Quick bathroom waste question...

[caduceus]

Am I right in thinking that where you have a shower tray waste, the origin (shower tray floor hole) has to be higher that where the waste pipe meets the soil pipe?
Meaning wherever the route goes, as long as it either declines or levels toward the soil stack, it's ok. OR, can you have a slight incline somewhere so as to meet the existing waste coming out of the stack, in order to lower the height of the shower tray? As it would currently be around 25cm off the floor to meet the 'decline or level' route back to the stack.

Hope that makes sense...

Thanks for any help in advance
Cad

[Djtemeka]

You need a fall in level. If you don’t do this then the tray won’t empty. It will probably overflow if it’s a low level shower base as well. Build a platform for it with a step if you have to. Just make sure that the enclosure will fit.... ask me how I know

[thebraketester]

25cm? That’s gonna look ridiculous. Or do you mean 25mm?

If it’s 25mm can you not use a shower tray plinth and suitable feet to raise it up. Plinths are usually around 50mm.

[samdale]

Cut another hole in the stack below the height of the tray? Definitely needs a fall.

[stanwan]

The waste will always need a fall. It’s great if your soil pipe and joists fall the right way, but Sod’s law usually applies.

You can drill out joist centres but you must be careful where u do it.

Luckily, in my case the joists were already drilled out.

Alternatively, you can be creative and drop the waste run into the room below and then conceal it with a false wall or boxing. I had to do this in our first bathroom to avoid drilling through the joists.

[caduceus]

Djtemeka said:

Build a platform for it with a step if you have to. Just make sure that the enclosure will fit.... ask me how I know

I assume you mean height wise... Yes, that did cross my mind. not checked that yet but going after work to the flat.

[caduceus]

Thanks for the replies all.
Yes, 25CM is going to look a bit odd. Maybe a tiled step will be feasible, but not entirely sure about the space. It's a tiny bathroom (not mine btw).
It's a ground floor flat, so no going 'downstairs'.

I am very reluctant to start drilling into the soil pipe to be honest. Beggining to wish I hadn't taken on this job...

[jas xjr]

samdale said:

Cut another hole in the stack below the height of the tray? Definitely needs a fall.

That makes sense to me, easy to do too.

[caduceus]

jas xjr said:

samdale said:

Cut another hole in the stack below the height of the tray? Definitely needs a fall.

That makes sense to me, easy to do too.

Not in this property. There is no room below the toilet waste, as there is a join, to the orange coloured waste stack that goes into the ground.

[jas xjr]

I will get flamed for this...

Many years ago I plumbed a sink waste into the side of a toilet waste.drilled the right sized hole,put a rubber hung in and connected the waste from the sink.(that is the plastic pipe that comes out of the toilet. I simply did what seemed logical at the time.it worked fine.
I did it correctly after 20 odd years later.