I recently moved into a year old home that has an unfinished basement. There are rough-ins for a toilet, shower and sink already in place. My questions is what venting needs to be added for these rough-ins or are these vented through the existing plumbing already (or how can I tell)?

I recently moved into a year old home that has an unfinished basement. There are rough-ins for a toilet, shower and sink already in place. My questions is what venting needs to be added for these rough-ins or are these vented through the existing plumbing already (or how can I tell)?

If there' a pipe running up through the roof from the tee that stubs out the lavatory the basement group is vented. If no pipe up from the lavatory you must run a regular vent or or install a mechanical one. Good luck, Tom