We had a loft extension build a year ago.

There is a "feature" left from the original roof that consists of a
small pitched roof with tiles at the old roof level.

The down pipe from the flat roof gutter has an S bend and an open shoe
resting on the small pitched roof. The water then runs down a tile or
two to the gutter below it.

When it is raining there is no problem. But once the rain has stopped
and the final run-off from the top roof is just a small trickle then we
get a constant drip-drip which is driving us mad - as it is just outside
the bedroom window.

What seems to be happening is that somehow, instead of running down the
inside of the down-pipe as one would expect from a S bend, there is a
drip coming straight down the middle of the pipe and hitting the bottom
of the shoe which is resting on the roof tile.

I have checked at roof level and all is well. In any event, the S bend
should ensure that the water runs down the inside pipe wall.

There must be some lip at the bottom of the S bend that is throwing the
water off the wall.

Any ideas what I can do, short of dismantling the pipe-work? (not very
simple being three floors up)
--
Les Desser
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