Should my new double glazing windows bend???

cjaxx77

We have just had new double glazing installed and upon cleaning the lounge window i noticed that the pane palpably bends inwards!!! I cant remember ever noticing this on my old windows. It also happens in the bedroom windows, but not in the side or bathroom windows where the surface areas is smaller.

I would have thought that due to the cavity being filled with argon the pressure inside wouldn't allow for any movement.

We are concerned that this is just another nail in the coffin of disappointment and stress we have endured during our poor installation.

Can anybody shed light on this please?

Ruski

Large panes will always 'give' so not a problem.
Argon filled replaces air - it is not under pressure, just atmospheric.

HTH

Russ

cjaxx77

They didn't specify the thickness. What is the legal minimum?

cjaxx77

Hi Russ

I can't remember my old windows ever 'giving' hence my concern, but they were 25 years old so just filled with air? So, your explanation about argon fits.

I was thinking that the pressure between the two panes would be higher due to argon being heavier than gas, thus pushing the panes out!

I've got the manager of the company visiting me at four so i want and need to be armed with the right knowledge!!!

Furts

Do you have any of the stickers which were on the sealed units when they were installed. (I am assuming you checked the windows were installed the correct way round, then you removed the labels?). If so, this will give the glass thickness, overall unit thickness and details of Low E coating.

Flexing is not unusual, assuming the windows are pvcu. If they are pvcu consider what this product is - hollow section lightweight plastic, with reinforcement put in certain circumstances. Basically, it is an over hyped, low cost, flimsy product. This is not condemning it - I have them in my home. But I accept they are a functional necessity - not a "home improvement" as some of the large companies would like me to believe.

I am assuming you mean the windows flex towards the outside of your house? Assuming your windows are internally beaded might it be the sash that is flexing, or the frames have not been adequately fixed up the window reveals? Over to you on this.

As an aside, were the windows FENSA or Building Control signed off?

Plus, were they manufactured and installed by reputable companies?

cjaxx77

We were out during the installation and my father-in-law house sat. The only sticker i've seen is on the fanlight as they are yet to fit that. Its a 4mm by 4mm with a upper case E which i'm guessing is the low E coating you mention.

It is definitely the glass which is flexing, with both inside and outside panes affected.

They're FENSA approved and as long as i know the flexing is normal for my pvcu windows i can rest assured.

The fact that the old windows had no flex has caused our concerns.

How will these panes affect the rating of the windows?

Furts

cjaxx77 wrote: »

We were out during the installation and my father-in-law house sat. The only sticker i've seen is on the fanlight as they are yet to fit that. Its a 4mm by 4mm with a upper case E which i'm guessing is the low E coating you mention.

It is definitely the glass which is flexing, with both inside and outside panes affected.

They're FENSA approved and as long as i know the flexing is normal for my pvcu windows i can rest assured.

The fact that the old windows had no flex has caused our concerns.

How will these panes affect the rating of the windows?

Hi cjaxx77. Hopefully you will retrieve this before your 4.00 meeting!

It is all relative, I do not want to mislead you on flexing. No pvcu window will match a timber window in this respect.

Pvcu windows are cheap and nasty, but I like many millions, have them installed. A difference perhaps with mine, is I specified the profile, the glazing, the fabricator, the installer then watched the fitting like a hawk. This was not underhand, all parties knew this in advance. None raised any concerns.

I went the extra stage not normally undertaken - I paid an extra sum on top of the fitting quote to receive proper fitting, as opposed to standard fitting as given to all retail/ordinary consumers.

Despite this my windows are not perfect, but for the price, and accepting they are only windows, they are acceptable.

They are big, and on checking a few minutes ago, none of them flex as you describe. But I have not witnessed your flexing.

Your 4mm glass sounds OK, but it does come down to my unanswered question about "is a company reputable?" If you wish to name names it could help, or it might shame your installer into action?

cjaxx77

We had three quotes and this company - Conservatory & Door Outlet, Mirfield, West Yorkshire gave us the most competitive quote.

When we mentioned them to Coral during their quote the rep said they were good and that he knew one of the fitters so we opted for them.

We can't find many testimonials on the net other than the ones on their website.

I'll mention my concerns to the manager during our meeting and see if anything he says is congruent with info ive found on the net

greyteam1959

Well I for one don't like the sound of this one little bit !!
How big are the windows ???
Sounds to me as thought they have used 4mm glass on a big window when they should have used 6mm.
I have loads of large double glazed windows & I can tell you that the glass does NOT flex at all.
Sounds to me like somebody has been cutting corners !!

cjaxx77

He's just left. Told me its not unusual to have a flex in toughened glass which is used for the main panes. As a windows layman he could tell me anything!

I'm going to seek some further info to suppliment the useful info and advice you have all offered in this forum.

Many thanks to you all

Jaynne

The argon pressure vs air is not going to make a difference - gas unlike liquid is very compressible it just sounds like thin glass to me but being also a window layman I don't know whether that's common. Our giant glass french doors don't flex and presumably they're toughened too.