Flat roof gulley advice

[mollykent86]

I am looking for advice on the repair of a gulley running along a flat roof.

I have a flat roof about 3m long, it is on an extension to the main house and has a gulley going from the wall of the main house, along the flat roof to the hopper. There is a drainpipe running along the gulley, which takes the water from the butterfly roof on the main house.

Water is running down the wall of the extension behind the hopper when it rains. I had a roofer come out and replace the hopper and the lead at the end of the gulley. The water is still coming out and running down the wall. I have opened up the ceiling underneath and I can see that there is water soaking through the insulation under the gulley (in the front half only).

The roofer has suggested that there is a leak further back in the lead and this is soaking through the wood in the bottom of the gulley and coming out. I am concerned that the roofer didn't do a good job of the repair in the first place. The patching of the lead looks messy. I don't think it has been welded and I am not sure they have sealed the roof felt back down properly

I have been told by three roofers:
1) I need all the lead in the gulley replaced
2) The gulley should be refelted
3) The entire flat roof should be replaced.

2 questions: 1) Does the original repair look okay and of the three options, which one is the best to go with? Replacing the lead and the entire flat roof are very expensive and I don't want to do this unless I absolutely need to

 

[^woody^]

The lead should project out and into the hopper. This ensures all discharge from that box gutter goes into the hopper and nowhere else. This may involve a soldered tray similar to the profile of the box gutter which extends out past the roof edge.

New felt should be fitted over the junction of the lead and existing felt to overlap the joint and seal it.