eLuSiVeMiTe
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Eh. The bit with the single hole screws into the upvc frame the lugs stop it rotating . You fix through the rest into the inner skin of the wall.
- Thread starter Barking Mat
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eLuSiVeMiTe
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willie.macleod
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Expanding foam is PU!
Lost count of the number of tins I used building my ICF house. It's not a bodge using the correct stuff, it gives you a far better installation than simply screwing the window and trying to seal it with a mastic or silicon. By all means use a mechanical fixing as well if you wish but don't write off all foam jobs as bodges. Use low expansion foam, a spray bottle to damp the surfaces, make sure the window is adequately supported before you foam it and use a proper gun with suitable nozzle, don't try it with a disposable tin.
eLuSiVeMiTe
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These and glazing Packers are handy to have when fitting too.
https://www.ffx.co.uk/tools/product...tiQmcw-gD1akywIMLEdt8BXkF42oDio4aAo0cEALw_wcB
https://www.ffx.co.uk/tools/product...tiQmcw-gD1akywIMLEdt8BXkF42oDio4aAo0cEALw_wcB
Ok, I see, fine if your window reveales are bare and unfinished. What stops them moving up and down?
I think they have their place, but don't suit every need.
I will say, every one of the masonry screws I put in on the weekend worked, even the ones up into the catnic lintels, even if they took a while to get done.
Edit to add - you need a steel drill to get through these - I used a battery drill for this, with a 110V sds for the masonry.
eLuSiVeMiTe
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Ones I've used in the past were fixed to the extrusion and didn't slide.
Barking Mat
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Thank you.
Barking Mat
Cuddler of hedgehogs.
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No.
Pu polyurethane is like mastic , expanding foam is like expanding foam unless I'm a complete drunken f#ckwit.
Barking Mat
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Which I could be, let's not forget that, it's late...
willie.macleod
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They are both polyurethane, one is in sealant form the other is a foam. The foam version can be used to give structural fixing, insulating and airtightness properties when fitting windows/doors at a reasonable cost. The sealant version really isn't as well suited for installing house windows/doors and while you can no doubt use it to help seal gaps it is a pretty expensive way to do what a cheap tube of mastic can do at a fraction of the cost.
Barking Mat
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I stand corrected.
I will debate this with you tomorrow, when I'm more sober.
They seem like two completely different products to me.
But I'm not sober, so I'll give you the benefit of the doubt.
Thanks for the input. Anyway.
I'm off to to play with my babies.
HughF
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Unless you have checked reveals, how else are you going to get an airtight join between some rough old masonry opening and the completely flat pvc window? Yes you could use compriband, yes you could tape the inside of the window back to cavity closer prior to putting the internal reveals on, but low expansion foam is more air tight and helps with the mechanicals.
One thing you absolutely do not want to do is rely on the external beading to provide your air movement prevention. My Mrs had new windows fitted about 9 years ago, inch gap all the way round, no foam... The roaring 40mph south westerlys whistle through all winter. I'm going to pull the beads off next spring and foam them all up.
Barking Mat
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Thanks Hugh for the advice.
HughF
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I'd definitely recommend using PU/Sikaflex instead of some slightly junk silicone. Yes it's more expensive, but at least you know its not going to just peel off the window in 3 years time.
As for foam, low expansion is what you want.
As for foam, low expansion is what you want.
Morrisman
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Some friends who live in France had that exact problem when they built a large enclosed porch on their house: checked the available sizes...carefully measured the holes they made.....ordered the windows.... windows arrive a month later.....about an inch too big all round.
The supplier just told them to bring them back.... about a 200 mile round trip....and he would have a look at them. To save time and effort and money they hacked out the woodwork to take the oversize windows.
mike os
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pu foam for closing gaps and sealing, not fixing, or at least not the only fixing, helps stiffen the frames up
straps are great if you are planning on redecorating, screw to side of window and chop the plaster off inside, screw to wall and repair
straps are great if you are planning on redecorating, screw to side of window and chop the plaster off inside, screw to wall and repair
pedrobedro
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I was fitting ours up to the old plaster in the reveal so I didn't want to chop out. I've seen them fitted just using builder's band cut into sections for a cheap alternative to buying something dedicated to the job. Ours are all into the brick with bolts and spacers to stop the frame bending
HughF
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same with ours... with a one inch gap all round and no foam... bloody cowboys, what is it with the UPVc industry
chrisg3103
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Not condoning using solely foam as a fixing, but have you tried ripping put something that has been foamed in? Its in there good! Foam expands into every nook and cranny on brickwork and sticks like the proverbial.
Can even get expanding foam post fixings for fences...
For the record I used concrete screws where I could and fixing straps where I couldn't when putting in my windows. But the foam certainly took and flex out the frame
Can even get expanding foam post fixings for fences...
For the record I used concrete screws where I could and fixing straps where I couldn't when putting in my windows. But the foam certainly took and flex out the frame
the snooper
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You are supposed to measure the aperture horizontally and vertically in three places then allow space, think it was minus 10mm in both Directions, the space allows you to get your frames in level if the brickwork is out using packers to make it a tight fit, drill and fix through the Packers so as not to distort the frame then I used spray foam which as said earlier stiffens the frames no end
Ps, use the smallest of the 3 measurements minus the 10mm to order your frame
Ps, use the smallest of the 3 measurements minus the 10mm to order your frame
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