How to replace broken windows or glass panes in interior or exterior doors whether they are wood, metal, or fiberglass.
Interior and exterior doors may have glass panes installed to improve the function and appearance of the unit. Occasionally the glass may become damaged of cracked and need to be replaced. Instead of calling a professional window and door company to make the repairs, you can replace the glass panes yourself in a few hours. If the glass is for an exterior door and is insulated, it may have to be ordered through a glazer and installed afterwards. Interior doors are usually single panes and the glass can be purchased and cut at your local hardware store or home center.
Tools and Materials
Stiff Putty knife
Exterior Door Glass Repair
1. Remove the trim around the glass pane on the interior side of the door. Depending on how the door was made there are several ways in which the trim can be applied. On fiberglass or steel doors, the molding may be a molded vinyl unit that is held in place with screws. There are usually caps covering the screws that can be removed with the tip of a utility knife. Other times the screws may be covered with glazing compound or caulk. When this type of trim is removed it may be screwed into the door or to the other trim on the opposite side of the door. For wood doors the trim may be either wood or vinyl that is nailed or screwed into the wood of the door. Use caution when removing the trim so as not to damage the pieces.
Wood trim holding the glass pane
2. For exterior doors the trim on the outside may also be caulked. Scrape away any caulk or glazing compound that remains on the door and remove any spacers or glazing pins that are holding in the broken piece of glass.
3. Measure the old glass pane if it is intact and purchase a new piece to match.
4. Test fit the new glass pane in the opening. If the unit fits and there is at least 1/8-inch gap all the way around, place a thin bead of clear silicone caulk on the back side of the trim that is already in place. Place the new piece of glass against the caulk trying not to slide it around in the frame. Reuse the existing glazing pins or spacers to center the glass in the opening.
5. Re-install the molding using the same fastening method as it was originally installed with. If the trim is wood, pre-drill the molding and use 4d nails or brads to secure the trim.
Interior or French Door Glass Repair
French doors typically have individual glass panes, called a true divided light door, which are held in place by wood trim. The trim forms a frame around the outer edges of the pane on both sides of the door. The trim can be nailed or stapled in place, and on exterior doors, glazing compound or caulk may also be used to provide a weatherproof seal.
1. Insert a stiff putty knife under the trim of the broken pane to remove. Be careful not to damage the trim as it may be difficult to find an exact match. With pliers or a small pry bar, remove any nails, brads, or staples that remain in the door after the trim has been removed.
2. Wear gloves to remove the broken pane from the French door. Clean off any glazing compound of caulk that is on the door or the back side of the trim that remains.
3. Take the broken pane to a home center or glazer and have a piece cut to size. If possible, remove an unbroken pane to obtain an accurate measurement. You can also measure the opening for the glass pane and subtract 1/4-inch from the overall length and width to allow for a 1/8-inch gap all the way around.
4. Place the new glass pane into the French door. Slide the pane back until it is pressed up firmly against the back edge of the trim on the opposite side of the door. The pane should fit snugly into the opening. You can purchase glazing points or plastic shims to help center the glass in the opening. The gap should be even between the wood mullions and the pane.
Note: If the glass rests against the wood it may crack as the wood shrinks and swells with changes in the humidity and temperature or when the door is opened and closed.
5. Remove any nails or staples from the trim with a pair of pliers. Reinstall the trim around the pane. You can pre-drill new holes through the trim to make the nailing easier and lessen the chance of damaging the new glass. Place a small amount of wood filler on a putty knife and fill in the nail holes.
6. Sand the filler with 120-grit sandpaper after it has dried and then apply a coat of paint over the trim.