Leak From Bathroom Sink / Bath Waste Coming Underneath Old External Wall Cast Iron Joint

[MrMiller]

Good Afternoon Folks

I have a tricky issue here which I am hoping someone may be able to offer some advice / recommendations with:-

We have a leak which has developed somewhere in the piping between our upstairs bathroom and the joint to the old cast iron elbow (? sorry, think that's the term) which connects on to what was the external downpipe on the side of the house. The problem is that we have an extension on that side, so all this pipework is now boxed in in the corner of our extension living room. I've landed up cutting the plasterboard off in the ceiling in that corner so I could see what was happening, which you should hopefully be able to see here:-

Couple of things to note there:-
1. You can see that the water is coming out and pouring down from directly below the cast iron joint as it sits on the wall. Hard to tell if failure where that corner join connects or the pipe further back towards the bathroom.
2. The space is very tight! The upper timber on the left could maybe be cut back an inch or so but that's really it space-wise.

In the bathroom itself, we have some really old pipework which seems to be one piece connecting the bath and sink waste and taking it to that old "external" wall seen in the video. It looks like this:-

What I'd ideally like to do initially is cut out that old piping heading out the bathroom wall there at the "exists here" point. Hopefully if I can somewhere around where I've got "sink waste" and at "bath waste" then I should be able to pull it out...

Once done, I'd ideally like to cut the "external" wall cast iron joint back to a decent point, e.g:-

And then hopefully get that cast iron corner piece out, get one length of 40mm pvc pipe straight through from the bathroom side to exit point here, connect a bend piece and then a bit extra piping to take me up to the cast iron "cut here" point and then connect using a suitable connector...

Anyway, does that seem feasible? I'd be interested in any views as to how difficult that join on the left hand side there is going to be to remove given the space constraint and whether my general plan there seems like a good way about it.

Also, given that this is only visible having cut away a section of the ceiling, I want to make sure I have the best components for the long term and won't have to be doing this again any time soon - therefore recommendations on the connectors to use, whether that's the best place to cut and make the join, etc would all be gratefully received.

Thanks.

 

[Madrab]

OK - chances are the lead waste pipe from the bath to the cast iron pipe in the wall has failed, either there is damage to the lead pipe or the or there is a blockage and the connection point and the caulking has given way and the bath waste water is now backing up and out at that point.

Yes, cutting the cast at the indicted point and running a new waste pipe from the bath would be the best bet, through the wall and then left and down into an adapter in the cut cast.

The trick will be - will the cast, once cut, pull free from the wall or will the wall surrounding it need chiselled out to free it up, so a bit of extra work may be needed. That and I would recommend that the complete bath waste run be replaced, right from the the baths waste within that bath all the way to the new connection @ the cast. That will then remove all the old iron and lead waste pipe as any join to that would be a future fail point and may difficult to connect to unless the pipe was nice and round and clean and a compression coupler would fit to it well. I presume it is an old cast bath with period fittings/furniture?

 

[MrMiller]

... The trick will be - will the cast, once cut, pull free from the wall or will the wall surrounding it need chiselled out to free it up, so a bit of extra work may be needed. That and I would recommend that the complete bath waste run be replaced, right from the the baths waste within that bath all the way to the new connection @ the cast. That will then remove all the old iron and lead waste pipe as any join to that would be a future fail point and may difficult to connect to unless the pipe was nice and round and clean and a compression coupler would fit to it well. I presume it is an old cast bath with period fittings/furniture?

Thanks Rob.

Yeah, the cast iron at the wall is the bit I'm most worried about, whether it's still going to be connected to the pipe from the bathroom and whether it will come away. Very limited access to the left hand side there were it comes out. My plan at the point I highlighted was to get a decent carbide blade to use with reciprocating saw. From what I'd seen that should give a clean-ish cut to connect to. As to getting it free at the wall side, I'm just hoping it comes away from the bathroom lead pipe easily enough. Otherwise it may be a bit of a think...

And yes, plan is to get rid of all the piping in the bathroom as well. It is an old, pretty long cast iron bath that I'd rather keep tbh but I think the other half wants replaced! Just thinking of the cut points and connecting in the short term.

Thanks again.

 

[Nige F]

I would attack from the inside - remove skirting and wall around the pipes and see what's going on - the lead has probably perished in the wall somewhere . Carbide blade later when you can see what's there

 

[Madrab]

The other point may be that the other end of that SS cast bend will be a cast socket and that could be imbedded and plastered into the wall and the lead will be connected blind into that knuckle behind the skirting in the bathroom. if so it's may need a fair bit to get it out of there.

After looking at it again I would be using a 1mm cutting blade on an angle grinder and then cutting to the left of that visible knuckle in the 2nd pic to start with. Then cut the lead waste inside the bathroom and then see if that section can be wiggled out, even with some persuasion. I'd be tempted to leave as much of that cast as possible, at least to start with, it can always be cut back right to beyond the socket if needed. If cut so close to the stack to start then you're committed.

As far as the bath waste pipe run is concerned then that's why I suggest replacing it all. It could be cut say half way to the skirting and then see if you can get a straight compression coupler onto it. It's the only time I would recommend not using a McAlpine fitting as they have an inner sleeve that doesn't work well with lead. A 40mm Floplast universal compression coupler could work (clean the lead up with some 120 grit) and may fit round that lead. That will also connect to a normal 40mm ABS pipe that can then run through the wall, turn left and then into the soil pipe.

 

[ree]

OP,
Madrab's idea to remove all the lead waste plus the trap (& the overflow) is a good idea that will work - but it would also require the present lead basin waste to be changed to 40mm, & to Tee branch it into the new 40mm bath waste at a better angle.

Two CI cuts: Cutting at the "cut here" mark, & cutting the CI hub bend tight to where it enters the wall.
On the bath room side: cutting the lead waste close enough to the wall to leave a graspable stub to pull out any remaining lead might allow a 40mmplastic waste to then pass through the CI remains in the wall?

Its difficult to say much without seeing some more pics with better lighting, & with the membrane pushed out of the pic.
Is the wall solid or cavity?
Is there a WC somewhere connected to the soil stack?
Is that a CI bend leaving the soil stack & entering a CI hub bend?

 

[MrMiller]

... and then cutting to the left of that visible knuckle in the 2nd pic to start with. Then cut the lead waste inside the bathroom and then see if that section can be wiggled out, even with some persuasion. I'd be tempted to leave as much of that cast as possible, at least to start with, it can always be cut back right to beyond the socket if needed. If cut so close to the stack to start then you're committed.

Thanks again for the further comments and advise re the bathroom side. Whatever I use there will be a pretty short term solution. In fact I might just bite the bullet and replace the sink / bath if cutting out the pipework anyway...

Re what you were saying there about left of the visible "knuckle", were you meaning both of them or just the first one (apologies, I'm no good on the naming conventions here!), so:-

Do you mean at point 1 there or point 2? I'd love to get in as far as point 1 but I think I'd really struggle to cut there and leave a big enough gap to get a connector over the replacement pvc piping bend piece there. And I'm guessing point 2 isn't great either given the connection size difference?

But you are right that the previous picture's "cut here" line doesn't leave much room to play with until the stack.

And my other worry about that is that the stack is actually bringing down the rainwater drainage as well - Sorry about the low quality but from this streetview grab its the pipe on the left hand side:-

So yeah, I don't want to get too close but the "cut here" point on from my previous post may be the best I can do...

 

[MrMiller]

OP,
Madrab's idea to remove all the lead waste plus the trap (& the overflow) is a good idea that will work - but it would also require the present lead basin waste to be changed to 40mm, & to Tee branch it into the new 40mm bath waste at a better angle.

Two CI cuts: Cutting at the "cut here" mark, & cutting the CI hub bend tight to where it enters the wall.
On the bath room side: cutting the lead waste close enough to the wall to leave a graspable stub to pull out any remaining lead might allow a 40mmplastic waste to then pass through the CI remains in the wall?

Its difficult to say much without seeing some more pics with better lighting, & with the membrane pushed out of the pic.
Is the wall solid or cavity?
Is there a WC somewhere connected to the soil stack?
Is that a CI bend leaving the soil stack & entering a CI hub bend?

Hi there - Thanks for the reply.

Sorry about the lighting - Had flash on but it's pretty dark up there. It's the old exterior of the house, so I think the wall is cavity - there will be brickwork on the outside and cinder block on the inside / bathroom side.

I just posted another pic in my reply above this one - The WC is connected to the pipe on the right hand side of the window in that pic, so not affected.

I'm not too sure on the terminology re the "hub bend" but basically the cast iron joins on the right hand side on to down pipe and the same section also joins to the pipe work coming down from the guttering on the left hand side of the window in the above picture.