Hi, I have been experiencing really bad condensation on my dormer window. I can feel a draught so I know I need to tear up the plasterboard and the interior window board to foam up any gaps. I took of the window board and noticed a bit of mould underneath. I don't know if there is water ingress or if its just the condensation causing it. There is a gap between the window frame and what looks like something I can only describe as a floor plate (grey/black colour) the window frame sits on? Is water getting through on that may be? Do I need to seal this gap up? I think silicone rather than expanding foam for this gap. Any insight would be greatly appreciated.
Window draught sealing (Edited, it's rain penetration)
- Thread starter P3UAL
- Start date
Condensation is not caused by draughts. Where do you think the water vapour causing the condensation is coming from?
Stand back and take some wider pics please, and from the outside, showing how the window is sealed to the wall top, bottom and sides, as there may be rain penetration.
Why is the wall broken or crumbling in your second picture, and where is that?
Stand back and take some wider pics please, and from the outside, showing how the window is sealed to the wall top, bottom and sides, as there may be rain penetration.
Why is the wall broken or crumbling in your second picture, and where is that?
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Why did you need to remove window board, can think of no good reason.
It can be. Condensation is caused by warm moist air hitting cold surface. Draught causes cold surface. Draught also lets in external moist air.
If moisture is coming from the outside, then the best way to deal with it is from the outside. But I think the problem is a combination of air leak from the outside and interior condensation. If you seal up all the gaps and cracks, it should make the situation better. Caulk cracks and allows travel of water.
You can have filled any gaps on window board from above.
You need good ventilation to avoid condensation.
Is it a bedroom? Is the condensation only on window , which is usual?
You seem to be trying to fix a non existent problem.
The problem is the bedroom window area is noticeably colder and I can feel a draught when the wind hits that side. I think the big temp difference is causing the extra condensation as the other window on the other side of the room doesn't have any. So I'm trying to find the area to seal up. Sounds from above comments I need to look outside first perhaps.
Had some time to look at it more, it was a really windy and wet day. Lifted the window board again and discovered water ingress - see photo. Looks like the wind is blowing in rain so I've now sealed the fibreglass to the window frame with silicone. Need to find out where outside the "gap" is now.
