New soil pipe for upstairs bathroom

[Berserker]

Hi I have tried to find a similar question but have struggled so hopefully someone can advise. We want to put a bathroom upstairs, currently the toilet downstairs goes straight into the ground and out to a shared soil pipe leading to a manhole. We are closest to the manhole so the pipe is quite deep, 3m ish. The new soil pipe needs a stack and can't use the existing entry point, we have been quoted 5k to go 3m add a chamber and connect to the existing shared run. Is this sensible, also would it be easier to run 8m direct to the existing brick manhole and if so can it be done at halfway up at 1.5m?

Cheers for reading

 

[Ian H]

If the manhole is deep enough you could put an internal dropshaft in it. The water board may not like it because technically it’s their manhole. It gets done though and done right there are no problems.

There might already be a back dropshaft into the manhole from your house, if there is you would see a 4” round pipe poking through the manhole wall above the bottom inlet.

Are there any other drains nearby that you could connect into?

 

[CBW]

Are you not able to tee into shared soil pipe?

 

[Hugh Jaleak]

You cannot enter a manhole with a connection anywhere other than the bottom, foul waste needs to discharge into the channel of the manhole correctly, and avoid any build up on the benching which could then cause a blockage.

As Ian has said above, best option is to run to the manhole at a suitable depth, then fit a dropshaft or 'backdrop', to lower the connection to the right height. If not room internally, I dont see any reason why could couldn't put an external backdrop in, outside the chamber. Permission will need to be obtained from the Water Company though as it's their chamber. They will also indicate what they're happy to see done.

If you're doing this yourself, please observe necessary safety protocol with working in deep excavations, sewer gases and hygiene.

 

[just pumps]

You have Change of room permission yes?

 

[Berserker]

Hi, there is the shared soil pipe to tee into but it's 3m down and the material it's made of was only used for a couple of years in the early 70's and prone to colapsing aparantly so I don't think it's a good idea to play with it too much. Don't want half the road angry at me for backed up drains when I've just moved in.
Thanks for the advice, I'm not looking to do it myself, I think my contractor got a bit blinkered on option one which we thought it would avoid needing an application to the water company, which it would need now we know the pipe is also shared.

Thanks all

John

 

[Hugh Jaleak]

Hi, there is the shared soil pipe to tee into but it's 3m down and the material it's made of was only used for a couple of years in the early 70's and prone to collapsing apparently so I don't think it's a good idea to play with it too much.

Pitch Fibre possibly, awful stuff. Leave well alone. Hear of a lot of contractors now that are using a 'rerounding tool' to push/pull the pipe back into the correct shape, then putting a structural liner through to refurbish the pipework. Expensive, but cheaper than digging up to replace.

 

[cdbe]

Can't you convert the existing WC drain into an internal stack and run the new bathroom into it? Things like first floor joists running in the right direction help or even running under joists and boxing in - sounds like it will look horrendous but my sister's recently had her bathroom moved from front to back and the soil pipe runs along her hallway ceiling, now it's boxed in and decorated you barely notice it. Even a poo pump would work to save £5K.