How to Replace Basement Casement Windows
- 1). Take the trim off the inside of your basement window on the inside and outside by carefully prying it from the wall with a pry bar; try not to damage the wall or the trim. Do the same with the exterior trim from the window, but also cut away old caulking with the utility knife and remove insulation from around the window with the putty knife. Save the insulation.
- 2). Lift the old window carefully out of the opening from the outside; you may need a friend to help you. Dust off and lean any debris or old pieces of caulk from the window frame; use a whisk broom, putty knife and utility knife.
- 3). Apply a bead of exterior caulk around the perimeter of the inside flange of the new window, using a caulking gun. Insert the new window in the opening with the help of your friend.
- 4). Hold a leveling tool against the window to ensure it is sitting level. Insert wooden shims in low spots to raise it so it is even with the level. One of you should hold the window in place while the other uses the nail gun to insert nails through the flange into the window framing to secure the window.
- 5). Apply more exterior caulk with the caulking gun around the window from the outside between the brick and the wood framing. Spray aerosol urethane foam insulation into any remaining space.
- 6). Cut pieces of exterior trim to fit over the edges of the window, using the power miter box; cut the ends at a 45-degree angle so you can fit them together like a frame. Apply exterior caulk to the back of the pieces of trim and the ends as you fit them together; nail the trim to the frame with the nail gun. Apply another bead of caulk where any gaps appear between the brick and wood around the window. Apply wood putty with the putty knife to fill the nail holes; when dry, sand the putty with the sandpaper, prime and paint the trim with the paintbrush and exterior paint.
- 7). Affix the wood shims with the nail gun by nailing them to the wood frame on the inside of the window. Cut off any edges that protrude with the utility knife.
- 8). Insert the old window insulation from the inside to fill spaces between the wall and the window. Use your hands and a putty knife to push it into the gaps.
- 9). Affix and finish off the interior trim to the inside of the window, the same way you did the exterior trim, but apply spackling instead of the wood putty on the nail holes and interior grade paint on the trim.
