Glazing

[nearlythere]

I have come across a few cases where pyro glazing elements have a "whiting/greying" spreading across the glass from the edges.
I could post a pic if I knew how to do it.
It is not on the glass surface.

Anyone have any idea what is happening?

if so has it effected the FR or insulating qualities of the glass?

Thanks

[Tom Sutton]

Normally clear but in the event of fire, Pilkington Pyrodur? turns opaque providing both the integrity requirements of a barrier to hot gases and flames. Could it be this glazing gone faulty?

[nearlythere]

Normally clear but in the event of fire, Pilkington Pyrodur? turns opaque providing both the integrity requirements of a barrier to hot gases and flames. Could it be this glazing gone faulty?

Found it in two sites now with around 6 per site. Not all elements have gone funny. An obvious fault but has it effected the glass?

[kurnal]

As far as I am aware it's usually incorrect installation technique or bedding materials allowing damp to penetrate into the core of the laminated glazing.

[nearlythere]

Thanks for comments so far.

Anyone know someone in the FR glazing industry?

[wee brian]

Sometimes its just that the seal on the glassing unit has leaked - just annouying really

If its glass with an intumescent layer then water can get into the edge and cause discoulouration - this might be a problem - seek expert advice.

[nearlythere]

Sometimes its just that the seal on the glassing unit has leaked - just annouying really

If its glass with an intumescent layer then water can get into the edge and cause discoulouration - this might be a problem - seek expert advice.

Thanks Weebee.

[Fishy]

As others have said, sounds like moisture ingress to me.  The glass should normally have a manufacturer's name etched on it so I'd contact them to see whether it might compromise the fire performance of the glass.

[Gasmeter]

I came across this problem in  modern student accommodation blocks, the manufacturer, Pilkington, informed me that it was most likely that the glass had been stored in damp conditions prior to being fitted and would not affect it's performance.