Can i please have some advice on my upstairs toilet plans... thanks

[simlock]

Not familiar with Geberit fittings, I'd stick to tried and tested orange fittings, are geberit compatible with other brands? Will you have to use geberit stuff from the inspection chamber all the way to both toilets?
Why do you need rubber couplings?
If it was me and there was no scope to replace the inspection chamber, I'd use an orange 'Y' piece to tap in as close to the inspection chamber as possible, then straight pipe (with a long radius 45 if needed) to a long radius 90 up to the new soil and vent that would have a swept 'T' where the soil from the new toilet would attach.
You'd also need air admittance for the downstairs toilet, either another roof line vent or an AAV, the important part for me though is to have separate runs for each toilet as much as possible. You don't want a blockage turning your downstairs loo into a bespoke chocolate and sweetcorn fountain 🤮
I base this on common sense, experience and regs - in that order
I don't do a lot of drains stuff, hopefully someone with more experience than me will be along to either agree or explain why that isn't the way to go.

Hi JCplumb, thanks for the reply, i was going to use the Geberit fitting, as it has no socket, and then when i cut the Clay pipe, and i can use rubber coupling to attach to each end to the middle of the pipe, if there are sockets on the ends, i'm sure you can't use rubber couplings, which seems the easiest way to fit it? and thus fit the Y into place, i have spoken to my local council, and the guy i spoke to said, that i can join the new to existing underground waste, and wouldn't need another waste vent adding to the new stuff, i asked if he knew what he was talking about, and he said yes, so obviously i'm going to do that, it save me time and money, i'm not totally sure where to add the Y and if i don't use a socketless Y how can i join this Y adequality? i'd appreciate any advice. i have just finished the outside pipe work today, need a few little things doing, and i'm ready to do the main connection.

 

[oz-plumber]

Aren't those Geberit fittings for fusion welding?

 

[simlock]

Aren't those Geberit fittings for fusion welding?

I really don't have a clue, i was thinking if it is suitable for underground use, then you can just put a rubber coupling adapter on the end.
[automerge]1587725334[/automerge]
Can anybody tell me if this can done using these fitting like? or try to use straight piece of pipe with bends, thanks

 

[JCplumb]

When coming from upstairs the soil needs a long radius bend there, those fittings in that configuration would be begging for blockages.
Example of a long radius bend.
You need your Y piece as close to the inspection chamber as possible(presuming there is no unused connection into the chamber you can use) and it should be almost horizontal (slight drop on straight and branch) then that needs to connect to the long radius 90 at the bottom of your new soil pipe using another length of soil, again with a slight drop(2.5 degrees iirc).
You may need to replace a section of the clay pipe with plastic and use a coupling that can 'slip' to allow you to have the wiggle room to push the pipe into the sockets.
Example of a transition coupling that can be used as a slip coupling on the smaller diameter PVCu pipe.
Just done a diagram of what I propose for clarity:
C = existing clay pipe
P = new plastic pipe
PB = plastic branch
LRB = long radius bend
IC = inspection chamber
TC = transition coupling

 

[simlock]

When coming from upstairs the soil needs a long radius bend there, those fittings in that configuration would be begging for blockages.
Example of a long radius bend.
You need your Y piece as close to the inspection chamber as possible(presuming there is no unused connection into the chamber you can use) and it should be almost horizontal (slight drop on straight and branch) then that needs to connect to the long radius 90 at the bottom of your new soil pipe using another length of soil, again with a slight drop(2.5 degrees iirc).
You may need to replace a section of the clay pipe with plastic and use a coupling that can 'slip' to allow you to have the wiggle room to push the pipe into the sockets.
Example of a transition coupling that can be used as a slip coupling on the smaller diameter PVCu pipe.
Just done a diagram of what I propose for clarity:
C = existing clay pipe
P = new plastic pipe
PB = plastic branch
LRB = long radius bend
IC = inspection chamber
TC = transition coupling
View attachment 43531

Hi JCplumb, thanks for the reply i really appreciate it, i have done another diagram, maybe that will help with my explanations, and maybe you can help me from that, i am short of room i think for what you saying to do, the IC, on your picture as reference, i am unable to put it in that place, as that would be in the garden, and the way i need to go is towards the wall, if any of it makes sense, and that would be what you're saying to do, have it as close to the branch connection as possible, another thing is well, i'm not sure if i can fit a long radius bend and pipe to the branch with the slope needed, and still be close to the IC at the same time, i can fit the Y branch close to the wall and the IC, but not sure what connection to use, that would work how you said, to get the right angle... hope you can advise me.

 

[JCplumb]

Sorry but I can't give you advice on how to bodge it, if you want to do it right then I have spent a decent amount of time thinking about your problem and offering what is (in my opinion) the solution.
You want to add a new w.c. upstairs, there are no short cuts that I know of that will work and pass regulations.
It's a pain in the rear, but to do it properly isn't simple and requires a decent amount of digging up to get right.
If you don't want to do it that way you could always look at getting a saniflow which can probably branch into your existing soil in the hole you've already dug out. You have to be careful what you put down the loo when you have a saniflow and there's some noise after the flush when it's doing its thing but the waste plumbing is a LOT simpler.
We have a resident saniflow guy who should be able to help if you go that route.

 

[simlock]

Sorry but I can't give you advice on how to bodge it, if you want to do it right then I have spent a decent amount of time thinking about your problem and offering what is (in my opinion) the solution.
You want to add a new w.c. upstairs, there are no short cuts that I know of that will work and pass regulations.
It's a pain in the rear, but to do it properly isn't simple and requires a decent amount of digging up to get right.
If you don't want to do it that way you could always look at getting a saniflow which can probably branch into your existing soil in the hole you've already dug out. You have to be careful what you put down the loo when you have a saniflow and there's some noise after the flush when it's doing its thing but the waste plumbing is a LOT simpler.
We have a resident saniflow guy who should be able to help if you go that route.

Thanks for the reply, i really appreciate you getting back to, especially on a saturday, my diagrams wasn't bodging anything, what i am asking, or trying to demonstrate, is what methods i am able to use to connect to the clay pipe, i have no previous experience of any of this, i don't even know what fitting i have to use, the diagram that i put on here for you to look at, was to maybe give me the best way to connect to the existing clay pipe, they don't sell socketless orange pipe, i can only find the black type of branch connector without sockets, i thought that may it simpler to connect the rubber coupling to, and the orange pipes only have minimum of two sockets on them, and not sure if there is suitable room for rubber couplings to fit on each end and not leak, and at the same time connect to the clay pipe, i am trying to do this properly, the last thing i want to do is have a leak and have dig it all back up again, as i said, i really appreciate your reply, have a great weekend, thanks
[automerge]1587830337[/automerge]

Sorry but I can't give you advice on how to bodge it, if you want to do it right then I have spent a decent amount of time thinking about your problem and offering what is (in my opinion) the solution.
You want to add a new w.c. upstairs, there are no short cuts that I know of that will work and pass regulations.
It's a pain in the rear, but to do it properly isn't simple and requires a decent amount of digging up to get right.
If you don't want to do it that way you could always look at getting a saniflow which can probably branch into your existing soil in the hole you've already dug out. You have to be careful what you put down the loo when you have a saniflow and there's some noise after the flush when it's doing its thing but the waste plumbing is a LOT simpler.
We have a resident saniflow guy who should be able to help if you go that route.

Thanks for the reply, i really appreciate you getting back to, especially on a saturday, my diagrams wasn't bodging anything, what i am asking, or trying to demonstrate, is what methods i am able to use to connect to the clay pipe, i have no previous experience of any of this, i don't even know what fitting i have to use, the diagram that i put on here for you to look at, was to maybe give me the best way to connect to the existing clay pipe, they don't sell socketless orange pipe, i can only find the black type of branch connector without sockets, i thought that may it simpler to connect the rubber coupling to, and the orange pipes only have minimum of two sockets on them, and not sure if there is suitable room for rubber couplings to fit on each end and not leak, and at the same time connect to the clay pipe, i am trying to do this properly, the last thing i want to do is have a leak and have dig it all back up again, as i said, i really appreciate your reply, have a great weekend, thanks


And saniflow is out of the question, my bathroom is 56 x76 i have no room for than but thanks for the suggestion.

 

[JCplumb]

As far as I know, no fittings are approved to branch into an underground soil pipe vertically the way you want here, you can branch horizontally then use 45's to alter the route to come up at a rest bend (LRB) into your vertical soil pipe, but you need to minimise flow direction changes and where possible use long radius fittings to minimise resistance to flow.
It doesn't take much deviation from the regs to create potential blockage hot spots and you don't want to have to dig up again in the future, so do it right once and never dig it up again.
The problem is the contents of the new branch, a shower waste or basin would probably be fine but what comes from a toilet has a habit of blocking pipes for fun if they're not done right.
I'm not familiar with that black Geberit fitting, it may be fine for underground connections and I can see why you'd want a socketless fitting but I don't know if it's suitable. Geberit make quality bathroom stuff so the fitting is probably a good one, I just don't know its applications. Orange plastic fittings I do know so I stick to them as a tried and tested solution. Fitted properly, the clipped rubber transition couplings work well and will outlive most of us (especially with this pandemic)
The ways you propose go against regs and building control are keen on underground work, not so much above ground but they won't pass your proposals. They might not even pass the solution I gave unless there's a really good reason why you can't run a new connection to the inspection chamber or replace it with one that will accommodate your new connection.

 

[simlock]

Hi JC, thanks for the reply, it's much appreciated, we have had a chat with a neighbour who has had there's done, who ever did there's, actually connected to the where the bath waste used to go out, in the gully, and the neighbour next door to them, went into the same pipe as i want to, but haven't spoke to them, as the first neighbour said both was done before they moved into the houses, so don't think they'll know how or what was used for the connection, i have just bought a long radius bend, and some rubber coupling, would you recommend using the same rout? through the Gully? thanks