Can I pipe basin waste into toilet flush pipe?

[RrogerD]

I have an outside loo with a small basin. Currently, the basin waste simply runs out through the wall and along the fence to pour on to the lawn. Not ideal.
I could of course add a proper soak-away but I was thinking, can I instead simply pipe the waste into the flush pipe of the toilet? I don't see why not?
If so, what connection should I be looking for?
Thanks

 

[blup]

I would think there is a regulation against it otherwise you are relying on the wc not to be blocked

 

[RrogerD]

I would think there is a regulation against it otherwise you are relying on the wc not to be blocked

Why would this be a realistic issue? Surely if the wc was blocked then there is a bigger problem at hand. Plus, the basin is literally adjacent to the toilet and so if wc is blocked then it is easily seen.
On reflection, would syphoning be an issue? There is of course quite a fair bit of water flushing down into the loo.

 

[blup]

As I understand it you are tapping into the flush pipe, so relying on the level of the water in the pan to rise sufficiently to spill over th trap. If you are adding direct to the soil pipe that is different

 

[Elsa TLC]

You can buy these. So I can't see a problem.
There obviously are ways. NRV maybe but best using a fanny trap.

Affine Tivoli 2-in-1 Toilet With Sink On Top - Close Coupled

Affine Tivoli 2-in-1 Toilet and Sink with Soft Close Seat - Close Coupled Toilet. Internet Only Price. In stock: Delivery Next Day. Rated 4.8/5.

www.plumbworld.co.uk

Or maybe just buy one of these. Far easier.

 

[Hugh Jaleak]

It's not common practice, my main concern would be when the WC is flushed, the pressure of the water could push back up the basin waste, but that could probably be overcome with a Non return Valve just before the waste connects into the Flush Pipe.

Need to measure the Flush pipe, I suspect it'll be around, 40mm diameter, in which case check a 40mm Compression Waste Tee will fit before butchering the flush pipe.

 

[trojanhawrs]

Wouldn't recommend a nrv on a low head gravity discharge. Better to tee in the soil pipe

 

[Dereekoo]

No issue whatsoever did it to my wc and wash basin 8 years ago with one of these

 

[trojanhawrs]

No issue whatsoever did it to my wc and wash basin 8 years ago with one of these

That's the soil pipe, he's on about using the flush pipe between cistern and pan

 

[Dereekoo]

That's the soil pipe, he's on about using the flush pipe between cistern and pan

Wow thats so far out the question never even registered, perhaps he can just loop the waste pipe over the seat and just be careful when he sits down

 

[fixitflav]

On reflection, would syphoning be an issue?

Good chance of syphon emptying the sink trap when flushing, but that wouldn't be a problem, as the outlet isn't in a smelly area, you could do away with the sink trap.
Though having said that, I think it's a bad idea anyway. The waste from the sink will sit in the toilet bowl till it's next flushed. That could give a smell problem, even used wash-up water starts to smell after a few hours.
Can't you go into the toilet waste pipe downstream of the trap, maybe drilling through the wall if no room inside?

 

[Elsa TLC]

 

[Fred Blogs]

Bloody stupid idea.

 

[Elsa TLC]

Bloody stupid idea.

Great idea. The first time I see these was in Australia.

You would flush the toilet - the tap would run so you could wash your hands, in-turn the soapy grey water would fill the cistern ready for the next flush.

 

[fixitflav]

Great idea. The first time I see these was in Australia.

You would flush the toilet - the tap would run so you could wash your hands, in-turn the soapy grey water would fill the cistern ready for the next flush.

It doesn't sound like he wants to replace the whole set-up, at considerable expense. And he wants to drain into the pipe between cistern and bowl, not into the cistern.