Soil Pipe Fall - advice please

[Pickup]

Hi

I'm moving the WC in our bathroom which is on the ground floor. The soil pipe currently drops vertically about 850mm to the bottom of the crawl space under the floor where it is connected to a 90 deg bend taking the waste outside.

The new toilet outlet will be approx 2m away from the existing outlet. Am I better to run the new soil pipe from the WC to the existing 90 deg bend (ie at about 25 deg) or am I better to have a slight fall from the WC outlet until it is over the 90 deg bend and then drop vertically?

If its the latter what is the correct fall? I think I read somewhere else on the forum 1 in 40 is right?

Thanks

F

 

[doitall]

Best to run it at 40degs and drop vertically into the bend.

 

[Richard C]

Hi
I think I read somewhere else on the forum 1 in 40 is right?

That’s fine; 18mm per metre is the minimum for soil but a fall of 25 degrees is far too steep let along 40 degrees

It maybe me but I think there might be some confusion here; if the fall is too great over a run of any appreciable distance the ****e won’t flow away with the water, possibly leading to the obvious nasty results.

As it's on the ground floor, do you have a vented soil stack or an AAV fitted? If not you then it won’t comply with Building Regs.

 

[doitall]

Yes I did mean 1-40

 

[Richard C]

Yes I did mean 1-40

An unusual one for you m8

 

[Agile]

On this occasion I will agree that DIA will have known it was 1:40 and it was a brain to keyboard interface error!

Tony

 

[doitall]

Yes I did mean 1-40

An unusual one for you m8

Not thinking what the fingers are doing, I just read 25deg, and typed no, it should be 40 degs An head banging emoticon.

 

[Richard C]

Wish Agile was my wingman

 

[Pickup]

Guys,

many thanks, existing soil pipe is vented outside (2 pipe system?) so hopefully no problems.

Thanks again.

F