Single Pane Glass Repair in an Aluminum Frame, Part 2

This week we are going to continue our series on single pane window glass repair. Let's talk about broken glass in a fixed window, usually referred to as a picture window. The most common type will have metal stops on the outside, around all four edges of the window glass. Sometimes these stops will be held in place with screws, and other times there will be aluminum stops that snap in place. In some rare instances there will be a rubber material in place of metal. If you have the screw type, you remove all of the screws and each piece will come out. If you have the metal snap in stops, carefully pry the stop from the frame using a small, flat screwdriver or a putty knife. You want to start in a corner and work along the stop until it comes out. Don't pry too much because the stops can bend very easily. If you have the rubber type, pry a corner away using the screwdriver, grab it with your fingers, and pull out the rubber. The glass shouldn't fall out because there is a glue or tape on the edge, holding the glass in place.

From here, You can get your measurements for the new piece of glass. The glass edges will be exposed, and you can hook your tape measure to the edge and get your width and height. If there is a hole in the glass, measure the glass thickness. If there isn't a hole, put on some gloves and carefully push on the glass where the crack is located. This will expose the edge so you can measure it. When you go to get the new glass, you're going to need a tube of silicone to replace the glue or tape holding the glass in place. Once you get the glass home, you need to remove the old glass. Go inside and cut between the glass and frame using a utility knife with a new blade. This will cut away the silicone or tape that is holding the old glass. Be sure to wear heavy gloves during this process to avoid getting cut. Start at the top and cut across from one corner to the other. Then cut down one side, from top to bottom. Do the other side the same way. At this point the glass should fall out. You should place a tarp or sheet under the window to catch the glass as it falls out. Using a stiff putty knife, scrape off the old silicone or tape from the frame. If there were setting blocks on the bottom, be sure to reuse them. They act as shims to raise the glass off the bottom.

Now run a bead of silicone about 3/16" thick around the perimeter of the opening. Grab your new glass on the sides, angle the bottom in and the top out, set the glass on the setting blocks, then slowly raise the glass up into place. Push just hard enough that all four edges of the glass contact the silicone, but not so hard that the glass makes contact with the metal frame. Install your outside stops. Don't clean the glass for 24 hours so the silicone can set up.

Next week I will continue this series on window glass repair.

John Rocco has been installing replacement windows since 1978. To learn more, visit How To Install Windows