How to Replace Windows in a Townhouse
- 1). Take the measurement of each window opening, measuring the height and width, while the old windows are still in place. Move the window sashes as needed to get at the sides. Measure each window separately. Order the replacement windows using those measurements.
- 2). Remove the trim from the perimeter of the first existing window, after the new window units arrive, using a prybar and hammer. Keep the trim intact as you remove it, as you will have to re-install it. Set the trim aside. Remove the window sashes.
- 3). Set the replacement window unit into the opening, putting the bottom in first, and then pushing the top in. It should come to rest against the trim around the perimeter of the opening. Set a level next to the unit, and shim around it until it's level.
- 4). Use a screwgun to shoot installation screws through the holes that are in the sides of the window unit. Shoot the screws outward, affixing the unit to the surrounding frame.
- 5). Spray foam insulation into the spaces around the perimeter of the replacement window unit.
- 6). Put the trim back in place around the window with a finish nailer, covering the spaces and trapping the window unit in place. Caulk where the trim meets the wall and the window. Repeat for each window in the townhouse.
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