Corrrect way to connect bathroom wastes?

Hi all.

I’ve been reading quite a few threads on here and it’s given me loads more to consider for what I thought was a straight forward job. But your thoughts would be most welcome.

I’m putting a new wash basin with pedestal in my upstairs bathroom (having removed the old one). I think I’m clear with everything from most of the many posts on this so far bar a couple of minor details with the wastes.

There is/was a shower, bath and basin all with separate waste pipes going through wall to outside where the shower then joins the bath waste, these two wastes then head over to the toilet stack.

However between where the shower comes through wall and toilet stack is the down pipe for the guttering, so currently the shower waste come right away from the wall and IMO its all joined quite badly so nothing quite holds together (its all loose and sags creating a lower bit trapping the shower water). I will try add a photo later.

To tidy everything up I was going to put a hopper into the guttering and drop all the wastes into that so nothing has to get to the toilet stack. Is this alright, or do I still need to have these wastes going into the toilet stack?

Also, if I’m looking at joining the basin and bath wastes under the floorboards am I right to be using a solvent joint with a HepO (?) pedestal trap fitted on basin?

Maybe I’m being too picky, but I want to get it right as most of it is under the floorboards and I don’t want to have to lift them again.

Many thanks in advance for any comments this might get.

I believe its better if your wastes are connected to the soil stack rather than guttering. Usually guttering ends up in the same place as soil stack anyway but if you are rural then your guttering might go to a soakaway.

Solvent weld joints are much better for inaccessible pipes and to be honest more easy to use than compression and pushfit. Only disadvantage is once its glued its glued for good.

connecting them together is OK and will be found everywhere but seperate connections are better, with both connected depending on position etc you sometimes get water backing up into bath when you pull the plug out of a full basin or sometimes gurgling if the waste isn't perfectly clear but it isn't a major problem

Not sure exactly what you mean with the stack/gutter Woneball; can we have that photo please

Thanks for your replies so far, heres those pictures I promised (I'm a newbie on here so having to learn to do this on the fly - should work ok)
I think you click on them to see them larger at hosts websites.

The black pipe on right is shower.
The lower black pipe on left is bath.
The middle gray/green pipe is basin.
The top gray elbow is to nothing - so thats coming out.

It looks like the soil stack and wastes are going to end up in same place (sewer). So im probably going to put the hopper into the guttering, appreciate advice to have them into soil stack but as you see the guttering gets in the way of the shower one at least. Unless you have any other ideas of how to get round it?
I would rather not have to move the down pipe for the guttering but there is some evidence of clips/screws suggesting it was over by the waste stack at some point.









Again, cheers for giving your opinion!

Several things here; presumably your toilet will still discharge into the soil stack & your not thinking of trying to put that lot through the hopper! Where does the rainwater discharge, into the main sewer or into a soak away? If it’s a soak away, I wouldn’t load it up with waste water from the bath/basin; if rainwater is discharged into the main sewer then as far as I know there is nothing to stop you diverting into the rainwater down pipe but it might pay to check with your LABC.

It’s far better to have separate runs to the stack/down pipe to avoid siphoning the basin trap. If you’ve no choice, you must fit either an anti-siphon trap or air admittance valve in the basin run to comply with building regs. Regs. also stipulate maximum lengths for pipe runs & branches as follows - 1.7m for 32mm; 3m for 40mm; 4m for 50mm; 15m for 75 & 100mm.

Thanks for the speedy response.

The toilet will still discharge into soil stack, wasnt going to touch that.
I believe rainwater goes into main sewer but I will have a scratch around in garden (under those stones - that cover everything) to see if there are manholes etc that might clear up where the sewer is and what it does.
Forgive me for being dense but what does LABC stand for?

I can use separate waste pipes (as they are now basically) but drop them into the gutter hopper instead of the stack (that was my main question - but i get the impression its ok). I was just looking into having fewer pipes on the outside.

Thanks for the max lengths, i dont think ill have a problem with that but its definitely good to know.

Woneball said:

Forgive me for being dense but what does LABC stand for?

Click to expand...

Failing to understand jargon is not being dense at all, it’s really a failing on those that use it. It is, however, something we can all slip into occasionally to save time. LABC = Local Authority Building Control. Good luck with your work