Plumbing code question

you're ok. It's called a 'wet stack'.

steve

on 11/1/2007 9:21 AM Steve Barker said the following:

Aren't wet stacks only allowed on the same floor?

re: Aren't wet stacks only allowed on the same floor?

I hope not! My 2nd floor bathroom, 1st floor sink and 4 basement fixtures (full bath and utility sink) all use the same wet stack. There are no dedicated vents for any fixtures in my house.

The 1st and 2nd floor fixtures drain into the cast iron vertical stack and the basement fixtures all connect to the cast iron drain pipe under the slab. Everything works fine as far as I can tell. The only drainage problems I've ever had in 24 years were caused by roots in the town owned section of the drain out by the street.

I had the same setup and was required to update it to current code when I did some renovation last year. I had to move the downstairs vent so they connected into the stack above the point where the upstairs waste tied into the stack, so that water from above could not flow past the vents. It can be a small vent, I ran 1 1/2" PVC alongside the stack and reconnected in the attic.

If you are unable to extend vent to roof or above 2nd floor toilet, consider using a mechanical vent installed at the sink. Just remember to keep it accessible for inspection and maintenance.

Although not the best solution, it will work and may be permissible. Good question to ask your local plumbing inspector. Sometimes codes vary from locale to locale.