Are uPVC window knock-ons universal?

[phatboy]

Hi,

I managed to pick up a nearly new FREE window that will almost fit my garage.

110mm too narrow, 80mm too short from outside. Inside is a bit less.

I will add a stub sill then 50mm on top, and 50mm each side I think.

But... are the knock-on bits universal, or does the fit vary by extruder?

Thanks!

 

[ronniecabers]

Fit usually vary from extruder to extruder , BUT you could just turn them round and screw them on , making sure you have a bead of silicone on the faces where they meet

 

[phatboy]

Thanks. I saw Gazman recommend a while back to use timber, and then cover with plastic trim. I think that might be the way to go!

 

[Gazman16]

3x2 tantalized is fine. Not tight to the wall though or at least separated by a bit of DPC if you want it to last

 

[phatboy]

3x2 tantalized is fine. Not tight to the wall though or at least separated by a bit of DPC if you want it to last

Thanks, 50mm tan timber is actually about 45mm from my supplier after planing, so Ill fit a 3mm packer between wall and timber, and then a 2mm between timber and window, unless I can get it all perfect, and have 5mm against the wall.

 

[Gazman16]

Its just so the timber is not in permanent contact with damp bricks/walls as it wouldn't last very long that way. Tightly screwed to the window is fine.
Preferably some nice straight wood.