Proper installation of large triple glazed hybrid windows
Hello everyone,
Not too sure who to turn to, so some opinions would be really appreciated.
I just got my windows installed, they’re triple glazed, quite large (8’ width x 6’ height), pvc inside and alu outside. The retailer is know to be quite good quality and after sales service.
for some reason over the last couple of weeks they all seem to have settled to the point where some are hard to close.
As you can see on the photo, the frame seems compacted exactly where the shims are to support the window.
I spoke to my gc and the window retailer but they are all trying to defend themselves, naturally. I don’t really care who’s fault it is as long as we find a solution.
knowing that, I am wondering what could’ve been done differently or what can be done to correct the problem. On the day of installation, everything was perfectly square and leveled, no bending or waving at all.
From your experience, can this be avoided and what can be done from here?
Thanks in advance for your precious advices!
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Replies
Sorry I don't have an answer. But if there's an up side to this, it's that the problem is both clear and apparent, and it's expressed itself before all the trim and finish work is complete. The obvious solution (to me) is to better support the base of the windows (more shims, etc.), but I've never (ever!) installed a window like that. Good luck getting a robust and durable fix. It's a beautiful view.
Thanks for your support John! Really appreciated. We’ll try to get that straight, hopefully the performance of the window isn’t too affected!
You may be able to fix it with air shims. It would not be an immediate process, and whether the wave would disappear is not clear. but if you slowly inflated an air shim to get the bearing off those center shims you could insert new ones at appropriate spots. The one thing that may be difficult is getting them to be level with the other shims, but it would be better than the current situation.
The wavy edge makes me think the frames are not metal-reinforced and rely on the house framing and the glass itself for structural integrity. The shims might have been driven tighter than they should have been. I prefer to use metal-reinforced frames with large PVC windows.
Hello Michael, thanks for your reply.
Metal reinforced would’ve been awesome indeed, actually it’s wood.
As for the shims it’s hard to tell, the window was perfect upon installing, they really settled/compressed the pvc frame! Trying to find out but I’m starting to believe no shims should be there except for vertical frame elements.
And on a side note: PGH is awesome! Can’t recommend it enough. Make a French version so I can throw it at my construction friends face :)
The window frame is wood? Then having that kind of deflection is odd indeed. In my experience, window installation instructions usually call for shims every 12-24" along the bottom, especially for large windows, but I'm sure there are exceptions.
I'm glad you like our book! I'll let the publisher know that the world wants a French version, but don't hold your breath ;-)
Actually it’s just PVC, my bad!
The shims are in the wrong spot. They should only be under the corners and in the middle where the frame is not in the middle of the glass.
Thanks for your reply Akos!
It’s what I am starting to believe! So there should be only 3 shims for the full width of the window? Under each vertical element of the frame?
This is my thought as well. Unless the window manufacturer specifically called out shims in those spots, they should be closer to the verticals.
“So there should be only 3 shims for the full width of the window?”
Not necessarily, think of it more in terms on the glass, you want one at the corners as this is generally were the glass is bearing on the frame. Often times though, window manufacturers will call out shim locations with stickers on the glass, as sometimes they have bearing locations mid span, or at other locations. Also you would want at least 4 for a slider, as you would want to support either side of your vertical. You shouldn’t have an issue using more shims though in between, it’s more that the bearing points were not supported in your install.
Shims should definitely be under any mullions, but large windows also need intermediate shims along the sill. Otherwise they will sag over time.