How to Apply Felt or Building Paper
Protect new construction with building paper and roofing felt. We'll help you choose the right product for your area and show how to apply it to your home.
Building paper, also called house wrap, is a strong, fibrous paper that blocks water and moisture from entering from the outside but allows moist air to pass through from the inside, preventing a buildup of moisture inside walls that can lead to mold.
It's important that use the building paper that is recommended for your area. Many builders use standard 15-pound roofing felt. Felt labeled "ASTM 15" meets specific standards and is the norm in many areas.
Felt or building paper must be applied to walls properly to be effective. Install pieces in the correct order and make cuts carefully, so any moisture can travel downward at all points without slipping under the wrap. Install flashings (metal, self-adhesive, or both) as recommended by the window or door manufacturer or as required by local codes. Pull the wrap tight when you install it to prevent creases that could lead to slight waves in the siding.
Working with one or two helpers, expect to spend half a day applying 1,600 square feet or so of building wrap. It will take more time if extensive flashings are required. Before you begin, remove any old siding, nails, and building wrap from the sheathing.