How to Replace Aluminum Windows With Installed Vinyl Replacement Windows
- 1). Measure the width of the existing window openings, measuring from inside the aluminum tracks that the sashes sit in. Raise and lower the sashes as necessary to get the measurements. Subtract half an inch from the number you come up with. Repeat the process for the height of the opening.
- 2). Order your vinyl replacement windows with the adjusted measurements. Don’t remove the old windows until the new units arrive.
- 3). Pry off the thin strip of wood trim that runs along the inner perimeter of the opening, holding in the old window sashes. Pull the sashes straight in. On some types of aluminum windows, the tracks of the windows will be screwed into the frame house. If so, remove it by removing the screws.
- 4). Remove the outer aluminum storm windows, if there are any, by unscrewing the small mounting screws that hold it to the outside of the frame.
- 5). Lay a piece of fiberglass insulation over the sill of the window opening. Set the bottom of the new window unit on top of it. Push the top of the unit up into the opening, until it comes to rest against the perimeter of trim along the exterior of the opening. Tuck insulation into the spaces around the sides and top.
- 6). Set a level on the unit and use shims to level it out, tucking them along the sides and bottom as needed.
- 7). Drive 3-inch mounting screws through the screw holes in the sides of the unit and into the house frame with your screw gun.
- 8). Re-install the perimeter of interior trim that you took out, nailing it in place with a trim nailer to trap the window in place. Use your caulk gun to seal off the perimeter of the new unit where it meets the trim.
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