Water coming in around upvc window

20 Mar 2004
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United Kingdom
As I type I have water dripping onto my kitchen window ledge from around the top edge of a uPVC window.
We thought we had resolved this problem having found a crack in the render, sealed it, and a crack in the mastic around the window and sealed that. Apparently not.

The render is not "blown" from the wall as far as I can tell (not hollow sounding when tapped).

There is a window directly above the one with the leak (on the floor above) and that has no problem.

The wall around the leaking window is damp/mouldy (been leaking for some time without being noticed too much I suspect and now got worse).

Can anyone advise me ...

a) What might be the cause
b) What sort of skill I should look for to come and help me identify and fix the problem (renderer, builder, bricky, etc)

Thanks in advance
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a builder should be able to remedy this!.

it sounds like the window above is causing the problem...........i would check that again.

if theres water ingress from the upstairs window it travels down the cavity lands on the lintel then tracks in entering through the reveals of the window.
A builder (who was recommended to us) has visted and recommended a cavity tray be fitted.

This, it seems to me, simply diverts the problem water rather than solving the ingress itself.

Any thoughts?

The wall has a short (about 10 ft) area of guttering at the top, could it be that the felt is not forcing the water to the gutter? Would a roofer be best to check this (I would not know what to look for and it's a bl**dy long way up)
Have you checked the sill directly above? does it have a drip? if not the water could be tracking back into the wall

Do you notice the problem in driving rain only?

Sounds like (like me) you have separate lintels for external and internal leafs.

A cavity tray, or a catnic lintel will help divert any water out to the external leaf.
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If you look up the wall towards the gutter you should not see daylight between gutter and roof , if you can then rain can bypass the gutter.

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