Residential New Windows Installation Instructions
- 1). Measure the dimensions of the window opening, taking several readings with your tape measure at different points across the width and length (in case the opening isn't exactly square). In each case, measure from the inside of the track where the window sashes sit, moving the sashes up or down as needed.
- 2). Take the smallest span that you find across the width, and subtract half an inch from it. Do the same for the length. Order the new window unit using those two dimensions. (The half-inch subtraction will allow you to leave 1/4 inch of space all around the new window in the opening, so you can adjust its position.)
- 3). Receive the new window and remeasure it to make sure it's right. If it is, then remove the old window sashes, by prying off the thin strip of wood trim positioned in front of the sashes, then pulling the sashes inward toward you. Don't break the trim while you're taking it off. Set it aside. (Note: Remove only the trim around the interior edge of the opening, not the trim around the exterior edge of the opening.)
- 4). Lay a piece of insulation along the bottom of the window opening. Stand the bottom of the new window unit on top of the insulation. Push the top of the unit into the opening, pushing insulation in around the sides as you do. Push until the unit comes to rest against the wood trim that's around the outer perimeter of the opening.
- 5). Check the unit for level, holding a level against it at various points. Shim the unit along the bottom and sides until it reads level throughout. Secure it there by driving 3-inch screws through the screw holes in the sides of the unit, out into it the surrounding frame.
- 6). Nail the trim back in place around the interior edge of the opening, so it traps the new unit in place. Caulk the line between the unit and the trim, inside and out.
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