To repair window leaks, homeowners need to identify the exact location of the leak, repair any rotted wood or damaged trim around the window, and fill voids with wood putty. Caulking is used to further repair leaky windows.
Homeowners should identify all leaks before making repairs. To identify the leak, the homeowner sprays a light misting of water along the outside of the window while another person inside the home marks the exact location of the leaks.
The homeowner then removes the trim around the window, removes any rotted wood behind the trim with a putty knife, and fills the gaps with wood putty. The trim is replaced, and caulking is applied to the trim. When using caulking, one may cut the tip of the caulking tube at a 45-degree angle to apply the caulk properly.