Large picture window glass flex

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familyman11
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Joined: Wed May 02, 2018 10:12 pm

Large picture window glass flex

#1 Post by familyman11 » Wed May 02, 2018 10:26 pm

I recently had most of the windows in my home replaced with Sunrise custom vinyl windows. We're really pleased with these windows so far. However, we noticed that in the large picture window in the master bath (it's tempered glass) there is whole lot of flex to the glass. I can push in the middle of the glass and it flexes in and then pops out.
It's roughly a 5' x 4' window and I'd guess it's flexing around a half inch or so. It flexes so much that it shakes the grids between the glass when I let go. Is this normal? The installers thought it seemed a bit excessive. The large picture window in our kitchen that's similar in size (not tempered, no grids) has a minimal amount of flex, nothing like the bathroom window. I'm going to speak with the owner of the company that did the install, but I'd appreciate thoughts from this group. My concern is that with all that flexing, it's going to pop the seal or we'll lose the argon gas or something. Thanks in advance!

TheWindowNerd
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Re: Large picture window glass flex

#2 Post by TheWindowNerd » Fri May 04, 2018 5:01 am

I would not be worried about it. Just do not lean on the glass.
No warranty issues. I do not know how it could flex 1/2".
At 7/8" thick OD, 1/8" minimum lite thickness and GBG, I would be surprised if it is a 1/4" flex.

masterext
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Re: Large picture window glass flex

#3 Post by masterext » Fri May 04, 2018 2:09 pm

I agree. You can always get some deflection ( flex) but not a 1/2”. I would relax, not so sure thats an issue. As my buddy said above, a 1/4” would even be a lot.

familyman11
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Re: Large picture window glass flex

#4 Post by familyman11 » Fri May 04, 2018 3:05 pm

Thanks so much for the replies. I appreciate all the advice that is offered on this board. I referenced it quite a bit when 'shopping' for replacement windows. We felt good about it, but this just seems off. The 1/2" is an exaggeration, but I figured a video might help. I wasn't able to attach, but below is a link for it. Spoke with the company that did the installation as well and he has his Sunrise rep checking with one of their engineers. I'll be sure to update the post with that info. Thanks again to all willing to share their thoughts.

https://www.dropbox.com/s/3e78gsz9ej8c0 ... 3.mp4?dl=0

masterext
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Re: Large picture window glass flex

#5 Post by masterext » Fri May 04, 2018 8:40 pm

After seeing thay video, i agree with you. It almost appears that the glass is just sitting in the sash.

familyman11
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Re: Large picture window glass flex

#6 Post by familyman11 » Mon May 07, 2018 2:21 pm

Thanks masterext, I appreciate you taking a look! Over the weekend I received an email from the installer who had reached out to a Sunrise engineer. Their explanation is that 'glass used in the tempered unit is thinner'. They provided an example for 18 sq ft of glass, non-tempered would use 3.9mm thick glass, but tempered would be 3.0mm glass. I'm still not convinced though and not sure how to address this. I'm going to go back to the company that did the install and see what else they'll say, but not sure I'll get very far.

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Windows on Washington
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Re: Large picture window glass flex

#7 Post by Windows on Washington » Mon May 07, 2018 4:47 pm

Love the lake view. That is weird.

Let me share with this my friend that is a glazing engineer and see what he says.

Paging Oberon.....

toddinmn
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Re: Large picture window glass flex

#8 Post by toddinmn » Tue May 08, 2018 6:56 am

It seems odd they would use thinner glass for tempered, most tend to go heavier if anything. Perhaps ask them hat the tolerance is for deflection in there glass packs.

familyman11
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Re: Large picture window glass flex

#9 Post by familyman11 » Fri May 11, 2018 8:38 am

Thanks Todd, I've requested that from Sunrise and will update once I hear back. My installer also shared information that tempered glass is more flexible, however I'm still wanting a clearer answer.

toddinmn
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Re: Large picture window glass flex

#10 Post by toddinmn » Fri May 11, 2018 9:13 am

The elasticity of Glass does not change with tempering, it flexes the same amount as annealed glass if the thickness is the same. I’m no expert on glass but it took me less then a minute to google the answer, hate it when people try to blow smoke where it doesn’t belong.

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