Flat Roof Bay Window Lead Flashing - Leaking

3 Sep 2008
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Tyne and Wear
United Kingdom
Last night in the terrible wind and rain we had i developed some leaks in my bay window. I#t has a flat roof and is flashed up into the wall beneath my bedroom window. The roof itself doesn't loo too bad and i wonder whether driven rain is the cause of the leaks inside...it seems to only leak with rain AND windy conditions (ie - we have had heavy rain in the past but on a relatively still day and no leaks). I attach photos...if it is driven rain getting in - i am imagining it is under the lead - is there a way to seal the lead to the flat roof?

thanks for any help that comes my way


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Don't try and seal the lead to the felt.
Your lead flashing is coming away from the wall. Almost certainly were
the water is getting in.
As above.

But there may be more to it than your pics show?
Why not post a couple of pics showing the whole flat roof and the stone abutment?
are those stone sills and mullions in the picture or maybe a stone banding course, as they don't look in great condition. Any chance of a wider shot
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Agree,It does look like the stone work needs some attention.
And the flashing needs refitting from what i can see.
it is a stone window cill. It is hard to get a full shot as it is quite high and i regretably don't have a long ladder!!!
now i look again at my photos, there does seem to be quite a gap between the stones - would this be filled with mortar? i am a novice at external work! i was going to get some mortar, scrape all the existing mortar that is currently holding the lead in place, then replace with new mortar - now i am thinking i will do the same between stone sections - does this sound like a good plan?
If you can work on the area in the pic by hanging out of the window, how come you cant take a pic?
Tied in with a line and guarded by an assistant, why not go on the flat roof through the window?
The lead flashing across the back of the bay and the pointing needs to be removed, and a pic taken showing whats happening behind the flashing?

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