PVCu expansion - Seriously?

2 Sep 2019
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United Kingdom

Quick question for any window fitters. I got this card posted through my letterbox after complaining about being unable to close our front door on a new build (black uPVC). This first occured back in march when it was 14c outside and now happens basically daily between 9am and 10pm if we open the door.

It states the pvc will expand upto 2.4cm and it's perfectly natural and once the sun sets I can basically shut my door again. In extreme circumstances I can damp it down with a towel....

Is this correct and does that alleviate them from any responsibility as a problem that needs attention.

I'm a automotive manufacturer machine designer at the moment but trained degree wise as a vehicle designer, if in either role I allowed a vehicle to leave the factory where you couldnt shut an open door in direct sunlight I would expect a huge recall and to be sacked, how have they managed to make this **** a standard?

Honestly shocked at the gall of suggesting it's ok that a door cant shut. It's literally it's only function.
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Apparently you're not allowed to get the glass wet either! Bit of a bummer when it rains :).
Lol didnt think of that.

I honestly cant believe they sell this stuff with caveats like that.

It's basically not fit for purpose as a material
Well then so is wood because it swells, shrinks and rots, steel because it rusts, aluminium because it corrodes. Unfortunately pvc IS going to expand in the heat, especially south facing and during heatwaves like we are experiencing at the moment, dark colour just make it worse, it will of course also shrink when its cold. That said there is a degree of tolerance built in to allow for expansion and contraction which should still allow the door/window to function even if slightly more difficult, in my 25 years in double glazing fitting and repairing I've never come across a manufacturer, supplier or fitter that has gone as far as to say in the hot weather your door won't work
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Material degradation is not the same as incorrect functionality though. This is more akin to using a chocolate fire guard than worrying about corrosion.

If it only occured at 40 degrees when south facing that would be an extreme scenario and fair enough. But this is north facing, 14 degrees, 9am in the morning and I'm being told it's normal to not be able to shut my door because the material expands lol
Black uPVC is the worst. We all know how black absorbs infra red/heat - anyone with a black car knows how hot it can get when standing. Coefficient of thermal expansion of uPVC is 0.06-0.08 mm/degree/metre so a typical 800mm wide door between winter (say 0 degrees) and high summer (say 40 degrees surface temperature (as it's black)) = 0.07x0.8x40 = 2.24 mm. You should be able to set the door up to accommodate that variation, bearing in mind the uPVC frame will also move a bit.

Edit - and you are quite right. The card is BS, and a door you can't open during the day is undeniably not fit fit purpose, and you can go after them to get it sorted.
I agree that note is BS, yes it will expand theres no getting away from that, even steel reinforced frames, the steel just expands at its own rate but theres tolerances to allow for that, my guess the door slab has been set up too close to frame normally for ease of use ironically(when its cold), when setting doors up in the colder months you have to find that happy medium, sometimes guess work but most of the time experience but on a north facing door thats not going to get mega hot if at all then you can find that sweet spot close to factory settings
Yea the door was fitted just before Christmas, to tight tolerances no doubt.

Had a second opinion have a look at it and they have suggested the frame is bowed down the vertical lengths so looks like a refit is in order
they have suggested the frame is bowed down the vertical lengths

If it was installed tight in the freeze of winter, quite likely the sides have bowed because they have tried to expand and can't. Yes, a refit required.
Looks that way, is there any mechanical fixings along each length, probably looking at 4 down each side, if no visible fixings then its fitted on straps which will be hidden under the plaster reveals now, to remove and refit will involve a degree of plaster damage, another possibility is the frame has been foamed in just for thermal reasons and the foam has bowed the sides in, it does have the strength to do that believe it or not
Ah then it might be possible to remove any packers behind the frame and nip the screws up to remove the bow however if its tight in the height then no amount of tightening will remove the bow, also risk cracking the pvc, I'd insist on getting it refitted
Yea it's part of a new build and we only moved in in January so insisting on everything at the mo whilst it's not costing us

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