I am in the process of installing a bathroom over an existing slab. The floor joists are 2x8pt. I have approx 5 1/2" of space between the top of the slab & the bottom of the joist. I want to run the 3" drain line through the outside wall, 90 down 10"(w/ a cleanout on top), then 90 out to the 4" line going to the septic tank. Is this acceptable or do I have to break up the slab inside the wall, go under/through the foundation and 45 or 22 out to the 4" line?
Thank you in advance for your assistance,
B-tine

I would say go ahead except for the dogleg you wish to install with the two 90's. Is there any way you can get around this? Regards, Tom