Slightly moving waste pipe connection into soil pipe

[Mrflibble]

Parents have had a steel beam put into their hallway ceiling to adequately support landing and stairs.
This means that the waste from a sink and shower will need to be reinstated slightly lower into the soil pipe, as the pipes will now run under rather than through the beams (the joists will be cross battened for slightly lowered ceiling).
The current waste connection into the soil pipe is a massive old bodge so it needed redoing anyway, but the proximity to the old hole in that pipe is likely to be problematic... I’ll try to attach pictures.
Any thoughts and advice please?

 

[snowhead]

The solution is going to be to cut out that section of soil pipe from the connector above just under the floor, insert a short new piece and start from there.
There may be enough room to get a short boss section in to save cutting the hole and fitting a strapon boss.

 

[Mrflibble]

Thanks... assuming that the boss has a stop in it, IE not a slip coupling, I’m not sure how I’ll be able to get it in to the stack...
I don’t have any leeway for moving the pipe above upwards.

Just wondering if it would be feasible to cut a collar from another piece of soil pipe with one side slotted so that it can be sprung around the pipe, and solvent welded in place?

 

[Knappers]

I think there's enough room to cut stack at top of hole, remove and clean up remnants of existing boss and fit a proper 110mm boss fitting with additional slip socket if required to get it in.
My preference would be to cut in loft and run a full new length of 110.

 

[Mrflibble]

Unfortunately there’s a toilet connects into the stack just above that joint - it’s all boxed in so impossible to change or move the pipework above where I’ve pictured.
🙁

 

[plumbingdoctor]

Parents have had a steel beam put into their hallway ceiling to adequately support landing and stairs.
This means that the waste from a sink and shower will need to be reinstated slightly lower into the soil pipe, as the pipes will now run under rather than through the beams (the joists will be cross battened for slightly lowered ceiling).
The current waste connection into the soil pipe is a massive old bodge so it needed redoing anyway, but the proximity to the old hole in that pipe is likely to be problematic... I’ll try to attach pictures.
Any thoughts and advice please?

Hi
It would best to install thread tee connector reducer bushing

 

[Mrflibble]

Hi
It would best to install thread tee connector reducer bushing

Sorry, whereabouts do you mean?
That image may be misleading as there’s just a piece of pipe and an elbow stuffed with rag keeping the smells and water in the soil pipe, the original pipe from the sink and shower were all removed as they went through excessively large holes in the floor joists.

 

[Chuck]

Unfortunately there’s a toilet connects into the stack just above that joint - it’s all boxed in so impossible to change or move the pipework above where I’ve pictured.
🙁

You'll need to remove the boxing in order to gain access and then replace it again after. IMO, this sort of job needs to be properly without cutting corners and then proved with a pressure/smoke test before boxing it back in again. This is not 'impossible' for an amateur to do but it's more than most DIYer's would want to take on as a project.

I'm a bit worried that you are relying on 'an elbow stuffed with rag keeping the smells and water in the soil pipe'. Sewer gas is always a health hazard and can be very dangerous; you need to get the system properly sealed and airtight.

 

[plumbingdoctor]

Sorry, whereabouts do you mean?
That image may be misleading as there’s just a piece of pipe and an elbow stuffed with rag keeping the smells and water in the soil pipe, the original pipe from the sink and shower were all removed as they went through excessively large holes in the floor joists.

Hi
sorry to mislead I've not seen the original pipe from the shower and sink

 

[Mrflibble]

Hi
sorry to mislead I've not seen the original pipe from the shower and sink

It was badly installed pushfit, so I’m replacing from scratch.

Was planning on solvent weld for more peace of mind.

 

[Mrflibble]

Struggling to find a place selling a 63mm to 40mm solvent weld boss adaptor, other than the ones online.
All of the usual physical outlets seem to favour the rubber bung style adaptors... I’m not too keen on the idea, seems a bit daft if I’m going to solvent weld all of the pipe up to the soil stack boss, to then have it connected in via a rubber bung...
😐

 

[ShaunCorbs]

https://plumbingsuppliesdirect.co.uk/soil-vent-boss-adaptor-solvent-weld-abs/

 

[Mrflibble]

Yes, I found lots online but hoped to pick one up locally.

 

[ShaunCorbs]

Plumb centre City plumbing / your local plumbing merchant have them

 

[Mrflibble]

Progress so far. Removal of old pipe
I pulled most of that old calcified muck out of the branch above the floor.

 

[Mrflibble]

Lower part of branch before cleaning

Short socketed section onto bottom of branch

Stub added into floor socket for slip coupler to overlap

Boss pipe solvent welded
40mm adaptor for pipe from shower and basin

Slip coupling over butt joint. This was difficult, despite lots of lube!
🤣

 

[ShaunCorbs]

Looks good yep slip couplings arnt the easiest to move / set

 

[Chuck]

Progress so far. Removal of old pipe
I pulled most of that old calcified muck out of the branch above the floor.

You shouldn't be handling it without gloves. Risk of sepsis.

 

[Mrflibble]

I’ve had worse.

 

[WC1]

It's amazing what you find in old waste pipework.

 

[Mrflibble]

It's amazing what you find in old waste pipework.

Indeed, it’s no wonder the toilet was so slow when you consider that deposits filled about half the pipe.

 

[plumbingdoctor]

Lower part of branch before cleaningView attachment 61927
Short socketed section onto bottom of branch
View attachment 61928
Stub added into floor socket for slip coupler to overlap
View attachment 61929
Boss pipe solvent welded
40mm adaptor for pipe from shower and basin
View attachment 61930View attachment 61931
Slip coupling over butt joint. This was difficult, despite lots of lube!
🤣
View attachment 61932

Look good to go mate

 

[Mrflibble]

Looks good yep slip couplings arnt the easiest to move / set

I actually used a standard above-ground Floplast double socket coupler, and Dremel sanded off the two small stops inside. The main issue was that the collar that keeps the rubber seal in place kept popping off when I pushed it over the end of the pipe. Once in position however I was able to click it back into place.

By contrast, the Floplast below-ground double coupling is advertised as having “removable centre stop to use as slip coupling”.
Perhaps there is an equivalent above-ground type but I wasn’t able to locate one…

 

[WC1]

They exist but often it's easier to make one as you did.

 

[king of pipes]

You shouldn't be handling it without gloves. Risk of sepsis.

And hepatitis you don't want that it's really nasty I had a mate who got it off drains he went from 13 stone down to 9 and was ill for months , always use gloves and plenty of hot soapy water after completion of the work. Kop