Hi folks. I have a pair of 110mm push fit soil pipes in a room that used to be a WC but is being converted into a utility. The 110m pipe connections I refer to are a 90 and a tee and are buried in the concrete slab. The connecting lip of each 110mm fitting sits flush with the top of the concrete slab.
To convert from 110mm to 40mm, there is temporarily a couple of polypropylene reducers like this:
Though in order to get the 40mm wastes in a better position I'll be converting to these (or similar):
Now the issue is that the concrete slab is horribly uneven and is in dire need of a few bags of self leveller. The one I usually use is Mapei Ultraplan Renovation Screed.
My concern is that this will flow over the top of the 110-40mm reducer and will seal around the little 40mm spigot.
Now being sensible, I can't actually see anything wrong with that. The reducer is a push fit, so the rubber ring will be hidden well away from the levelling compound so I shouldn't need to worry about chemical issues. Similarly, the levelling compound will lock the reducer in place so should logically help rather than hinder the seal. Plus it'll look very neat.
I'm on a one-house septic system so don't need to worry about the sewers backing up - and if I ever did need to access it, I could chip the leveller out of the way.
Does this seem OK to everyone else? I do still have a lingering unease about cocooning a plastic fitting.
The only alternatives I can see are either to extend the pipe up a few inches and reduce from there - but there'd still be a joint underground and if anything, there'd be a chance the stub could act as a lever on the joint when knocked. Or I could put a ring around the waste pipe to act as shuttering when I self level, but this would create a pair of odd sumps in the room.
To convert from 110mm to 40mm, there is temporarily a couple of polypropylene reducers like this:
Though in order to get the 40mm wastes in a better position I'll be converting to these (or similar):
Now the issue is that the concrete slab is horribly uneven and is in dire need of a few bags of self leveller. The one I usually use is Mapei Ultraplan Renovation Screed.
My concern is that this will flow over the top of the 110-40mm reducer and will seal around the little 40mm spigot.
Now being sensible, I can't actually see anything wrong with that. The reducer is a push fit, so the rubber ring will be hidden well away from the levelling compound so I shouldn't need to worry about chemical issues. Similarly, the levelling compound will lock the reducer in place so should logically help rather than hinder the seal. Plus it'll look very neat.
I'm on a one-house septic system so don't need to worry about the sewers backing up - and if I ever did need to access it, I could chip the leveller out of the way.
Does this seem OK to everyone else? I do still have a lingering unease about cocooning a plastic fitting.
The only alternatives I can see are either to extend the pipe up a few inches and reduce from there - but there'd still be a joint underground and if anything, there'd be a chance the stub could act as a lever on the joint when knocked. Or I could put a ring around the waste pipe to act as shuttering when I self level, but this would create a pair of odd sumps in the room.