How to Repair Aluminum Windows

Lead Image
  • 2-3 hours
  • Beginner
  • 30-130
What You'll Need
Protective gloves
Rubber mallet
New pane of glass

Aluminum windows do a great job, but, like all windows, accidents can occur that cause the glass to crack or break. This ultimately leads to replacing the glass. Although you can pay a glazier to come in and do the job, it's surprisingly easy to do it yourself. All it takes is a little hard work and you can have your window back in place and looking like new, whether it’s a sliding window or a stationary one. There’s no special skill involved, nor do you need any specialist tools you don’t already have in the house.

Step 1 - Removing the Old Window

If you need to replace the glass in the slider part of your aluminum window, the task is remarkably easy. In most cases, all you’ll need to do is lift up the bottom of the window, swing it out toward you and remove the window. In other instances, there might be a roller at the top and you’ll need to remove the screw holding it in place first.

With a stationary window, first remove the slider then unscrew the center bar holding the aluminum window in place, using the mallet to tap it to the side. Now, use the mallet the gently tap the window out of its channel then lift it out.

Step 2 - Removing the Glass

Put on protective gloves before you begin to remove the glass. Locate a screw in the bottom left hand corner of the frame. Unscrew it until it falls away and keep to one side. Next, do the same in the opposite (top right) corner. The frame will now be in two halves. Using the mallet, tap the frame gently away from the glass on one half. Put the frame aside and repeat on the other half until the glass is free with a rubber gasket around it. Remove the gasket and clean out thoroughly, keeping it to one side for putting on the new frame.

Step 3 - Selecting New Glass

You’ll need a new piece of glass the same size as the old one but an important factor to the job is determining whether you need single or double strength glass since one is thicker than the other and the wrong size won’t fit easily into your frame. Single strength glass will be 3/32 inch thick and double strength will be 1/8 inch thick. The difference might seem minor, but it’s very important when it comes to fitting. If you’re not sure, take a piece of the old glass to your glass shop and let them advise you.

Step 4 - Fitting New Glass

Put the glass on a table with one long side and one short side overhanging. Fit the rubber gasket tightly on those sides. With the gasket in place, take one half of the frame and place it over the glass, tapping the corner into place with the mallet. When that’s secure, tap the long side and the short side into place.

Now, move the glass so the other two sides overhang the table and repeat until the frame sits firmly on the glass. Replace the screw in the corners and re-hang the window. With a stationary aluminum window, replace it in the channel, put the center bar back in place and secure before fitting the sliding window.