Newbuild plumbing fit

[Andy_S]

Hello

This is my first post so please bear with me.

I'm having a new build and got the point of plumbing for bathrooms. My issue is availability of plumbers(current plumbing cant do it now'arrgh) who can carry the work out in reasonable time frame for me. I've tried several' Im looking at months delay!

I need to connect two bathrooms to one outside foul pipe on one end of the building . One bathroom is on the outside wall the other more central to the building. My plan is to run a horizontal 110 mm foul pipe with a fall of 1:100 drop between the posi-joists and plumb in the toilets with fitment like below.

I've done a sketch to show layout

My question/s is can I attach the bath and sink outlets from the central bathroom to the right hand section of pipe?

Is this permitted with building regs. I cant seem to find anything saying I cant do it. I thought I'd ask for best method/practice

This will be the end of the run on the central bathroom. I was going to cap off the end solvent weld cap. With the fall being shallow I thought this would aid flushing of the foul pipe when bath empties or bathroom sink is run

 

[oz-plumber]

You are going to end up with major problems at 1:100 fall from a pan..

Bring the sink and and bath into the end of the drain, it may gain yo the extra fall you need

 

[Ben-gee]

I’m with oz, I never go below 1:80 , prefer 1:60.

 

[Andy_S]

Thanks for the replies. With a little bit of dry fitting I can attain 1:66.

Another question if you don't mind

My bath and sink waste is going into the rear of Y 110mm pipe, (right hand side) .

Is that normal practice to or do I use (space permitting) a clamp on boss fitting after the toilet, IE to the left of the Y piece?

 

[Ben-gee]

Go into the end if it’s more sense space wise.

Use an eccentric solvent weld reducer 110-50 and turn it so that the wastes enter the 110 “at the top” - not sure if it’s regs but it definitely works and I’ve done it several times when necessary.

 

[Andy_S]

Thanks for this. I think I've got my head around the practicalities around the waste now. May be back for more questions.

Onto hot cold feeds