How to Repair Foggy Double-Paned Glass Windows


Double-paned windows can easily fog up once the seal has been broken between the panes and moisture gets inside of the window. You'll need to do something to fix the problem before the double-paned window fogs up so bad that you can't see out of it anymore, but you're options can be very limited. Repairing the seal typically does not help in restoring the window to its original transparency, because once the seal is broken, the gases or pressurized air inside the window that keeps the condensation from building up inside of them is released. One option is to purchase a new insulated glass unit (IGU) to put into the window frame. Here is how you can purchase and install a new IGU.

You Will Need:

  • New IGU Window
  • Measuring Tape
  • Silicon Caulking
  • Putty Knife
  • Wet Rag
  • Plastic Sheeting
  • Cardboard

Remove Old IGU

You will need to remove the old IGU from the vinyl sash. Take your putty knife and slide it under the glazing beads on the inside of the window sash and pop the beads out. Remove all four glazing beads and flip the window over. You will want to slide the putty knife between the IGU and the sash to break the silicon caulking seal so you can remove the IGU. Clean the sash frame by taking your putty life and removing all the silicon caulking on the inside of the frame until you get a nice clean surface for the IGU.

Ordering New IGU

Take precise measurements of the width, length, and thickness of the old IGU unit before ordering a new one. You will need to order a new window and will usually have to wait at least a few days before until it arrives—make sure you put plastic or cardboard into the open window space to keep animals and debris from getting into your house while you are waiting.

Installing New IGU

Put silicon sealing material all around the inside of the sash. Take your new IGU and place it into the sash and gently push it against the frame – if some of the silicone caulk squeezes out onto the window, take a wet rag and wipe the window until the silicon is removed. Replace the beads and put the window back into window frame.

If you think you need help with the window, you should contact your local window replacement company (such as Cheaper Window Glass) to come in and assist you.


7 April 2015

Understanding Window Upgrades For Commercial Buildings

Hello, my name is Donald Clemins. I am here to talk to you about windows for commercial buildings. When I purchased my first storefront, I was shocked to feel cold drafts coming in through the picture windows. The drafts made it feel like the front door was propped wide open. I knew my customers would feel uncomfortable sitting there due to the drastic temperature fluctuations. I contacted a window installer to talk about my options. I was amazed to hear about all of the different types of windows available for my storefront. I would like to share that information on this site to help other people find the best windows for their commercial buildings. I will focus on window material and build upgrades as manufacturers make new developments. Thank you.