I'm in the process of adding an additional bathroom on the 3rd floor of our house. My question is this, can I vent this bathroom into the 2nd floor bathroom vent, which about 10 feet away from my planned 3rd floor waste line? Are there any restrictions on how many horizontal feet versus vertical feet that the vent runs?

Thanks for any guidance you could provide.

speedball1

Yes, you may revent back into the 2nd. Floor vent and no there are no restrictions on horizontal vent lines. You are venting your bathroom group off the lavatory aren't you? Good luck. Tom