Sanitary T w/ L & R Side Inlet

I found this fitting in a catalog and it seems like it could solve the problem of feeding a W.C., shower drain and lavatory drain into a stack (on a second floor bath) with only a slight drop to the cieling below. I did not want to notch or dirll the joists for pipe so keeping all of the entry points into the stack in the same horizontal plane is most desirable. Above this fitting the stack will be dry (only vent to roof).

Is this the correct use for this fitting? It just seems a little odd having drain flows directly opposing each other as they enter the stack.

fitting

It is the correct fitting, but many inspectors will reject it. It is no different than the fitting used to connect two sinks to the same riser, as long as the riser is properly oversized to prevent crossover flow.

I just had to replace one of these the other day. It was ABS, which no one stocks around here. The left side 1-1/2" hub had cracked. It was in a 3 story apt. building which settled a little bit. The stress cracked the hub. I used a PVC fitting and tangents and tied into the ABS with shielded couplings. I think the rubber will allow for any additional settling or stress.