How Do You Repair a Basement Window?

Replace a Basement WindowIt is important to repair a basement window if it is broken or damaged to maintain the safety of your home, prevent creatures from entering your home, and prevent weather damage to your home. Make sure the aluminum or steel frame of the window is not too damaged so that you can repair the window instead of replacing it. Your basement window can be framed in concrete or wood. Also, if there are cracks around the window you will need to cement these cracks to prevent damage due to flooding.

Tools Needed

Based on the type of basement window your home has you will need the following tools to repair a basement window: chisel,utility knife, metal grate, wire brush, cement (cement masonry), trowel, bucket, glazing, hand sledge, drill/drill bits, pipe, brackets, well duct, primer, paint coat, reciprocating saw, caulk, safety goggles, and urethane foam. The correct tools should be selected based on the type of basement window that needs repair.

Removal of Glass

First, to repair a basement window, you will need to remove the broken glass to repair the glass pane and metal in a window. If the metal is not broken, you will need to remove the glass and clean the window frame with a wire brush. You can also use black enamel to give the window frame a completely restored look. Take the screws out of the window to remove the frame that is attached to the masonry. Cut through the painter chalk or the caulking. A utility knife placed and pulled between the window frame and masonry will pull out the frame. Use the utility knife to go around the frame and masonry to pull the frame from the home ensuring you preserve the metal frame. Make sure you measure the glass panes and order or purchase the correct size.

If the basement is flooding, because of cracks and holes around the window, inspect the window to see where the cracks are coming from. If you find a crack use a chisel and a sledge hammer to increase the cracks size and chip away the sidings. After this is complete, use cement to close in the crack, with five parts cement to one part water. Then use a trowel to ensure the cracks are completely filled in.


The first step in glazing is to remove any chalking or other substance from the metal or wood window frame. Then you use a glazing product such as UGL or Dap. Make sure you clean the frame properly with a wire brush and soap and water completely drying the frame before installing the glass. Take some of the glazing and push the glazing around three sides of the window and smooth it around until it covers three sides, leaving the top bare. The top portion is left without glazing until the new glass is laid in place. Gently press on the edge of the glass to seat on the glazing and is catching the edge of the glazing. Work your way around the glass to make sure each part of the glass is lying smooth in the bed of the glazing. If there are retainers, position them on the two end sides of the window to hold the glass in place. Fill the top gap of the window now with the glazing. Afterwards take a knife to clean off the glaze leaving enough to create a good seal.

Re-Installing Window

After the repair has been complete you will then need to reinstall the window. Secure the window in place with the correct screws. For example, if the masonry is concrete, utilize concrete screws. Caulk the inside gap between the masonry and the window. From the outside of the home fill the gap between the window and the masonry with spray foam to ensure a tight insulated seal, according to Fine Home Building.

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Repairing a basement window can be a do it yourself project and will protect the value of your home. It is a moderate intensive project to repair a basement window and can save $4,000.00.