Antonio4791
New Member
Hi all, I just built a 2x6 stud wall for my new bathroom. I would like to put in a 4 inch vent pipe but I'm wondering if 4 inches is too wide. Obviously there are code issues with boring studs, but what about top and bottom plates? This is a load bearing, double top plate wall. A 2x6 is only 5.5 inches wide and the OD for "4" inch DWV pipe is 4.5 inches, leaving only a half inch on each side of the plates. That seems too big to me. I suppose I can get by with 3 inch. I would like to do to the toilet drain with 4 inch and would like to have the vent be the same size. Is it OK to have toilet drain by 4 inch and the vent be 3 inch?