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Soil pipe run under suspended timber floor - bends (sense check)

Postby joeka101 » Sun Jan 16, 2022 1:09 pm

Hi all,

We're planning to add a toilet to a bathroom. This will be a tanked wetroom (area below floor will become inaccessible). Nearest soil pipe is in toilet room on other side of hall. Keen to avoid macerator. Suspended timber subfloor (40cm void / 29cm below joists).

New toilet will drain vertically then immediate 90degree bend to horizontal. Horizontal run of new soil pipe is 4.2m (enough space for 1:40 fall below the joists). However, it will need two long radius (roddable) 90degree bends. Toilet room floor is oak boards (screwed) so it could have a rodding point below the floor in toiler room (ie take up the boards if blockage).

Does this seem a reasonable approach? I can accept the very occasional inconvenience of taking up the boards to unblock.

As an aside, would the chance of blockage be reduced if the shower also drained in to this soil pipe (ie more flushing!)?



Long Radius 110mm Bend
Bathroom Plan.png
Bathroom Plan - proposed soil drainage in blue.
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Simply Build It

Postby stoneyboy » Mon Jan 17, 2022 10:10 pm

Hi joeka101,
Don’t see any problems but do support the soil pipe on pads under the floor. There should be no need for a roofing point - access is from the outside inspection chamber and a drain snake will easily deal with the layout shown.
Regards S
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