Hello all, I would appreciate comments on the likely quality of some leadwork around a couple of chimneys on external walls. There has long been some damp getting in at eave level and soaking into plasterboard ceiling so I had the old felt replaced with membrane and the lead replaced around the chimneys. However, this has not solved the problem and has in fact made it worse as, in heavy rain, water now clearly runs down a line of bricks visible at the back of the chimneys in the loft. The company have been 'reasonable' so far and have come out a few times and made some up-turns at the edges of the back apron but it has not solved the leak. Having looked at some Youtube videos of super work by professionals I am not convinced the work at my chimneys is as it should be. So, some second opinions would be very welcome - pics attached;
Opinions on this leadwork please
- Thread starter HDFogy
- Start date
OP,
I cant tell which chimney stack is which.
The leadwork is poor. It looks as though the leadworker had never done a stack flashing before doing your stacks. Every angle has been bossed no lead burning is showing.
Possibly they were working from a dimly understood youtube video.
Given you say its still leaking then all the flashings should be lifted and fitted properly with maybe some new pieces of lead.
Water running down the back of the loft chimney breasts usually means a faulty back gutter.
Back gutters should be flat and level, six inches wide and well supported by timber boards below the lead.
I cant tell which chimney stack is which.
The leadwork is poor. It looks as though the leadworker had never done a stack flashing before doing your stacks. Every angle has been bossed no lead burning is showing.
Possibly they were working from a dimly understood youtube video.
Given you say its still leaking then all the flashings should be lifted and fitted properly with maybe some new pieces of lead.
Water running down the back of the loft chimney breasts usually means a faulty back gutter.
Back gutters should be flat and level, six inches wide and well supported by timber boards below the lead.
ree, thank you for your comments. The company are no longer 'reasonable', having blocked my texts and emails so it seems I may have to strip that lead off and replace with a properly welded back gutter, properly cut step flashings and nicely oiled lead.
Thanks The Makie, I think the guy who did it was probably a decent 'roofer' as he made a good job of replacing old felt around the chimneys but having since read up about back gutters I am surprised he didn't opt to have one made-to-measure. But that's two who feel the work is not of a good standard which is what I thought. In particular the turn-ins are nowhere near 25mm which seems to be a minimum recommended, and are not even at a right angle in many places, and I can't think why he 'painted' it with the grey stuff. A shame really as it was a waste of some good scaffolding which might be needed again now to make good.
I'd start with a made to measure back gutter, Just lead is an online supplier.
Thank you, I have looked at Just Lead, and Leadworx, and both make me wonder why the guy bothered trying to bash a sheet of lead up on a roof. I've researched it and understand what is needed for a decent job with the lead but I'm not sure how the membrane should be laid at the back gutter. At the moment the membrane coming down the roof goes under the lead apron and I don't know if he has run the membrane all the way to the chimney bricks and left a decent upturn. As a reason for the leak he suggested water was overflowing off the sides of the lead apron and then somehow running back to the rear of the chimney (indicating he hasn't put a full length of membrane there) - so he turned up the apron sides, but then bashed it down so the tiles lay as they should! This has made the leak far worse at one of the chimneys.
Several information sources show the membrane lapping over the rear of the apron and Tyvek suggest adding an additional layer of membrane under the lead which I can see would help - but at the sides of the apron that would then have to go over onto the top of the 'main' membrane sheet. I could really do with seeing a clear diagram or better still a video of how this should be done - none of the excellent videos on Youtube show this aspect of the job. I would like to understand this so I can check any quotes I get now or even consider doing it myself - so any advice or reference to something online from knowledgeable people out there is very welcome.
Several information sources show the membrane lapping over the rear of the apron and Tyvek suggest adding an additional layer of membrane under the lead which I can see would help - but at the sides of the apron that would then have to go over onto the top of the 'main' membrane sheet. I could really do with seeing a clear diagram or better still a video of how this should be done - none of the excellent videos on Youtube show this aspect of the job. I would like to understand this so I can check any quotes I get now or even consider doing it myself - so any advice or reference to something online from knowledgeable people out there is very welcome.
The Mackie,
Thanks, on the face of it I agree with you but lead burning/welding would have indicated that it was the work of a lead worker.
There's also the bossing aspect - as you'll know, correct bossing means forcing lead from place to place to reinforce (thicken up) corners or shape the lead sheet without significantly reducing thickness.
Very few in my experience even know thats how its done or couldn't care less because its easier to blast the lead around corners etc.
FWIW: As you also probably know, City&Guilds used to present you with a square piece of code 4 sheet lead, & give you 2hrs to boss it into a hopper head.
Even the national treasure Pete Scholey on a Just Lead utub give a bad example of bossing.
Thanks, on the face of it I agree with you but lead burning/welding would have indicated that it was the work of a lead worker.
There's also the bossing aspect - as you'll know, correct bossing means forcing lead from place to place to reinforce (thicken up) corners or shape the lead sheet without significantly reducing thickness.
Very few in my experience even know thats how its done or couldn't care less because its easier to blast the lead around corners etc.
FWIW: As you also probably know, City&Guilds used to present you with a square piece of code 4 sheet lead, & give you 2hrs to boss it into a hopper head.
Even the national treasure Pete Scholey on a Just Lead utub give a bad example of bossing.
Don't hold your breath.
Yes I had two chimneys done although only one had serious damp problem - that one is now dry (at the moment, fingers crossed it stays dry) but the other now has far more water coming in than ever before - the pic attached shows the back gutter - far too small I think? And they have mortared the surrounding tiles to prevent any water backing up under them - again should that be necessary? However, I have just been up and sprayed the roof really well and although that gutter filled, no water came in. But then when I directed water at the bottom couple of feet of the chimney back it leaked as it does in rain. So next I think I will cover the top edge of the lead gutter with some 'flashband' and spray again. If that still lets water in then.... ? The roofer suggested the chimney brickwork was getting saturated and that was how water got into the loft. Is that possible, having taken only about 3 minutes of a water spray to reproduce the leak? I can't see it, but comments really welcome. Thanks all who are joining in! I'll write again tomorrow after another spray ....