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Water leak under uPVC window frame

Postby pulpkiwi » Mon Jul 27, 2020 11:20 am

Hi All

I've traced a damp issue to water ingress underneath a double glazed uPVC window unit. The unit sits directly on top of masonry tiles which are pointing downwards to create a window ledge (just re-done the mortar on them, needs painting). See pics.
The window sashes have weep holes in the frame below them which drain outwards correctly.

My question is, do uPVC FRAMES have drainage holes in the bottom? If so, that would explain the issue as the gap between the tiles and frame on the outside is sealed, so water can't escape. I wouldn't expect frames to have drainage though, as water shouldn't be able to get into it?

Any help would be much appreciated. Once I've sorted this leak I have a long list of jobs to make good the ruined wall below it, this has probably been going on for decades :(
Internal view. Slight water ingress below window, on top of tiles
External view. Gap between frame and tiles is sealed.
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Simply Build It

Postby stoneyboy » Mon Jul 27, 2020 9:40 pm

Hi pulpkiwi
Yes your frame and cill should have weep holes in them. Also your external cill tiles should not extend to the inside, they should stop under the frame.
Regards S
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