My 2 inch bathtub drain runs 7 feet perpendicular to the 3 inch toilet line and feeds in to the top of a 3 inch with a 2 inch Y. The drain line is at a 1 inch drop. I need to vent the bath within 5 feet of the tub to satisfy code (it will also double as a wet vent for the toilet), but at the 5 foot mark there is not enough room in the joist to accommodate a 90 out of the top. I would also preffer the vent closer to the tub.

Can I tee out 90� on the same plane as the drain and then go up the wall? Or does the vent need to leave the drain through the top? What about using a 2 inch Y at an angle and a 45� and 22.5� to straighten the pipe? Keeping in mind at no point wount the vent line ever be lower than the drain.

The toilet says max vent distance is 9 feet. Does the point the tub drain enters the 3 inch does that count as the (wet) vent point or is it at the point the vent comes off the tub drain? I suspect the former.

Edit: went with a T off set at 45ð with a 45ð to send it through the joist at a slight grade. It then 90s and conects to a vertical to the attic that runs though a crawl space to the stack.

This post was edited by Noctua on Sat, Jan 18, 14 at 20:38