How to Install a Milgard Window

Michael Kozlowski

Milgard windows are vinyl replacement units that are fairly easy to install. The key to window installation is ensuring that the window opening is properly prepared to accept the window. It is a job that can be completed by a homeowner with some carpentry skills.

Milgard offers varying styles of windows such as double-hung, slider and casement. The company also offers specialty windows designed for hurricane-prone areas or for sound abatement. All the windows install in the same basic way.

  1. Use the razor knife to cut away caulk securing the interior and exterior trim. Remove the trim so the frame of the window is exposed.

  2. Cut around the exterior of the window with the electric saw. Depending on the type of existing window, you may need to cut through the nailing flange. Nailing flanges are common on new windows, but cutting through them to replace them lets you avoid needing additional work to the home's exterior finish.

  3. Check the window frame, commonly referred to as a buck, to ensure that it is square and level. You can use shims and a 1x4 to build an interior buck that is square without reducing the window size much.

  4. Place the Milgard window in the buck frame. Use shims to ensure that it is snug and sitting square. Screw through the interior of the vinyl frame to secure the window to the buck. The screws can be used to help adjust the window into position and for squareness.

  5. Push strips of batt insulation into any gaps between the window and the frame. A shim can be used to push the insulation into place.

  6. Interior trim can be replaced or reinstalled easily with trim nails. Nail the trim to the buck frame, not to the window. Use a silicone caulk to mate the trim to the vinyl.