Bends in soil pipe (horizontal plane)

[Ellsa100]

We are relocating our toilet.

The soil pipe connecting the toilet (in its new position) and the vertical soil pipe will need to have 3x 92.5 degree bends on the horizontal plane (the overall horizontal soil pipe length will be about 2.5m and would have a fall of 1cm for every 40cm).

Is this ok or are 3x bends like this too many and result in blockages?

Thanks

 

[jj4091]

I'm not a plumber so do not know if there are any regulations that prevent that, but as you suspect, common sense tells you that with no fall then the risk of blockages must increase. Also I would think clearing said blockage if it were to happen would be difficult with so many bends.

 

[Ellsa100]

Thanks - the horizontal plane would still have the necessary fall - do you still think having 3x bends is problematic?

 

[johnny2007]

It surely can be a potential problem.
Ho far are the bends from each other?
Isn't there any other way to lay the pipes and avoid 3 bends?
Show your pictures, maybe someone will find a better way.
Or, if you have space, use the formed bends for underground pipes which won't cause any problem but take up space.

 

[Ellsa100]

Here is a drawing of the proposed layout. Toilet will have concealed cistern. The main reason we are doing this is so we can fit a double vanity on the wall opposite the door.

Thanks!

 

[johnny2007]

It's ok imo.
The long 2400mm run helps.
Make sure you have a good fall, iirc between 18mm and 40mm per metre, not more, not less.

 

[Nige F]

and would have a fall of 1cm for every 40cm).


Thanks

can wc go on the outside wall ?

 

[Ellsa100]

can wc go on the outside wall ?

Not possible because of the space between the outside wall and door when opened. Also there’s a window on the outside wall which would interfere with where the concealed cistern goes.

 

[Notch7]

you could put a 90 deg access bend at position 2

2 out of the 3 bends and the long straight are external so at least if you have problems its not pipework hidden under tiled floors or tiled boxing in

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[Hugh Jaleak]

It's not ideal, personally would be looking at relocating or providing another stack on the back corner, so soil pipe can turn 90º from back or WC and go straight through the wall into the stack. With your proposal, are you taking the pipe externally, then returning in to the inside to connect onto an existing stack?

 

[Ellsa100]

It's not ideal, personally would be looking at relocating or providing another stack on the back corner, so soil pipe can turn 90º from back or WC and go straight through the wall into the stack. With your proposal, are you taking the pipe externally, then returning in to the inside to connect onto an existing stack?

Yes, with my proposal I'd be taking the pipe external, then returning it to the inside to connect to the existing stack.

 

[Notch7]

With your proposal, are you taking the pipe externally, then returning in to the inside to connect onto an existing stack?

That doesn’t seem great.

Inside to outside to inside…to outside

 

[jj4091]

How are you going to have any fall if you take it out at floor level and back in at floor level

 

[Ellsa100]

That doesn’t seem great.

Inside to outside to inside…to outside

It would be inside -> outside -> inside

 

[Ellsa100]

How are you going to have any fall if you take it out at floor level and back in at floor level

think there will be a small fall - think the requirement is 1cm fall for every 40cm of horizontal?