How to Replace Drafty Windows
- 1). Remove the storm window from outside the building. First, remove its sash by pulling inward on the two latches to lower it. While still holding the latches, tilt the bottom outward and rotate the sash a little to free the top edge from the tracks. Remove any debris from the tracks with a hand vacuum.
- 2). Clean the metal part of the sash with a damp towel.
- 3). From inside the building, use a utility knife to cut the paint and caulk between the sash stop and the window casing. Insert a putty knife in between the sash stops to loosen it. Then use a prybar to remove the sash stops.
- 4). Remove the upper sash, lower sash, and window crack. Also remove the parting strip with a pair of pliers. Use a caulk gun to apply silicone sealant to the bottom corners and outside stops of the window.
- 5). Insert the new, replacement window into the threshold. Make sure that the new window sits in the threshold firmly and square. Install window shims to the top, bottom and middle of the sides of the frame. Drill screws into the pre-drilled holes. Drill screws on the sides of the window as well as through the shims and into the jamb.
- 6). Fill in gaps to prevent air drafts between the frame's edge and the window opening with low expansion foam. Replace the sash stops that were removed earlier and secure them using a nail gun.
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