Waste pipes for single storey building

[hudster]

I've got an old outside loo. The waste currently goes directly down through the concrete floor, and then runs outside a couple of meters to join the main waste. There is no sink or other waste pipe in the room.

For various reasons I need to move the toilet within this building, and fit a sink with its own waste. Rather than dig up the whole slab, I'd like to remove the toilet and concrete over the waste hole, and fit new wastes through the wall for the loo and sink.

As it's a single storey building, I'm not sure how to run the wastes once they are outside. Should you have a soil stack in this situation as you would for a two storey building?

 

[Nige F]

you could have a stub stack and/or a gulley just for the basin/sink wastes- outside cut into the drain run ,Providing the drain is vented elsewhere ( which it should be from your description ) leaving the pipe into the toilet as is and concreting it over inside Is the old toilet still in place ? - I`m after a lead flush pipe for a high level WC cistern

 

[hudster]

Having re-read the regs I think a stub stack would be ok (the drain is vented further up as it connects to the main 2 storey open soil stack).

Would I need an air admittance value inside the single storey building, just above the sink as this part of the drain has no ventilation? It's going to be a utility room too so needs to accept waste from two sinks and a washing machine.

 

[hudster]

Is the old toilet still in place ? - I`m after a lead flush pipe for a high level WC cistern

Yes old toilet is still there. Not sure if the flush pipe is lead, will have a look next time I'm out there

 

[Nige F]

Having re-read the regs I think a stub stack would be ok (the drain is vented further up as it connects to the main 2 storey open soil stack).

Would I need an air admittance value inside the single storey building, just above the sink as this part of the drain has no ventilation? It's going to be a utility room too so needs to accept waste from two sinks and a washing machine.

no AAV required there , but you might want to put a small one on the end of the pipe run if it`s long and the traps might draw out . Re. flush pipe , contact email is in my profile , Thanks. :

 

[hudster]

I think I would add one, there's a nice diagram which seems to exactly match my situation right at the bottom of this doc: http://www.floplast.co.uk/uploads/Air Admittance Valves.pdf

 

[hudster]

Re. flush pipe , contact email is in my profile , Thanks. :

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