Adding a clean-out to old cast iron and/or clay pipe

[Ben Skove]

Hi everyone,

I'm in a 110 year old house and looking to do a relatively temporary fix. The fixtures tying into one stack in the house are nearly unusable due to a clog which appears to be located near the basement. The fixtures which tie into this stack are a 2nd floor toilet and a 1st floor sink. The clog is located beneath the tie in with the sink, and allows slow drainage; however, with even more than rare use there is backup from the toilet into the sink. Unfortunately, there are no clean outs for this stack whatsoever, and the last plumber attempted to clear the clog by popping the toilet and running his auger from there. He was unsuccessful, but believed he got as far as the bend at the bottom of the stack. He believed he was pulling up roots with his attempts. He then quoted a several thousand dollar job to replace the cast-iron stack with PVC from the basement to the toilet; however, he didn't include any estimate for ensuring that the clog was also removed.

The cast iron is clearly in bad shape, rust barnacles and all, and will need to be replaced before too long. However, that's beyond our budget right now. My hope is that now that I've made the basement pipes accessible so that a PVC cleanout can be tied in with some fernco couplings, the clog can be removed and peace restored for at least a while. I'm planning on doing the grunt work myself and let a plumber do the pipe work - the cast iron is in bad shape. I'd like feedback so that I know what I'm talking about and what options I should discuss in getting this done.

There are two possibilities. The first is to tie it into the cast iron in the wall. I'm concerned about the amount of weight on the stack (it's a three story house, and it isn't clear where the nearest support for the stack is above the basement level), as well as whether snapping/cutting into the cast iron is going to cause enough shaking to the stack to create problems in other hubs above, given their condition. I've also busted through the concrete floor and excavated down to what appears to be clay pipe that connects to the stack, so the second possibility is putting a clean out there.

Here is the cast iron stack:
http://www.flickr.com/photos/4888905...01/8239135480/

Here is the stack / clay pipe in floor:
http://www.flickr.com/photos/4888905...01/8238069481/

Here is the pipe in the floor. The other branch appears to drain a separate stack consisting of a basement toilet and 2nd floor sink and tub. None of these have problems draining.
http://www.flickr.com/photos/4888905...01/8238064889/

Thanks for your options and opinions!

[tjbaudio]

My gut says the elbo is broken under the floor. Can you add a support at the top of the block wall? If so I would do that before excivating any more soil/cement. Be carful you don't undermine the foundation. Also from what I read using a chain break on that kind of pipe is risky at best. Hard to get a clean cut with out it fracturing.

[hj]

Since the cast iron is recessed into the wall, cutting it would be difficult, although that would be an ideal location for a CAST IRON cleanout, not a plastic one. Supporting the pipe would not even be a consideration before cutting it. But a plumber could EASILY install a cleanout in the clay pipe and extend it up to the floor level. It would also be easy to remove the clay elbow and change to cast iron up to the point where the new cleanout is installed.

[Ben Skove]

Unfortunately, the stone foundation is topped by the brick exterior wall - there's no ledge to sit a support on. The stack is recessed into a chase that goes straight up, and it's not clear how far up the first support is. Some chiseling into the stone/brick would be necessary to add a riser clamp. Additional pics of the top part of the stack as it goes upwards:

http://www.flickr.com/photos/4888905...01/8242254218/

http://www.flickr.com/photos/4888905...01/8242255776/

HJ - wouldn't the stack still need support prior to being cut? Even though it's recessed into the wall, it's free standing. I worry about the amount of weight in that column! That's why I was thinking along the lines of what you said - run a cleanout from the clay to floor level.

tj - i agree with the pipe being hard to cut w/o fracturing...that's why I'd like to leave that portion of the job to an experienced plumber if possible.