Sealant to use around UPVC Double Glazing (Exterior)

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KillerHERTZ

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My flat currently has some very old UPVC double glazing, when its windy I can hear a whistling coming from the windows. After looking outside I can see that on 3 sides of the windows the sealant between the window frame and the brickwork is cracking, and half of it has already come away.

As a short term fix, what would be the best sealant to fill the gaps in until I can get replacement windows?

Thanks!
 
The wrong expanding foam I believe can bow the window, meaning you maybe worse off. I believe expanding foam for upvc has a lower force on expansion.

:)
 
If it is just sealant around the frame rather than big gaps, you need low modulus silicone

edit
fill any big gaps first.
 
Last edited:
Thanks for all the replies, can't use expanding foam as its only around a 1cm gap + it will make a visible mess. Will look through other options tho :)
 
Thanks for all the replies, can't use expanding foam as its only around a 1cm gap + it will make a visible mess. Will look through other options tho :)

If it is a 1cm gap, I would cover the gap with a 2cm wide upvc trim, stuck on to the frame with Stelmax 1961, which you could then use to seal around the trim where it abuts the brickwork.
Alternatively you could use solvent weld to stick the trim on then a low modulus mastic to point up.
 

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