I have a plumber putting in new pipes for a bathroom in a house that is up on block. He says the shower, toilet and sink and the kitchen plumbing pipes can all be vented under the cabinet and do not need an extra vent stack. Is this true? It is an old house and originally had on vent stack for the shower and another for the toilet these were cast iron and cracked and removed.

Hi Karen

ALL homes require a minimum of 1-3" vent stack to go through the roof...no exceptions that I am aware of. After the one vent stack goes out the roof then some states, not all, but some states will allow you to install mechanical vents (also called AAVs) for individual fixtures. These AAVs must remain accessible so they can be changed out in the future, if needed (just means they can't go in the wall and be covered over).

If you have any more doubts here, make a quick call over to the local building/plumbing department and ask them about minimum requirements regarding vents in your area!

Good luck!

Mark