- 1). Remove the interior window trim by positioning a putty knife between the wall and trim. Insert a pry bar to gently pry the trim and nails from the wall without damaging it if possible.
- 2). Cut away old caulk from the exterior trim with a utility knife. Pry away the old trim with the pry bar. Lift out the window with the help of a friend. Clear away old insulation and caulk with the putty knife from the window opening. Save the insulation,
- 3). Caulk the inside flange of the new window along the length of the flange with the caulking gun and exterior caulk. Place the new window in the opening with the help of a friend. While he is holding the window in place, nail the flange to the frame of the window with the nail gun.
- 4). Level the window. Hold a level against the edge of the window and place it in a level position by inserting wood shims to lift it where it sits low. Insert the shims between the edge of the frame and any openings.
- 5). Secure the window to the frame by nailing the flange into the frame with the nail gun and nails from the outside of the window.
- 6). Caulk with the caulking gun and exterior caulk around the window flange between the brick and the wood framing. Insert a piece of 2-by-4-inch pine that was previously cut to fit the gap between the wood frame and the brick. Fill remaining spaces by spraying aerosol urethane foam insulation in the gaps.
- 7). Cut pieces of exterior trim, using the power miter box so edges are cut at a 45-degree angle. Caulk the back and abutting edges of the trim with the caulking gun and caulk and install the trim. Nail the trim with the nail gun to secure it to the frame. Caulk a final bead of caulk in between any gaps in the brick and wood around the window.
- 8). Fill the exterior trim nail holes with wood putty. Sand it when dry, and prime and paint with exterior paint and a paintbrush.
- 9). Secure the wood shims from the inside with the nail gun and cut off any protruding edges with the utility knife or handsaw. Replace the insulation from the inside and fill any gaps between the wall and window.
- 10
Install the decorative molding as you did with the exterior molding; first cutting the edges to a 45-degree angle to fit them together. Nail them with the nail gun on top of the casings. - 11
Apply interior spackling compound with the putty knife to fill nail holes on the trim. When dry, sand it and apply an interior primer with a paintbrush and then a layer or two of interior trim paint.
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