How to Replace a Broken Vinyl Window
- 1). Measure the width and height of the opening, moving the sashes of the old window up and down as needed to access the sides. Order a new vinyl window unit with those dimensions. Leave the old window in until the new one arrives.
- 2). Remove the trim from the inner edge of the opening, using a hammer and a pry bar. Don't break the trim as you remove it, so you can reuse it later. Remove the sashes, which should come right out with the trim removed.
- 3). Stand the new window unit in the opening, with the bottom first. Push in the top until it's stopped by the exterior border of trim. Place a level on the unit and insert shims around the sides to get the unit level.
- 4). Secure the unit in place with wood screws. Drive the screws through the screw holes and into the sides of the opening with your screwgun.
- 5). Spray foam insulation into the gap around the perimeter of the window unit.
- 6). Set the trim back in place around the edges so that it covers the insulated space. Secure it with finish nails and your hammer, driving the nails through the side frame, not the window casing. Caulk all the lines around the trim and the casing.
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