Moving sink next to toilet - help with connecting waste

[hztm2008]

Hi, would really appreciate your advice. We currently have a soil pipe running up in the corner of bathroom. There is a pipe coming out one side for the toilet waste and a pipe coming out the other side for the waste from the sink/bath. I have attached a picture. We are replacing the bath with a walk in shower and need to move the sink to the other wall next to the toilet.

I was thinking that we could run the waste for the sink under the floorboards and into the soil pipe (the joists are running the correct way for this) but the plumber has said that this is not how it should be done, and we would need to connect above the floor. He said that we would need to connect a waste pipe from the sink to the toilet connector or into the pipe between the toilet and the soil pipe. Does this sound correct? This is not going to look very nice because the connecting pipe would need to be quite high up if it needs to go into the toilet connector? He has recommended that we either put a run of furniture in to hide the pipework or build a stud wall with a concealed cistern. We did not really want to go to the cost of extra furniture so would really appreciate any advice on how you normally connect this sort of thing.

Thank you very much indeed.

 

[Hugh Jaleak]

I dont see an issue with it, provided the sink waste can connect at a point where there wont be any issues with crossflow from the WC, and if it's entering the same side of the stack, then that would be ok. Possibly Plumber looking for an easy option.