I am installing a basement bathroom and want to make sure I properly vent. I need to tap into a 4" drainpipe that runs across the basement floor. This pipe provides drainage to a 1/2 bath on first floor, and runs across basement floor to the main stack that drains upstairs bathrooms and kitchen, and vents out to the roof. The bathroom is to be installed in the corner of the basement where the pipe comes down from the 1/2 bath. This pipe goes to that bath but does not vent out to the roof.
So, I need to put three Wyes into this 4" inch floor pipe. One 3" Wye that will run to the toilet, one 1.5" or 2" Wye that will run to the sink, and one 2" Wye that will run to the shower drain. Toilet is within 3' of sink, and shower drain is within 8' of sink.
Given that background, which I hope makes sense, I have been told various things on venting: (1) Given the nature of this floor pipe, which ultimately connects to the house's main vent stack (about 15' away from bathroom location), that I don't need to provide extra venting at all in this basement bath; (2) That I need to pursue much more complicated venting of each drain (toilet, sink, shower); and (3) That I could put one AAV (mini studorvent) in the sink cabinet, on sink drain pipe, and that AAV will provide sufficient venting for the whole bathroom. I like option 1 but it seems too good to be true. I like option 3 as well.
What do you think of these options? Thank you for any guidance you may have.
So, I need to put three Wyes into this 4" inch floor pipe. One 3" Wye that will run to the toilet, one 1.5" or 2" Wye that will run to the sink, and one 2" Wye that will run to the shower drain. Toilet is within 3' of sink, and shower drain is within 8' of sink.
Given that background, which I hope makes sense, I have been told various things on venting: (1) Given the nature of this floor pipe, which ultimately connects to the house's main vent stack (about 15' away from bathroom location), that I don't need to provide extra venting at all in this basement bath; (2) That I need to pursue much more complicated venting of each drain (toilet, sink, shower); and (3) That I could put one AAV (mini studorvent) in the sink cabinet, on sink drain pipe, and that AAV will provide sufficient venting for the whole bathroom. I like option 1 but it seems too good to be true. I like option 3 as well.
What do you think of these options? Thank you for any guidance you may have.
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