Lead Roof Hangers Causing Leaks

[rideforever]

We have a dormer roof with horizontal seam that has the hangers (folded over bits of lead) that hold the top section in place.
The roof look like it shouldn't leak nevertheless we have got water coming through the horizontal seam.
We masticed the seam together but still had some water coming through, at odd intervals like it was pooling then leaking.
Then we went back up and also masticed the small 1" hangers - then the roof was water tight.
Now I am thinking the hangers were causing the leak the whole time.
Anyone with similar experience ?
The hangers face the direction of flow of the water ?
Is it possible to weld on a hood over the hangers so they are out of the path of water ?

(Attached photo just indicates what I mean by hangers if it's not clear.)

 

[Nige F]

Lead clips Nicely done rolls there. The top and bottom sheet are just lapped ( though in the picture there may be an ant-capillary groove in the bottom sheet-hidden ) Does your roof have the rolls too.

 

[rideforever]

Lead clips Nicely done rolls there. The top and bottom sheet are just lapped ( though in the picture there may be an ant-capillary groove in the bottom sheet-hidden ) Does your roof have the rolls too.

Yes my roof is very similar to this one. Including the rolls.
As I said it leaked even after masticing the horizontal overlap, until the lead clips where sealed then it because water tight and bone dry. Also the leak seemed to be pooling / leaking sporadically. So my feeling is that the only explanation is that the clips being in the flow of water are drawing water underneath from time to time.
And that instead of replacing the roof, I could get hoods welded over the clips so they are out of the flow of water as a permanent solution.
Sound idea ?

 

[datarebal]

The one in the picture is half decent apart from the laps. If anything the clips should help prevent capillary. Any pictures of yours?

 

[rideforever]

It's not a great photo but here is one. Has a lot of mastic on it now though, this was before.

 

[datarebal]

the problem is likely the lap system. mastic isn't a permanent fix

 

[rideforever]

the problem is likely the lap system. mastic isn't a permanent fix

Yes indeed.
Firstly we masticed the lap from end to end, but the leak still came through strangely.
Then I noticed the clips had not been masticed- once I did that it was watertight and bone dry.
So ... now my feeling is that instead of throwing the roof away, we should just weld on some covers / hoods over the clips so that they are out of the flow of the water.
Sound idea ?

 

[datarebal]

you do not need to throw it away.burning hoods over the clips is easy enough but I honestly doubt it will be the problem/solver.
pitch, and lap joint is the problem. Any idea how much lap each bay has?

 

[rideforever]

Any idea how much lap each bay has?

Dimensions are Length = 192 cm, drop 43cm, I make that about 14 degrees
Lap is 8"
Width of clips/hangers is 2"

I wonder if it's possible to insert a 60cm strip of lead creating 2 new 12" laps, possibly welding it to one side.

Or insderting a step, by removing top sheet, screwing new board to top half, then replacing top sheet, and possibly welding on middle bit to form the step.

Otherwise throwing away a new roof and starting again is £1800.

 

[datarebal]

The angle looks less than 14.. I make it around 12.. looks less.
I would be inclined to insert a step.