A bit of soil advice plrease

[bullterrier]

Hi all, I have a question about the best way to connect my soil pipe to a new "concealed everything" close-coupled WC (that has already been bought and is on site).

The soil pipe enters the bathroom from the stack for about 1.3 m alongside the wall (clipped against the first joist that runs tight to the wall) within the floor void at 18mm/m fall. The joists are 165mm deep so it is where it is in terms of depth from finished floor level.

Right now it ends as plain 110mm soil pipe with a chamfer but this could easily be swapped for a socket or whatever as the floor is up (chipboard and sensibly cut into panels for access). The WC will be at 90 degrees to this pipe, back to the wall with china concealing both the soil outlet and water inlet so my question is regarding the correct fitting(s) to use to:

turn the soil up through the floor and then...
connect the soil to the to the WC spigot while allowing it to then slide back against the wall while...
not falling off or leaking for the forseeable 😉

Plumbcentre suggest a McAlpine flexi (hoseclip at WC spigot then snake down AND sideways to pipe end). This would both reach and allow the WC to slide back but is this type of 90 degree down and then 90 degree sideways "contortion" OK?

Or do you have a better option? A standard bend would stick out of the floor quite a long way and leave little height between the top of the bend and the bottom of the WC spigot for a WC connector (but may be OK - it would be a case of add it then carefully measure. Then there is the slightly less tall option of a knuckle bend instead...

How would you do this?

Thanks in advance.....

 

[joni os]

Use 90 degree elbow on 110 pipe. Collar on pipe, spigot vertical up through floor. Fix timber nogging between joists and below elbow, to give support. Position spigot required distance off back wall. Use McAlpine or similar solid pan connector, 90 degree or swan neck. Fix to WC and lower unit onto greased spigot. Expect to precut leg of pan connector so rubber seal sits at correct height in spigot and beware of rubber detaching from spigot if you lift unit once in place. Avoid flexible pan connectors. The plastic is thin, becomes brittle after a period of use
and will eventually split in the circumferential folds.

 

[bullterrier]

Thanks that sounds better. Hopefully I can get the spigot the right distance from the wall to allow a solid pan connector to fully engage on the WC. I can feel some pipe clip shimming coming on.

 

[joni os]

Don't rely on pipe clips. You need solid support under elbow to prevent flexing when connection is made, and to ensure elbow doesn't drop whilst in use.