Lead burning

[Julian]

Got a leak in one of the valleys on our roof.  Been botching it for a few years with Flexacryl or similar but it never lasts, so I decided to bite the bullet and have a go at a "proper" repair.

I tried soldering (plumbing solder) a patch on to some scrap lead with some success, but felt that proper welding was the way to go.

I don't have oxy-acetylene so I bought one of these mini blow lamps ... the ones that poncy chiefs use to brown crème brûlées.  What a great little tool ... I had my doubts that it would do it given that it's quite a dirty flame, and not such a tiny spot as a small, properly adjusted oxy-acetylene torch, but it did pretty well given that it was being driven by me.

I know the welds aren't pretty but they are strong and should be watertight.  It'll save a whole tranche of money if I don't have to replace the lead and it's really enjoyable to do.





 

[Jamesrl]

For someone who's never done Lead Burning before thats bloody good, whether the little torch will provide enough heat on the gutter is another thing.

As you say it's usually done with oxy/acetylene and a very small nozzle and a lot of practice.

[Head Womble]

Julian, please check inside the roof before you start heating it, valleys are normally supported by wooden boards.

If yours are not then this may have had a part to play in the leak.

[Tony]

Can't you just 3D print a succession of interconnected parts out of ABS?

[Julian]

For someone who's never done Lead Burning before thats bloody good, whether the little torch will provide enough heat on the gutter is another thing.

As you say it's usually done with oxy/acetylene and a very small nozzle and a lot of practice.

The heat sink effect will be greater on the roof, it's a long valley and hence very wide at one end, but I did some other runs on a bigger bit of lead and it didn't seem to make any difference.  The torch is quoted at 1300 C max and I was using it on it's lowest setting, so I hope it will be OK ... I'll find out later in the summer!

[Julian]

Julian, please check inside the roof before you start heating it, valleys are normally supported by wooden boards.

If yours are not then this may have had a part to play in the leak.

I know exactly what's below the lead ... It's a scaffold board I nicked off the scaffolding I had when I built the extension ... much cheaper than going and buying timber!

I also know exactly why the lead has puckered up and split with expansion .... it's because some bright spark thought it would be a good idea to sit the lead on a sheet of foamed PVC he had kicking about.  Over time I think it's effectively stuck the lead down preventing it from moving ... what a prat!

[Tony]

Yes, you want to find that guy and have a word with himse.. err, him.

[Jamesrl]

Yes, you want to find that guy and have a word with himse.. err, him.

Yep, there's always one dickhead know it all on site.

[Julian]

Yes, you want to find that guy and have a word with himse.. err, him.

When I catch up with him I'll make sure he puts it all right at his cost.

[Head Womble]

Stop beating around the bush, Julian you're a prat.

Now you're going to have to strip the valley tiles off, pull up the PVC backed lead and do a proper job, you can't go lead burning with PVC and wood underneath.
Loft areas are notoriously dry and go up quite quickly, but then again, yours may not be as dry as most.

[Julian]

Stop beating around the bush, Julian you're a prat.

Now you're going to have to strip the valley tiles off, pull up the PVC backed lead and do a proper job, you can't go lead burning with PVC and wood underneath.
Loft areas are notoriously dry and go up quite quickly, but then again, yours may not be as dry as most.

Yes, it'll be nice and wet under the lead, but I will take care ... probably have the hose up there with me!

On the test pieces I've done, the wood beneath only chars a little, no where near catching fire (I hope).

[Jamesrl]

Stop beating around the bush, Julian you're a prat.

Now you're going to have to strip the valley tiles off, pull up the PVC backed lead and do a proper job, you can't go lead burning with PVC and wood underneath.
Loft areas are notoriously dry and go up quite quickly, but then again, yours may not be as dry as most.

Yes, it'll be nice and wet under the lead, but I will take care ... probably have the hose up there with me!

On the test pieces I've done, the wood beneath only chars a little, no where near catching fire (I hope).

Be VERY careful,  wood can smolder unseen for days before bursting into flames.

[Head Womble]

You don't need the hose on the roof. you need it in the loft.

[Julian]

See where you're coming from, but the valley is over the party wall and the rooms either side have scelings, so no real loft space.

I'll weld the lead while the tiles either side of the valley are stripped off.  The only access will be through the felt but I might roll that back anyway to see what damage the water has done.