A bead of caulk should be placed around the opening within 1/4" of the edge. Center window in the opening, there should be approximately 1/4" -3/8" space on both sides between opening and window, firmly seating it into the caulk. Partially secure one top corner with nail in pre-drilled hole. Do not fully set nail all the way.
Cut a 3" wide strip of fiberglass insulation and lay it on your sill prior to setting the new window into the opening. This will help prevent drafts from entering under the window.
Verify unit is plumb, level and square (See Figure 2) . If needed use wood shims to ensure window is level and square. Do not over shim.
Check sash for easy operation; close and lock window. Unit will not operate smoothly if not square or overshimmed. Complete installation on the outside by driving 1 3/4" galvanized roofing nails all around perimeter, in every other slot.
Cover the cut edges of the rough opening with 9" strips of flashing paper or other moisture resistant flashing such as Tyvek, building tape, etc. Staple or nail into place. Put bottom strip on first leaving bottom edge of paper loose so building paper can be slipped under it later. The side strips are applied, overlapping the bottom strip and extending 6" above the window opening height and the top strip of flashing paper, after the window is installed and over the nailing fin. (See Figure 1)
Fill in any cracks between sides of unit and existing casing with fiberglass insulation (or non-expanding, low pressure foam insulation).
Apply exterior siding, stucco, brick, etc. Allow sufficient clearance around perimeter of windows. Caulk around entire perimeter of window unit and under sill.
Effective Date: April 11, 2011
Prices are subject to change without notice.