I have a double pane thermal window. In the winter, it builds up condensation inside the panes. I was wonder if the repair is something a DIY’er could do.
My thought was to let it dry out during summer and then caulk it. But then I was told that there usually is a gas inside the panes (which I assume is long gone now).
Is the gas what’s providing the thermal value of the window? Or is the water/air tightness of the double panes what’s providing the thermal value? If it’s the latter, I figure just caulking it sealed should do the trick.
What do you think? Thanks in advance for your help.
Replies
The gas inside isn't important. In many cases it's just air, and air is just fine so long as it's dry.
But repairing thermal windows isn't terribly practical. A few people claim that drilling a couple of small holes through the outside pane will work, but the window will still fog some and will eventually get dirty inside.
If you can access the edge of the pane, and if it uses metal spacers, you can accomplish something similar by drilling through the spacers, then providing holes in the frame that "communicate" with the outside.
A few people claim to have had success opening the windows up and drying them out, but it's iffy at best. You could, in theory, drill through the sides, bake the window for mabye 24-48 hours at about 150F to dry it out, then seal the holes with urethane caulk or some such. Of course, the original leak will still be there so the window will eventually fog again.
If you can't get it completely and permanently sealed, the other approach would be to go to the opposite extreme, and build something that can be readily opened all the way, so you can get access to all four glass surfaces, and clean it out whenever it needs it. This has worked well for centuries in northern and eastern Europe, where they have casement windows with two sets of sash in each jamb, one outswing and one inswing.
-- J.S.
Note that "letting it dry out in the summer" won't do it as summer air is quite humid. You need to either bake the window or place it in a low humidity chamber for some period of time.
I have thought about experimenting with getting a cylinder of dry gas from the welding supply outfit (argon or nitrogen, perhaps) and then using something like a football inflating needle to introduce the gas into the space between the panes. A similar needled on the opposite side would be required to allow all the existing moisture laden air to be flushed out. The holes made for the needles would then be resealed. This would require some type of adapter from the pressure reducing valve on the gas cylinder to mate with the needle.
What I don't know is the nature of the seals and what precautions need to be taken when creating the hole for the injection and exhaust needles through the seals. I also haven't researched yet what type of material would be best to reseal the holes in the seals.
Don't have any bad windows at the present to play with, however...
Note that you don't simply need to replace the air in the unit with dry air, you also need to dry out the drier that is generally imbedded in the aluminum frame. It's something along the lines of silica gel.
Get a price on new glass. On average for double hung window it's less then $40.00 per piece uninstalled. Now is it really worth all the work suggested?
Also check the replacemnt suppliers warrenty. A 1 year warrenty means they probably aren't doing a real good job.
$40 for a replacement pane sure sounds easy. I think I'll go with that. I have no idea what the original warranty is. The previous owners replaced all the windows about 9 years ago. I've been in the house almost 5 years.
There are a few lumber yards, a Home Depot, and a Lowes in the area. I'll check to see if any of them carry replacement panes for my window model...now let's hope the manufacturer's info and model # is somewhere accessible.
Note that most brands are warranted for ten years, and several of the better ones have lifetime warranties.
The manufacturer and manufacturing date are often stamped on the metal spacer in the window, visible through the glass.