Not sealing sill to window?

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We had a load of new windows fitted last year, with face drainage.

We had an issue with water marks below one of the windows last year (Big post on here about it), and the contracts manager later said the sill ends may not have been sealed properly and then back tracked and said it was rising damp!

We had 1 final windows fitted by the same company, and same fitter last week. I asked him if the sill ends should be sealed to the UPVC windows when installed, and he said it's not something he ever did. I noticed he didn't seal the sill to the window at all, just fitted it on top then screwed them together with some short screws with large heads.

Should he have, and do I have more problems awaiting me?!

Thanks!
 
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It's best practice to seal the sill to the window and close the ends off, the screws used were probably 'baypole screws', correct for the job, just don't over tighten them and distort the frame, best practice again though
 
Face drain with cills is a bit odd. Have you got links to your old post?
I assume bottom corners of the plaster by the window were getting wet? Common sign the window hasn't been sealed to the cill
 
Here is the link to the original thread, in the Building forum, as I first assumed it was the roof!

https://www.diynot.com/diy/threads/damp-coming-in-trying-to-find-source.496281/

The damp is actually at the bottom of the wall, but the likely reasons for thata re in the other thread - external insulation and the positioning of the windows.

It was indeed baypole screws used to connect the sill and window.

Thanks
Tim
 
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That is some very odd damp patch's, Not really typical of the cill not having been sealed.
Its a bit messy and a pain in the butt but I would be tempted to remove a brick/block on the internal wall where that big damp patch is. I suspect a blocked cavity/bridged DPC.
 
Hi, the house is solid blockwork so no cavity. The windows are pushed right out to the edge of the block work, so they are inline with the external insulation so as to prevent any cold bridging.

My thought was water could be leaving the end of the sill, and running down the outside of the wall between EWI and pebbledash, and it comes through there as that's where the original plinth detail is, and so the water cannot go down past that.
 

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