Internal Window Cracked due to Temperature Change?

paperclap

Hi all,

So, our internal window panel cracked today.

I’m assuming it is due to the fascia/soffit creating a shadow line across the panel, creating a temperature change between two sides. Weird though, as it’s only been around 16 degrees today!

But hey, it’s happened.

Does anyone know the best place to buy replacement window panels?

I’m planning on popping out the trim, and replacing it myself. I’m assuming both panels will need to be replaced as a single unit, rather than one window panel individually?

Thanks!

FreeBear

It will be a sealed unit, so you won't get a choice but to replace both sheets of glass. Pop the trims out and carefully measure both the height & width and the thickness of the unit. Do a local search for glazing suppliers, and you'll soon find one that can make up a replacement fairly quickly. As long as the window cill is at least 800mm from the floor, you don't need toughened glass.

The trims can be a bit of a pig to remove, but if you are careful, a paint scraper can be tapped in between frame & trim - Start from the middle of the longest side. When putting the trims back, use a rubber mallet (gentle taps) and try not to hit the glass. If in doubt, see if you have a local window doctor.

greenface2

could be thermal stress . could have been damaged internal with flex in the recent winds and shelled then broken recently . could be sat bad on packers but that doesn't look like it is . Go to your local DG suppliers . popping it out first would give you the correct size inc thickness of the unit . internall glazed co extruded gasket should be simple 

TELLIT01

You will certainly save some money by doing the work yourself BUT a glazier will be able to get accurate sizing without removing the pane to measure it.  If you have to remove it to get measurements are you confident that the glass won't break and that you will be able to put the pane back in temporarily.  You're unlikely to be able to walk in and get a new pane from stock.

paperclap

Thanks all!

FreeBear, our window sills are quite low. Not measured, as measuring tape is in the blasted shed! Why would toughened glass be required for lower window sills?

A few of our windows are blown throughout the house. Wondering, is it actually worth (the money) replacing this cracked unit? Looks unsightly, sure. But, is it likely to crack further (and therefore be a danger/hazard?)

FreeBear

laurencewhymark said: Why would toughened glass be required for lower window sills?

Building regs.

Safety glass (either toughened or laminated) is required on all doors & windows below a certain height. Should you or a small child trip and break the glass, injuries will be minimal.

You could leave the current unit for a while. The crack will probably grow across the full width, but it won't explode and send shards of glass flying. Still wants replacing before the winter comes round again.

greyteam1959

If you going to do the job yourself be aware that popping the glazing beads out is not as easy as it sounds to the inexperienced.
If you are going to DIY the job buy a new unit with toughened glass.
A few £'s more but you are less likely to break it during installation.
Another tip re sizing.
Take the panel out & measure the TOTAL thickness in mm plus of course the length & width of the panel.

TELLIT01

We had a blown unit replaced and the guy who did it had a devil of a job getting the unit out because it had been in place so long.  He did manage but it took him ages.

paperclap

Have just measured the floor to the window seal and it’s 760mm… so there you go!

If it’s a few pennies more, I’d probably go for the toughened glass.

greyteam1959, do you mean measure the depth of the unit as a whole? E.g. from the outside of the glass to the outside of the other glass panel?

Bendy_House

Yes. Put simply, you want the same size in all three dimensions.
There must be YouTube vids to guide this, but essentially you first determine whether the removable beads are on the outside or in, most likely the latter.
The beads have flexible rubber blades which seal against the glass. For the beads to be removed, they first need pressing in further against the glass, and then they can be prised away sideways. The rubber will likely be partly stuck to the glass so won't want to slip as they'd need to, so useful first step would be to spray soapy water on them, and slide summat thin and smooth between the rubber and the glass - it mustn't damage/cut/tear the rubber, tho'. An old credit card, say, with smoothed-off edges? A strip from the side of a plastic milk 'bottle'? Get it in there, wet it, and slip it all around so the rubber blades are free slip slip on the glass - you should then be able to press the trims inwards and disengage them.
The glass unit MIGHT be held in with double-sided tape, but - if the beads are internal type - most likely not. So, one person preventing it from falling in (gloves and goggles...), and another pushing gently and evenly from the outside. If you take the whole unit to a DG cove, they'll copy it - no need for you to measure.
Why did this pane fail? It shouldn't do so from thermal shock, just shouldn't. UNLESS something was preventing it from moving, exp and contract. So, once the beads are off, look all around the perimeter of the unit to see if it's binding or tight anywhere - there should be good clearance all around. Another possibility is that the window frame is twisted, and this should be detectable once the unit is loose - push it back into place and see if it touches the outer beadings at the same time all around?
Once you've cut your teeth, and hopefully nothing else, on this window, you'll know whether you'll want to do the other failed units! Bear in mind that a misted unit is really just a cosmetic issue, and not thermal.

ComicGeek

Bendy_House said:

Bear in mind that a misted unit is really just a cosmetic issue, and not thermal.

Misting means that the seal between the glazing panes has failed - it is certainly a thermal issue, as the benefit of the previously sealed double glazed unit is significantly reduced, particularly if it was an argon filled unit. Not just in winter, it's also noticeable in the summer as it won't be dealing with solar heat gains or warmer temperatures as well as before.