Sliding glass door condensation

August 23, 2010 4:58 PM

How to deal with condensation between panes of a sliding glass door?

We bought a house a few years ago (and so are not the installers) that features a larger than standard size sliding glass door. As of this summer, we have condensation on the sliding portion of the door. Googling suggests that we may need to have the glass replaced to fix the problem. Drilling holes in the glass is beyond our skill set. Is there anything else we can do to ameliorate this? If not, roughly how expensive would this be to have fixed (mid-Atlantic US location)? When winter arrives, will frost/freezing pose a threat of shattering?

posted by Morrigan to home & garden (8 answers total)

We've had foggy, condensed, frosted double glazed windows for years without being shattered by a Toronto winter but it needs replaced.
posted by bonobothegreat at 5:10 PM on August 23, 2010

I've had windows like this (Michigan). Drilling holes won't fix it. I doubt there is any problem with freezing/shattering. There isn't anything you can do short of replacing the glass. Call a window company, you should be able to get a free estimate.
posted by HuronBob at 5:16 PM on August 23, 2010

Depending on how old the door is and who made it, the glass may still be under warranty-- Anderson, in particular, I believe, has a pretty generous policy in this regard. Worth investigating, since I'd imagine it'll be fairly pricey to replace on your own dime.
posted by Bardolph at 5:27 PM on August 23, 2010

The glass in your door is made up of two (sometimes three) layers of glass separated by a airtight aluminum extrusion and silicone sealant. This creates a dead air space which makes the glass more energy efficient, the seal has failed and you are getting condensation between the panes. This seal cannot be fixed. You have to replace the glass if you want the thermal performance that the door is supposed to have and/or to get rid of the fogging.

This condition does not effect the strength of the glass and freezing will not cause the glass to break.

Drill holes will not do anything to solve this problem and in fact if one is not careful could break the glass.

I second checking on the warranty some are good for up to ten years.

As long as this is not a totally strange custom size replacing the door sash is generally a simple job.
posted by flummox at 6:07 PM on August 23, 2010

What flummox said
posted by misterbrandt at 7:30 PM on August 23, 2010

We just had the glass replaced in our sliding glass door for this exact same reason. It was like this for several years, with no cracking problems.

The local glass company that did the replacement for us gave us several options in glass, and we chose a low-e glass, because we had sun damage on the flooring right by the door. There are less expensive types of glass available. I did not think it was all that expensive, however. We replaced that and the glass in a smaller window for less than $1000.

It's way cheaper than replacing the entire door, and will help with your heating bills in the winter. Some replacements can qualify for an energy credit, though ours did not because we have aluminum frames.
posted by annsunny at 8:17 PM on August 23, 2010

Tempered glass is impossible to drill.
posted by hortense at 9:12 PM on August 23, 2010

Sometimes you can fix it without replacing the window. I saw a guy drill a small hole in the glass (non-tempered) and then cover it with a gore-tex patch. The patch allows water vapor to escape but keeps liquid water out.
posted by electroboy at 6:53 AM on August 24, 2010