Homeowners with double paned windows report better insulation from cold, heat, and sound. When a seal is broken or damaged, however, gasses can escape from between the panes of glass, and moisture can leak in. This often causes condensation between the windows that can be difficult to remove. If your window is not covered by a warranty, sometimes this condensation can be removed by drilling small holes in the outer pane of glass. Other times, though, one of the panes of glass needs to be replaced.
If your window is fairly new, there is a good chance that it is still under warranty. Most window companies provide warranties that cover condensation problems for their double paned windows. The company will typically send a repairman to fix your window for little or no money, depending on how old the window is.
If the warranty has expired or you aren't sure who made the window, you have a couple other options. Some companies claim they can remove condensation from double paned windows. During this process, two small holes are drilled in the window, one at the top and one at the bottom. Many times repair workers will wash between the glass as well. Afterward, the gases between the window panes will be replaced, and the holes will be plugged.
Some of these companies, however, only recommend this method for windows less than ten years old. For older windows, they recommend replacing the window, or at least one of the panes of glass. Some do-it-yourselfers may be able to get rid of condensation between their double paned windows using a similar method. It can possibly be a dangerous procedure, though, and the proper safety equipment should be worn. Also, because the glass can easily break during this procedure, it should not be done unless you are fully prepared to buy a new window.
After putting on safety goggles and heavy gloves, use a glass drill or a diamond bit to drill a 3/8-inch (6.77-centimeter) hole at the bottom of the outside pane of glass. This should be drilled at an upward angle. To reduce the risk of the glass shattering, be sure that the bit your are using is always wet. This can be accomplished by slowly dripping water on it while you are drilling the hole. Also, this should not be done during extreme cold or if your window is in direct sunlight.
When you have managed to get the hole drilled, insert a 1-inch (2.5-centimeter) piece of tube into the hole, and seal around it with silicone caulk. To stop bugs from getting between the panes of glass in your double paned windows, some type of screen or filter should be put into the tube, and a small bit of steel wool can be used. It will usually take a few weeks, but the condensation should clear out.
If this method does not work, or the glass shattered while you tried to drill the hole, you will probably have to purchase new double paned windows. You may be able to just replace one of the panes of glass. Many companies recommend buying a whole new window, however, if it is more than ten years old.