For the past few weeks, I’ve been explaining how to fix a broken window pane in your home. But what if you have dual pane windows? The process is the same? Well, more or less, except for a couple of variations. So, let’s go over the single pane repair process and I’ll point out the differences from double pane windows.
When we start talking about double pane windows, one of the first things that comes to mind is vinyl window frames instead of aluminum ones. When it comes to double-pane windows, you can have aluminum or vinyl frames, depending on the year the home was built. Double pane glass became popular in the 1980s, but vinyl frames didn’t really catch on until the 1990s. So if your home is less than 10 years old, chances are you have vinyl framed windows. . In any case, I will discuss the differences. Suppose you have an aluminum framed double pane sliding window. The procedure for removing the opening frame and pane glass is the same as for single-pane windows.
The differences are, first, that the glass goes into the frame about twice as much as a single-pane window. Single pane window glass is inserted 1/4″ into the surrounding rubber. Double pane is typically inserted 1/2″ into the rubber. So if both pieces of glass have broken, you’ll need to order a new IGU (insulated glass unit) from your local glass store. They’re going to want to know the width, the height, the overall thickness, and possibly the thickness of the individual glass. The best way to get the dimensions is to measure the width and height from rubber to rubber, write down those numbers. Then remove the panel from the opening and place it on a table as we did with the single pane window. Remove the screws from the opposite corners and pull out the frame. You will be able to see how far the glass goes into the surrounding rubber. If it’s 1/2″, then you want to add 1″ to the width and height you measured earlier (1/2″ down two sides = 1″). Next, measure the total thickness of the unit by removing the rubber from the edge of the glass.
Usually this dimension is 1/2″, but not always. There is a metal spacer that divides the two glass panes. Make a note of the color so you can request the same color on the new GUI. It will be silver or bronze If you want the same spacer size, you need to provide the glass shop with the thickness of each piece of glass in the GUI.If the old unit has 1/8″ glass on both sides, and the total thickness of the unit is 1/2″ spacer, then they will use a 1/4″ spacer. If the glass is 3/32″ on both sides, they will use a 5/16″ spacer. If you don’t mind matching the thickness of the spacer, you can request the thicker 1/8″ glass and they will automatically use a 1/4″ spacer.
When you get the new IGU home, the installation is the same as the single pane window. Now what if only one side of the GUI is broken? Many times the outer panel will break, but the inner panel is fine. You can order a whole new GUI like we just did, or if you’re the adventurous type, you can just order the single glass panel that broke and replace it. I’m going to explain how to do it, then I’m going to tell you the things that can go wrong. After you have removed the window panel on the table with the surrounding frame, you will see a black rubber type substance around the edge where the spacer is applied. This is a butyl sealant and broken glass needs to be separated from this butyl. The best way to do this is to take a utility knife with a new blade and break the butyl where it meets the broken glass. Next, take a new hacksaw blade and push it into the area where you separated the butyl from the glass. You don’t want the hacksaw blade attached to a hacksaw. Using your hand, saw from one side to the other while working your way around the edge of the glass. This should allow you to remove the glass.
Once this is done, place rags over the good piece of glass to catch any debris and abrade the surface of the spacer that will be in contact with the new glass. Use a spatula. Then remove the rags and debris. When you are ready to put in the new glass, clean the inside of the good glass that you did not remove. Remember, once you install the new glass, any residue or finger marks on the interior will be permanently sealed. So, give it a really good clean and check it from all angles. Do the same for the side of the new glass that will go into the GUI. Next, apply a thin bead of clear silicone around the entire perimeter of the spacer. Place your new glass on the spacer and press with your fingers to adhere the glass to the silicone all the way around. Then, approach from the side and run the silicone around the side where the glass and spacer meet. Cover the window opening with something for 24 hours. You don’t want to touch the GUI for 24 hours. The silicone needs to cure. After 24 hours, you can assemble the unit and install it back into the opening.
There are a couple of things that can go wrong. The first is leaving marks on the inside of the glass. Once he seals the glass, he can’t clean what’s between the panes. The other thing involves condensation between the panels. If you have even the slightest break in the silicone seal around the glass, you’ll likely start to see moisture build up as soon as the nights get colder and the days get hotter. You will have to decide if you are confident enough in your ability to do the job well, or if it is better to pay the extra money to have them do it for you. Just because you pay someone to do it doesn’t mean you won’t have the same problems. The difference is that they have to guarantee their IGU for a minimum of 1 year. I have received many units over the years that had marks between the glass. The beauty of this is that the manufacturer can’t argue with it, because no one else could have done it except them.
Well, what if the window frames are vinyl instead of aluminum? Well, the main difference is that a vinyl window glass no longer has the rubber gasket around the edge. It does not remove the screws from the opposite corners and separate the frame from the glass. What they do is put silicone or double sided tape on the edge of the frame where the glass rests. That’s what holds the glass in the frame, then they apply a snap stop to all four sides of the glass. Therefore, you must first remove the stops, then flip the panel over and break the seal that holds the glass to the frame with a utility knife. Wear gloves during this procedure. If only one side of the GUI breaks, don’t even think about repairing just one side. You’ll never get that GUI out of the frame without breaking the other piece of glass in the process. But, on the plus side, you can remove the stops without taking the panel off if it’s a slider. You can then measure the dimensions of the glass and order the new GUI. That way, you eliminate any need to temporarily cover your window. The same is true for the stationary part of a slider or image window. Before installing the new GUI, be sure to clean the edge that had the tape or silicone on it and apply silicone or tape. Either one will work.
You’ll find that replacing a GUI on an aluminum framed window is much easier than a vinyl window. But in any case, you can do it yourself and save a few bucks.