As part of a basement remodel I'm planning out the rough-in for adding a bath on slab, residential dwelling. I'm going to connect a lav drain line line to an existing below slab 2" PVC buried line. I'll be adding a 2" horizontal 'Y' to the existing line and I've heard PVC repair couplings are notorious for not getting a water tight weld. I'm checking with the city if I can use shielded couplings.
Alternatively, although I hate adding four 90 degree sweeps to a horizontal line, I could reroute the line to accomodate the new fitting as in the attached drawing? The existing 2" line services only a single bar sink.
thanks for any advice