Strange condensation pattern on new window

Joined
14 Nov 2014
Messages
1,184
Reaction score
263
Country
United Kingdom
Argon gas wasn't normally used for this purpose, it is a heat retention gas , yes it's heavier than air and yes it will sink and yes it disappears within 3 years ( so much for energy rated windows eh? Lol)
My first suspicion here is that they have used 4mm glass for that sealed unit. A unit of that size would be much better in 6mm tough glass. Yes the airgap is smaller but 6mm glass doesn't deflect as much. You should not have a cold spot in the centre of the unit like that. Personally I have never seen the method Crank suggested for the sealing of the unit, and that is probably due to us using 6mm glass in big sealed units such as this.
There is an industry standard at which point 6mm tough should be used ...as follows . If both dimensions are over 1300mm and also sealed units bigger than the following sizes 1200x2000, 1100x2200, 1000x2700, 900x3000. And any unit over 2.4m3
Those units look bigger than 1300x1300 to me , and looking at the spacer bar size it looks like a 20mm air gap, which would mean if 6mm glass was used the sealed unit will measure 32mm thick , most Ali and pvc double glazed systems only use a 28mm unit , which means the glass can only be 4mm thick. I may be completely wrong as I'm going on what I can see in the picture
 
Sponsored Links
Joined
1 Dec 2009
Messages
5,236
Reaction score
1,038
Location
South Yorkshire
Country
Barbados
Ronnie I regularly saw it when I worked for Saint Gobain Solaglas down at Binley 1 and 2 in Coventry
 
Joined
3 Dec 2019
Messages
21
Reaction score
1
Country
United Kingdom
Hi, I’ve been told the glass is 4mm thick and the spacer is 20mm. The person who sold and installed it has said this means the actual gap between panes is 16mm.
I’ve actually measured the ‘bow’ on the outside pane... it’s bowed by 13mm in the middle. So surely this means the glass panes are 3mm apart in the centre? Which is why we’re getting a cold spot there...
That seems a lot to have bowed by to me? Do you know how much they normally bow? thanks
 
Joined
14 Nov 2014
Messages
1,184
Reaction score
263
Country
United Kingdom
Lol, I have absolutely no doubt that it is done the way you say Crank. ..just never seen it myself lol
 
Sponsored Links
Joined
14 Nov 2014
Messages
1,184
Reaction score
263
Country
United Kingdom
Can you just measure the visible glass size , width X height please? I suspect it should be 6mm glass even more now
 
Joined
1 Dec 2009
Messages
5,236
Reaction score
1,038
Location
South Yorkshire
Country
Barbados
Hi, I’ve been told the glass is 4mm thick and the spacer is 20mm. The person who sold and installed it has said this means the actual gap between panes is 16mm.
I’ve actually measured the ‘bow’ on the outside pane... it’s bowed by 13mm in the middle. So surely this means the glass panes are 3mm apart in the centre? Which is why we’re getting a cold spot there...
That seems a lot to have bowed by to me? Do you know how much they normally bow? thanks

If the glass is 4mm with a 20mm spacer(air gap) plus another 4mm of glass simple maths says its a 28mm unit, you've been told thats what it is but the person who sold and installed it says its a 16mm air gap, how can it go from a 20mm to 16mm air gap its one or the other? Now if it was a 16mm air gap it would point to it being 6mm glass as this then comes in at 28mm
 
Joined
14 Nov 2014
Messages
1,184
Reaction score
263
Country
United Kingdom
And there is more likely your problem. Both panes of glass should be 6mm tgh with a 16mm airgap. 6mm glass does not deflect as much. See my post above
 
Last edited:
Joined
14 Nov 2014
Messages
1,184
Reaction score
263
Country
United Kingdom
Crank , I can only guess whoever sold it is saying 16mm airgap as they knew that glass would move. To me , from those pictures it looks like a 20mm Silver/grey spacer bar
 
Joined
30 Jun 2008
Messages
15,506
Reaction score
1,803
Location
Suffolk
Country
United Kingdom
in which case the Argon would sink to the bottom and leave before the air. Better to inject the Argon at the bottom
H'mmm, food for thought. Maybe that's the way they do it and I got mixed up. It's about 10 years ago when it was explained to me.

Crank. I didn't realise the seal was permeable. Is that the main cause for the cells failing after a number of years?
 
Joined
1 Dec 2009
Messages
5,236
Reaction score
1,038
Location
South Yorkshire
Country
Barbados
Hard to tell from the pics whether its 16 or 20mm spacer, IF its a 16mm with 4mm glass than its a 24mm unit the absolute bare minimum you can get away with, 4mm glass in that size will deflect loads, its been sealed laying flat on a bench with the top pane sagging down, its been sealed and now its fixed into a bowed in position and I dare say in the middle the two panes are damn near close to each other, a glass area that size should have been 6mm, wind deflection calcs should have told the glass unit manufacturer that right at the start
 
Joined
14 Nov 2014
Messages
1,184
Reaction score
263
Country
United Kingdom
Conny , no it's not the main reason. Honestly there had never been a definitive reason, to many factors. Humidity levels on factory, age of dessicant, poorly glazed, badly sealed or just plain bad luck seem to be the main causes
 
Joined
14 Nov 2014
Messages
1,184
Reaction score
263
Country
United Kingdom
The supplier should be able to answer about the sealed unit make up, by looking at the paperwork or by using some of the tools available in the industry.
As I said, my suspicion is the unit is 4-20-4, but I stand to be corrected
 

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.


Are you a trade or supplier? You can create your listing free at DIYnot Local

 
Sponsored Links
Top