How to Secure Double-Hung Windows
- 1). Remove the old windows by prying off the thin, narrow strip of trim that surrounds the window on the inside of the opening, using your hammer and pry bar. Don't break the trim as you remove it, as you will reinstall it later.
- 2). Pull out the existing windows, into the room. Leave the exterior border of trim on the outside of the opening in place.
- 3). Set the new double-hung window unit into the opening, first setting the bottom of the unit onto the sill of the opening and then pushing in the top. Push until it is stopped by the exterior border of trim.
- 4). Set your level against a vertical side of the new unit. Push shims in along the sides of the unit, until the level reads plumb. Move the level to several spans of the window and shim until it's level and plumb throughout.
- 5). Drive the long mounting screws that came with your window in through the screw holes on the sides of the unit, sinking them from the inside out to the surrounding wall, through each of the provided screw holes with a screw gun. There will generally be two or three screw holes on the each vertical side. Don't overtighten the screws, but get them snug.
- 6). Spray insulation foam spray into the space around the window unit, filling it completely.
- 7). Reinstall the interior trim border with your hammer and trim nails, covering the space and trapping the new window unit in place. Caulk around the trim inside and out.
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