To vent or drain?

[Andrew]

I posted this to the plumbing and heating group as well:

I'm rehabbing a bathroom in my old victorian rowhouse in Philly, and I have a question about routing the drains for the tub and sink. Currently they drain into the cast-iron toilet bend which has two inlets on one side of it. The bathroom is on the second floor (of three) over the top of another apartment. I would like to change the configuration of things in the bathroom and route the drain pipes for the sink and tub down an existing chase in the wall directly to the basement where they would enter the main stack where it has been replaced with PVC. I don't have an easy way to route a vent for those two drains, however, so I'm wondering if I can drain to the stack in the basement but vent through the inlets to the toilet bend. Is this a totally non-compliant configuration? What sort of trouble would I have doing this? Any advice would be appreciated.

Also, I would like to move the toilet 90 degrees. Since the current cast iron ring has just two notches for mounting bolts, I want to replace it. But I don't have any experience working with cast iron. Is it just soldered on there? Can I heat it up, pop it off and stick another one on there? Thanks,

Andrew

[Speedy Jim]

I can only imagine the response from the "other" group!

No, you can't use the closet bend side inlets as venting.

Working with cast iron is *very* difficult. It's not soldered. Molten lead is poured into the joints and then tamped in place (calked).

You can use a PVC "expansion flange" which is designed to fit *inside* 4" CI. GOOGLE around.

Personally, I think you're asking for a lot of trouble re-working the whole design of the bath plumbing.

Hop down to the Philly library and dig out some old books on cast iron DWV practice. I'm sure they have something.

Jim

[buffalobill]

[Andrew]

...

I'm curious why I couldn't use the side inlets for venting. The house was designed to have a single vent at the top of the main stack, and everything--the kitchen and three baths--all drain into and vent from that stack. So, when the sink and tub were originally plugged into those side inlets they both drained and vented there. I'm proposing to just vent there and drain lower in the stack (in the basement).

I would much rather avoid reconfiguring the bathroom plumbing, but the current design is awful. When it was rehabbed in the 80s, someone sledgehammered a canyon into the original wet bed tile floor and ran a cobbled-together mixture of copper and PVC drain pipes through that canyon to the tub, and it actually *rises* between the tub and closet bend. No wonder I was always showering in a pool of water. To make matters worse, after backfilling the canyon, they drilled anchors into the floor so they could put down plywood and linoleum, puncturing the drain pipe in 4 separate locations...I know everyone's got a hard luck DIY story, but thanks for letting me 'vent'. Andrew