Ready to hire?

Post your job in minutes, browse real reviews and choose who to speak to.Post a job

Need some tips or advice?

Plumbing

Upstairs toilet - downstairs bathroom. Can I use soil pipe smaller than 110mm?

Anonymous user 28/02/2024 - 2.53 PM

We are renovating our house and want to install a toilet (and basin) upstairs. The bathroom is currently downstairs with a 110mm cast iron soil connection through the external wall in the corner. I have a route planned for the soil pipe once it is downstairs, but... I need to build a false wall to accommodate rising and falling services behind the new shower, including the outfall from the new install, so I am wondering if I can use smaller soil pipe to minimise the depth of this false wall? I would rather not use a macerator on the new upstairs toilet if I can help it and am getting confused with Part H of the building regs as it often refers to 1 WC using a connection less than 80mm diameter... Can anyone make sense of my ramblings and advise if it's possible? Thanks in advance Adrian

Are you a tradesperson and able to answer this question?

2 Answers

kevin cassidy building contractors

Rating: 5 out of 5

Accrington

The 80mm diameter refered to is a smaller soil pipe and you could use this but most fitters would rather stick with the 110mm

Answered29 July 2012

Abby Contract Limited

Rating: 5 out of 5

Erskine

Adrian, Speaking from my experiences with the Scottish building control there is no alternative to soil piping other than a macerator which cen be reduced to a pipe often as small as 15 mm in diameter.There is a good chance the cast you refer to is 3 1/2 " pipe but any soli pipe you introduce must be 4". We often convert rooms to WC's or shower rooms and more often than not get 4" there but where this is no possible we install a Saniflo do not be swayed by cost if toy choose to go down this route pay the extra for a Saniflo and insure it is the correct model for your layout. Hope this helps. Alan @ abby contracts.

Answered29 July 2012