New double glazing units - safety glass marks, is there a front and back, u-Values...

[Oxbow16]

Hi

 

I recently had a few DG units replaced in my uPVC windows as the old ones had failed and misted.  I've noticed a couple of things that I just wanted to check...

 

1. If a window needs safety glass and the window has two units at the same height, should both units be marked as safety glass or just one?  In my case only one is.  Does that mean the other unit is not safety glass?  Or is one mark enough to say the whole window is safety glass?  Hope I'm making sense here!

 

2. Do the panes have a front and back or are they the same both ways? I was looking at the writing you get on the spacer bars and noticed it is the right way up on some panes/facing inward and upside down on others/facing outward. Is this normal or should it always point the same way?

 

3. Is there any way to tell whether a unit is standard, a-rated, or whatever? I seem to remember once seeing an installer use a gizmo to check the u-Value of our old windows. He held it up there for a couple of seconds or so and got a reading. But I can't find a tool like this and if such a thing does exist I can't imagine it would be cheap??  Any other ways to tell?  We had the option of Standard or A rated and went with the later.  I want to make sure we got it!

 

Cheers

[A_L]

I would expect every pane of safety glass to be etched with the appropriate BS EN number.

 

Only panes with a low-e or other coating would have a front/back

 

Search for 'detecting low e coatings' will give plenty of detectors for at least double glazing, not sure about triple, prices start at about £48.

Edited December 8, 2020 by A_L

[Russell griffiths]

Every pane of ours has an etching mark on it. 

 

Put a picture up, if you have two panes do they both have to be safety glass, are they side by side or one above the other. 

Edited December 8, 2020 by Russell griffiths

[craig]

Every individual pane must be marked. UK supplied glass will be kite marked. European glass will be marked with EN number generally on spacer bar sometimes on glass.

[Oz07]

Unlikely but if one is laminated perhaps the mark has forgotten to be put on. Glazing merchants I use do their own mark on laminated stuff if needed

[Oxbow16]

Many thanks for the replies.  To answer some of the questions....

 

  On 08/12/2020 at 17:49, Russell griffiths said:

if you have two panes do they both have to be safety glass, are they side by side or one above the other. 

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The two units are side by side and therefore more or less the same height so yes both need to be safety.  

 

 

  On 08/12/2020 at 15:12, A_L said:

Only panes with a low-e or other coating would have a front/back

 

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Hmm, and I'm not certain whether ours has or not.  Guess that's one of the things in question.

 

  On 08/12/2020 at 15:12, A_L said:

prices start at about £48.

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A bit much for a one time use I think.  Good to know they exist though, although seems they just detect the coating and nothing else.

 

 

 

So if every unit/pane should be marked, I'm starting to think they just forgot to make one of them safety glass.  Very annoying.  Not sure if they are laminated or not to be honest, but I'm thinking not.  Here's a close up of the kite mark:

 

 

Thanks again    

 

 

 

 

[Ian]

The safety mark on your glass is BS12150 which is the standard for toughened glass

[A_L]

@Oxbow16, is any part of the marked pane within 800mm of the floor or 300mm of a door and the other not?

 

Yes as Ian has said that is the toughened identifier. A laminate pane would also be a minimum of 6.4mm

 

There is a claim that the reflection of a flame is a different colour (bluer) from a glass surface with a low-e coating (and some you tube videos)

[Oxbow16]

Both panes are side by side and within 800mm of the floor.  I'll upload a photo in a mo....  

 

Interesting RE the flame.  I'll look that up on YT and give it a try.  Thanks for the tip.  

[Oxbow16]

Here's that pic.  Excuse the mess! 

 

 

[Conor]

  On 08/12/2020 at 20:51, Oxbow16 said:

Many thanks for the replies.  To answer some of the questions....

 

 

The two units are side by side and therefore more or less the same height so yes both need to be safety.  

 

 

 

Hmm, and I'm not certain whether ours has or not.  Guess that's one of the things in question.

 

 

A bit much for a one time use I think.  Good to know they exist though, although seems they just detect the coating and nothing else.

 

 

 

So if every unit/pane should be marked, I'm starting to think they just forgot to make one of them safety glass.  Very annoying.  Not sure if they are laminated or not to be honest, but I'm thinking not.  Here's a close up of the kite mark:

 

 

Thanks again    

 

 

 

 

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Hit the other one with a hammer and you'll know for sure of its safety glass or not