Is this acceptable. Foul drain. Swift replies needed

[2021bela]

Hello, my question is will this be acceptable.

Here I have 2 rooms beside each other but need a toilet in both on the ground floor before 150mm insulation and 75mm screed get installed. One room is a bathroom, the other an ensuite. The toilet in the left will have a 90 bend under it and will be going into a 110mm pipe with a fall of 1/40 or slightly less. It will have a tee on it just before it leaves the exterior wall and will connected to another toilet above. Both pipes will be 150mm of the wall from the furthest part of the pipe. Once the pipe leaves the house it will have 2 x 90s which will be connected to an inspection chamber which will be connected to a septic tank with a 1/40 fall in the pipe.

In the toilet on the left it will have an air admittance valve to stop any back suction from the other toilet.

The bathroom with the exterior wall will be 2.4m wide. Enough to get the 1/40 fall needed for the waste water to get away without any issues.

Originally there was only supposed to be one toilet but now another needs added in the small box room on the left.

I could have an option of a saniflow toilet in left room but what I describe above would be my preferred option.


Another question I have about the rain water drainage. I have a run of 22m and the underground pipe will be 10inch black corri pipe. What would be the minimum fall I can get away with if the underground with this pipe. Can I go shallower that 1/110.

First fix going in in the next few days and all swift replies will be much appreciated. TY.

 

[2021bela]

 

[oz-plumber]

You can't run a toilet into a 'T' fitting.
You need a 45 degree junction and a 45 degree bend to make it 90 degrees

 

[exedon2]

Better still bring both out separately into a new chamber the two 90 bends not a great idea either.
If the top one is above is above finish ground level use a soil pipe junction with access plug in top to give rodding access.

 

[2021bela]

You can't run a toilet into a 'T' fitting.
You need a 45 degree junction and a 45 degree bend to make it 90 degrees

What about a sweeping tee?

I can't visulise what you mean by a 45 junction and a 45 bend to make a 90?

 

[ShaunCorbs]

Looks fine to me but I would vent it either durgo or external

30mm fall pm

 

[2021bela]

There will be a vent pipe coming of the inspection chamber.

My main worries are having issues with the tee. Would it flush away ok or can it block seeing it's a tee.

 

[exedon2]

You should probably read building regs document H section 2
2.49 deal with access points

 

[2021bela]

You should probably read building regs document H section 2
2.49 deal with access points

I will do this now. Thank you

 

[2021bela]

Would a saniflow not just save all the hasle with this. A saniflow toilet in that room, 1&12 pipe to outside with the connection to put in the small section of 110mm pipe I have between the 2 bends (1 leaving the house, the other going to the inspection chamber)