Flat roof above bay window not draining - can I add a slope?
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the_duckchild
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Flat roof above bay window not draining - can I add a slope?

by the_duckchild » Tue Nov 29, 2022 10:44 am

Hi - as you can see in the attached images we have a small flat roof above a bay window in our (Edwardian) house, which is not draining water.

The left hand side of the roof drains into the lower portion OK, but the water then pools up. The drain was previously blocked, and we had this cleared, to little effect on the pooled water. Following a heavy storm I think this has probably contributed to a small leak in the room below, and I would like to make sure this roof is draining correctly.

I think I need to add additional slope to the lower portion of the roof, and perhaps reseal around the edge with flashband, but I am not sure how best to go about rectifying the slope?

I'm hoping somebody may be able to help with a suggested solution
Attachments
view towards drainage hole
view towards drainage hole
The issue!
The issue!
This looks too high to drain effectively to me, but in any case the slope does not drive even quite large amounts of water towards it.
This looks too high to drain effectively to me, but in any case the slope does not drive even quite large amounts of water towards it.

stoneyboy
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Re: Flat roof above bay window not draining - can I add a slope?

by stoneyboy » Wed Nov 30, 2022 10:53 pm

Hi the_duckchild,
You may be better off forming a new drain hole at the lowest point, this feeding out to a new section of gutter around the bay.
Increasing the levels of the flat part may increase the chances of water ingress because the upstand will effectively be reduced.
Regards S

the_duckchild
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Joined: Tue Nov 29, 2022 10:02 am

Re: Flat roof above bay window not draining - can I add a slope?

by the_duckchild » Thu Dec 01, 2022 10:50 am

thank you - it's really hard to tell where that is currently as the water seems not to be moving very much at all. I think we may need to reseal around the edge of the roof in any case, so I am thinking this is moving towards being a job for a professional.

especially as it is on the third floor.

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