New utility/bathroom waste advice please

[8ball]

Hello people I'm just making a start on planning my plumbing for a new downstairs toilet/utility room which is going to be joined to the main vented soil stack of the house.

 

Is there anything extra I need regarding venting? its already vented upstairs.

 

Edited June 9, 2017 by 8ball

[Nickfromwales]

For the upper union don't have the waste boss opposite the soil as the first fitting under it. Drop lower and boss in further down to stop 'stuff' hitting the boss inlet and causing issues.

If the vent is outside to atmosphere then you don't need to do any more than is shown . 

[8ball]

10 hours ago, Nickfromwales said:

For the upper union don't have the waste boss opposite the soil as the first fitting under it. Drop lower and boss in further down to stop 'stuff' hitting the boss inlet and causing issues.

If the vent is outside to atmosphere then you don't need to do any more than is shown . 

Thanks Nick, can the waste from the sink, washing machine and water softener be bossed into the 100mm soil at the toilet location or is it better to run it back to the main soil stack? I'll save about a metre of 40mm pipe also its tight at the 100mm branch to connect.

 

Ta

[Nickfromwales]

All depends upon if it's boxed in and you can lift the waste pipes accordingly. You can't go into the end of the soil as you'd have to have the WC outlet going into a Y-branch first to direct the black water flow and only then can you fit to the end via a 110mm x 50mm reducer.

You will only be able to fit a tee behind a 'flush pipe' ( high level separated cistern ) WC which are a bit old and ugly as a closed coupled WC won't have room for a tee and a pan connector behind it, so basically you'll have to boss into the top of the soil pipe and then turn 90o right to send the waste over. You'll could struggle TBH because of the height ( fall ) needed for the washing machine upstand, unless you buy a combination trap for the sink and connect the washing machine waste to that. 

 

[Jeremy Harris]

I had a similar conundrum for out downstairs WC, which was just to the right of the stack.  Further right is the utility sink, then a run, with a U bend trap at the end, connected to a vertical drain that goes upstairs to the services room for the water softener, MVHR condensate drain etc.

 

What I did was fit a branch to the base of the stack, then a very short run to a Y connector right behind the WC, then another short run of 110mm ending in an upstanding elbow, with a cap on it and a 40mm reducer, right behind the wash basin that's to the right of the WC.  The waste pipe that runs across the back of the utility room, with the sink and washing machine connections, plus the run from the services area, just goes through the wall to the WC and connects to the short vertical drop where the wash basin waste is.  This keeps the "black water" well clear of the "grey water", because of the upturned elbow on the end of the short length of 110mm.

 

From your drawing, I think the same arrangement would work for you.

Edited June 10, 2017 by JSHarris

[8ball]

On 10/06/2017 at 16:14, Nickfromwales said:

All depends upon if it's boxed in and you can lift the waste pipes accordingly. You can't go into the end of the soil as you'd have to have the WC outlet going into a Y-branch first to direct the black water flow and only then can you fit to the end via a 110mm x 50mm reducer.

You will only be able to fit a tee behind a 'flush pipe' ( high level separated cistern ) WC which are a bit old and ugly as a closed coupled WC won't have room for a tee and a pan connector behind it, so basically you'll have to boss into the top of the soil pipe and then turn 90o right to send the waste over. You'll could struggle TBH because of the height ( fall ) needed for the washing machine upstand, unless you buy a combination trap for the sink and connect the washing machine waste to that. 

 

Again Nick thanks for the info, the combination trap was on my list as the Washing machine in very close to sink. Yup just purchased closed coupled toilets a couple of weeks ago so the tee behind is a no no.

 

On 10/06/2017 at 16:25, JSHarris said:

I had a similar conundrum for out downstairs WC, which was just to the right of the stack.  Further right is the utility sink, then a run, with a U bend trap at the end, connected to a vertical drain that goes upstairs to the services room for the water softener, MVHR condensate drain etc.

 

What I did was fit a branch to the base of the stack, then a very short run to a Y connector right behind the WC, then another short run of 110mm ending in an upstanding elbow, with a cap on it and a 40mm reducer, right behind the wash basin that's to the right of the WC.  The waste pipe that runs across the back of the utility room, with the sink and washing machine connections, plus the run from the services area, just goes through the wall to the WC and connects to the short vertical drop where the wash basin waste is.  This keeps the "black water" well clear of the "grey water", because of the upturned elbow on the end of the short length of 110mm.

 

From your drawing, I think the same arrangement would work for you.

Thanks for the tips JS, that reminds me I was going to ask about plumbing in the Harvey twin tank that I should be purchasing soon as I see you have the same model. I'll start a new thread for that one in a few days

 

Ta