Moisture inside double pane glass doors.

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Feb 15, 2003
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Jupiter, Florida
My Florida home has 4 sets of french doors (so 8 doors total) and the double pane glass in most of them is fogging up badly. They are 18 years old. The doors are made of steel, and have only a minor bit of surface rust on them at the bottom. I believe I can clean that up easily (but ya never know) . The glass is held in by a retainer and screws. The window panes are large simple panes and take up most of the door.

I'd like to replace the glass. I have been looking for wind resistant hurricane glass (custom size) , unfortunately the companies that sell this don't sell it as single pane, and a double pane hurricane glass won't fit (too thick) .

Maybe a 3/8 inch thick tempered glass? I'd even consider a quality plastic, but I don't think that option is reasonable, as very few Plexiglas products hold up.

So, I'm looking for suggestions. I'd prefer not to replace all the doors, not just due to the expense, but the fact that I really feel that any quality replacement glass will work just fine and it seems quite easy to do.

EDIT: The doors seem to be quite tough, they open outward for wind resistance, and meet the 175mph wind load rating (just not impact) . The company that made them is out of business.
 
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I have the same problem. As far as I know, the only option is to find a glass guy that is willing to just replace the glass pane but that is not so easy. Maybe a handyman that knows glass.
 
I would think if there were a market for just replacing the glass then it would be available. In any case you still want to have the insulating properties of double-pan glass so I would not expect a re-seal in the field to be as durable as an initial seal in the factory.

IMO..New Doors.
 
You guys are hosed. There is much more to getting hurricane rated doors than just the glass. Any Florida inspector will want to see the manufacturers certification for that specific door. The good news is that if they are covered by storm shutters, depending on type, you may get a waiver from the inspector on the glass, but he will still want to see ratings on the frame.
Here in central Florida, I think 35 mph wind is suitable for the frame. The Miami-Dade codes might require something more.

Now, to get all that accepted by your insurance company for "Wind Mitigation" would be a different story. They might go for it. They can be pretty tough on that spec though, sometimes, to get the FULL discount, they even want any glass in the garage door to be impact rated.

The other difficult part is not many local companies sell sliding glass doors that are Impact rated, and the only ones I've seen have been double pane. (The inner pane is laminated w/lexan).
I just had two Pella vinyl sliding doors installed, to the tune of $7000.00! They were behind aluminum shutters, so passed with the inspector. 35 mph wind rated frame. AND he checked that EVERY hole provided by the manufacturer had a screw in it!
 
I have 2 different double pane windows with that issue.

For the windows, there are company who comes, measure and make the replacement.
Then replace the fogging one.
 
Double pane replacement glass IS available. I did two side windows when I lived in Ohio, no issues. Not sure about impact glass though.
 
I do know that double pane garage door windows and building windows can be replaced as a glass-only unit - sealed glass from the factory OR aftermarket that fits into the garage door or window frame.

Large French doors might be a different story. Replacement glass might only be available from the manufacturer, unless they are standard generic sizes? I was told that door glass that a child (or anyone) could fall through has to be different (tempered/safety glass?) or plastic that won't break in a way that would stab someone. "Told", not verified.

Double panes are not only sealed, but also contain gas of some type, so I have been told. This place claims they can replace double pane French door glass: https://glassdoctor.com/expert-tips/all-about-glass-doors/french-door-replacement-glass

LOL, my in-house workplace window guy tells me my account will be charged if I request glass replacement due to fogging, but is free if a lawn mower stone breaks the window. I hate those lawn stones!
 
Originally Posted by JohnG
You guys are hosed. There is much more to getting hurricane rated doors than just the glass. Any Florida inspector will want to see the manufacturers certification for that specific door.


The original glass is simply tempered glass. It's not impact resistant. I have steel hurricane panels that cover all the doors. Replacing the glass with tempered glass would be 100% OK. I'm not required to upgrade for a simple repair.

Also of note, the pane sizes in my doors are uncommon, or at least, not the same as current stuff. I can't go out and purchase drop in panes from another manufacturer.


I plan on doing the work myself. Remember, I replace windows in aircraft with regularity. This is an order of magnitude easier. I'm thinking a single 3/8 inch pane would be sufficient. I'll bet Low-E glass would be just as efficient. NOTE: My windows are Low-E but my doors are not.
 
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Quote
Large French doors might be a different story. Replacement glass might only be available from the manufacturer, unless they are standard generic sizes? I was told that door glass that a child (or anyone) could fall through has to be different (tempered/safety glass?) or plastic that won't break in a way that would stab someone. "Told", not verified.


I forgot about the glass being tempered, but yes, this is most likely the reason that they are NOT Impact Resisitant (Laminated w/Lexan). Maybe more correctly, Hurricane Rated glass.
 
Wow, you fellows have a different set of window issues down there in hurricane country!

Internal fogging on sealed dual- and tri-pane windows is common here. There are companies that do a fix without replacing the window. I'm told they install a one-way valve that allows the moist air to migrate out (as it expands with heat) but does not allow new air back in. They claim 50% cost reduction compared to full replacement. Most of the cost would be the labour involved in removing the trim, removing the window itself, and reinstalling the window and trim. I would bet that it would be very cheap to install the valve only in a sliding door.

I'm guessing this company uses the same technique:

https://winnipeg.windowmedics.com/defog/
 
Originally Posted by Cujet


The original glass is simply tempered glass. It's not impact resistant. I have steel hurricane panels that cover all the doors. Replacing the glass with tempered glass would be 100% OK. I'm not required to upgrade for a simple repair.

Also of note, the pane sizes in my doors are uncommon, or at least, not the same as current stuff. I can't go out and purchase drop in panes from another manufacturer.


I plan on doing the work myself. Remember, I replace windows in aircraft with regularity. This is an order of magnitude easier. I'm thinking a single 3/8 inch pane would be sufficient. I'll bet Low-E glass would be just as efficient. NOTE: My windows are Low-E but my doors are not.


OK, but it's double pane, right?? So a single pane will conduct more heat through it, which also means it will be much more prone to being wet with the Florida humidity. That means more rust in the door, and shorter rest of life.

If you can live with that (maybe paint/rustproof the inside of the door where water might accumulate?), then it might be worth a shot. I dont quite get how you would seal it into place, but I suspect you have the experience to figure it out.
 
I'm still missing something here. If the original is double pane with fogging between, why won't replacement double pane glass fit? Plenty of companies make that....just not Hurricane rated.
 
Originally Posted by Cujet
[q I'm thinking a single 3/8 inch pane would be sufficient. I'll bet Low-E glass would be just as efficient.


Might want to check what a 3/8" pane that size would weigh. 3/8" glass is roughly 5 lbs/sq ft. (.091 lb/sq in.) Will your hinges hold it?
 
Replaced 3 panes of double pane regular glass. Brought the panes to a local glass company and they duplicated the panes in size and depth and gas filled. Been great for 10 years now.
Is that not possible with these panes?
 
Originally Posted by Danno
Replaced 3 panes of double pane regular glass. Brought the panes to a local glass company and they duplicated the panes in size and depth and gas filled. Been great for 10 years now.
Is that not possible with these panes?


Yes, it's possible and the cost is not too far out of this world. However, it would be really nice to completely avoid the risk of fogging.



Originally Posted by AZjeff
Might want to check what a 3/8" pane that size would weigh. 3/8" glass is roughly 5 lbs/sq ft. (.091 lb/sq in.) Will your hinges hold it?


No problem with the weight. 2ea 3/16th inch panes weigh exactly the same as one 3/8th inch plate. These doors are industrial tough anyway, not lightweight stuff.
 
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I've seen the local glass guy at the auto glass repair shop fix those types of windows. They normally use Argon gas which is inert so you don't get the fogging. The fogging is due to the seal being broken. Very common around here on older glass. His fix was to take one glass pane out and inside the window, he'd slip in a tube of silica desiccants so that once he sealed it up again it would absorb the moisture in the air. I saw him slip in a tube right underneath the frame of the window so you didn't actually see the silica. No moisture means you won't get the fogging. According to home inspectors, it's just considered a cosmetic failure, a broken seal doesn't really affect the energy efficiency that much, still better than single pane.
 
Broken Seal - can you contact the manufacturer? they may have a lifetime warranty :),
there are some shop who will reseal them, might not be cost effective,
I have one in my guest bedroom with a cracked glass on the inside that has fogged up.
 
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