There are several important factors to remember when installing a window.
Almost all new construction windows have nailing fins to install them with. I use 2” long roofing nails to install windows with nail fins.
STEP 1: Verify that the window fits the opening.
STEP 2: Apply construction adhesive to the backside of the nail fin and set the window in place.
STEP 3: Place a ¼ spacer under the bottom of the window on both sides.
STEP 4: Center the window left to right in the opening.
STEP 5: Plumb the side of the window.
STEP 6: Re-center in the opening if needed.
STEP 7: Place two nails, one at a top corner and one at a bottom corner.
STEP 8: Re-check the plumb.
STEP 9: Finish nailing the window in place.
STEP 10: Remove the spacers from under the bottom.
The window should be suspended in the opening, not resting on the bottom plate.
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