basement drains - vents needed?
I am in the early stages of planning to finish my basement. I had the builder rough in 3 sink drains and a powder room toilet drain.
The question i have is - do all 4 of these drains need to be tied to an air vent?
It looks like the plumber installed a single vent pipe for the basement. He located this vent in the center of the basement and it is capped off up in the ceiling joist, extending about 4 inches down.
2 of the sinks are about 20 to 30 feet away from the capped vent location. I am assuming that both of these drains will need to be vented and I can run 1 vent line and use 2 T's to provide venting for these.
The powder room sink drain and powder room toilet drain are close to each other. Do both of these drains need their own vents? Can i use the single vent in the beasement to service all 4 of these drains?