What is the best way to vent the plumbing for a 1 sink/1 toilet bathroom in the basement?

Question

I am currently finishing my basement, and we plan on putting in a small bathroom. When it comes to venting, I wasn't sure if I needed to run a pipe from the basement, up through the 1st floor wall, into the attic to meet up with the vent stack, or if there was an easier option. I have read a bit about studor vents, but I couldn't find in my local codes whether that was permissible for a toilet. Would I just be better off running the pipe to the attic?

Answer 1

Under IPC rules (which are the main code in my area, with a few modifications) you can join to a dry vent 6" above the flood rim of the highest fixture on the floor served which typically means somewhere in the 40-48" realm is safe, if you have a dry vent wit enough excess capacity you can access on the first floor level. Wet venting via a vented drain that does not have a toilet above may also be possible - there are limitations on it that are more restrictive than dry venting.

Evidently your local code is also based on IPC, with modifications that probably are different than my local modifications. The 2015 IPC which seems to be what your code is based on (but I have not tracked down your local modifcations.)

Air Admittance Valves (one common brand of which is Studor)(Mechanical Vent is another term you might see used for them in code) are permitted in IPC but may or may not be stricken in local code. I, personally, will always choose a real vent pipe connecting to an exterior vent over a device that can and does fail to work as intended and leaks sewer gas into the house until it's cleaned or replaced to restore correct function. You may do as you please if your local set of codes permits.