Part 2: Install a Nail Fin Window Over Housewrap

Use a manufacturer-approved type of sealant to bond the window to the water-resistive barrier before setting, squaring, and fastening the window to the framing.

When installing a nail-fin window in a wall with housewrap, the process starts with shims under the window—in this case cut offs of bevel cedar siding. Besides creating a level surface, these shims support the jambs to prevent deflection, and also create a gap under the window, which aids in the drainage process should that ever become necessary. Care is also taken to center the window in the opening, setting the stage for effective air-sealing work, which will come later in the process.
Depending on the style of nail fin found on your particular window, the process of preparing the unit for installation may vary. On this Pella window, the metal fins are attached at the factory and folded down for shipping. After getting the nailing fins unfolded, the window is test-fit and traced, providing a target area for applying sealant under the fins. If all of the above is done carefully, setting and fastening the window is fast and easy.


Connect with Fine Homebuilding:

About Us: The demand for high-performance, energy-efficient home construction is growing every day, and Fine Homebuilding is at the forefront of that movement. From job sites across the country, we showcase innovative, affordable, and build-able solutions.

[acappellahymns]

Anyone know what screws are used in this nail flange? The Pella instructions mention a "jamb screw". I can't find "jamb screws" anywhere.