevents water from entering the wall cavity, causing mold and rot leading to structural damage. 

Housewrap has to defend your home from exterior weather forces while being permeable enough to allow any liquid that gets through the sheathing from the inside of your home to evaporate to the exterior of your home. A high permeability number means more vapor will pass regardless of the direction through the material. Good housewraps have thousands of tiny perforations.  This allows the vapor produced to breathe – usually 10-20 perms are a good range.

Good building wraps have important benefits such as breathability, high tear strength, qualified air barrier properties, and surfactant resistance. There are even some that will help insulate your home (Blueskin VP100), and reduce energy costs, eliminate drafts, and have self sealing technology

Why is proper installation of housewraps important?
Why is using the correct fasteners important?

Fasteners puncture the membrane allowing for a potential leak. Therefore, nails and staples are not a good choice. Taping all seams and overlaps prevents heating and cooling loss. Correct installation techniques with special attention over and around windows and doors is a must.  

The proper installation around windows flashing is a common mishap. If your window is not flashed and sealed properly with Housewrap, moisture can be directed into the wall assembly causing problems.  This is where many window leaks come from – around penetrations through the housewrap. The same thing happens with doors. Proper installation is crucial.

Installing housewrap correctly is as important as having your siding installed correctly.  It provides drainability and drying of the wall assembly. It is not a detail that should be overlooked. At A. M. Burney Exteriors, Inc., our siding installers are trained to install housewraps correctly to ensure a properly functioning siding installation.  Call now to schedule free estimate. We service Minneapolis and St. Paul and eight county areas.