STYROFOAM™ WEATHERMATE™ Plus Installation Guide – New Construction (254KB PDF)
When installing housewrap, you want to achieve a continuous membrane that resists air and water penetration into the structure. The correct installation of STYROFOAM WEATHERMATE Plus housewrap is a simple, fast process.
1. STYROFOAM WEATHERMATE Plus housewrap should be installed over exterior wall sheathing before windows are installed.
Figure 1
2. Place roll vertically against exterior wall about 3 feet from corner with print side facing out. Small diamond markers are printed every 8 inches on STYROFOAM WEATHERMATE Plus housewrap to help determine position of underlying studs. Position bottom edge of housewrap to cover edge of sill plate and overlap foundation at least 1 inch. Position top edge of housewrap to cover edges of top plates.
Figure 2
3. With roll straight and plumb, attach trailing end of housewrap to framing members or nail-base sheathing. Unroll around corner, keeping membrane level, tight and flat. Wrap completely around building, covering windows and doors. Tuck tightly into inside corners using flat edge of 1x4 or similar.
Figure 3
4. Overlap all vertical seams at least 6 inches and seal with tape. Overlap all horizontal seams at least 6 inches shingle fashion and seal with tape (the higher piece on the wall should lap over the lower piece). Acceptable tapes include WEATHERMATE™ Construction Tape, Tyvek tape or equal. Ensure tape is properly applied to seams to ensure a weather-tight bond.
Figure 4
5. Plastic cap nails are appropriate fasteners for STYROFOAM WEATHERMATE Plus housewrap. There are pneumatic nailers for plastic cap nails that make fastening fast and secure. Plastic cap nails should be spaced about 16 inches in each direction. Staples with minimum 1-inch crown may also be used when spaced about 12 inches in each direction. All fasteners should penetrate at least 1/2 inch into nail base.
Figure 5
6. At each window and door rough opening, make an inverted "Y" cut in the STYROFOAM WEATHERMATE Plus housewrap:
- Cut from the top center of the opening straight down about half the height of the opening.
- From this point at the center of the opening, make a cut diagonally to the lower right corner of the opening and a second cut to the lower left corner.
- Finish by cutting completely across the upper edge of the opening
- Pull each of the three flaps to the inside of the opening and fasten to the inside face of the framing with staples spaced every 6 inches. Trim excess.
Figure 6
7. Install windows and doors according to manufacturer's recommendations. Flash windows and doors according to building code requirements. When flashing windows, doors, roofs, deck connections to walls, etc., be careful to lap housewrap and flashings so water does not get behind flashing.
Figure 7
8. STYROFOAM WEATHERMATE Plus housewrap should not be exposed to sunlight for more than 120 days. Before installing exterior finish, be sure all penetrations are taped to shed water and prevent air infiltration.
Figure 8
9. Although Dow does not require an air space between STYROFOAM WEATHERMATE Plus housewrap and exterior finishes, good building practices and some building codes specify air spaces behind brick, stone and wood finishes.
Note: STYROFOAM WEATHERMATE Plus housewrap is a secondary defense against bulk water intrusion. The exterior finish is the primary water barrier. Wall assemblies are best protected from water intrusion by installing the exterior veneer over water repellent sheathing or installing the exterior veneer over a weather-resistive membrane which is installed over exterior sheathing. If STYROFOAM WEATHERMATE Plus is installed directly over studs with no sheathing, the exterior veneer must be carefully chosen and installed to provide maximum protection against water intrusion.
