I read the other thread by a similar name, didn't totally answer my question. Here goes .. I have a ~100yr old house with a cast iron main stack (4"). I'm adding a bathroom toilet/sink and need to tap into it. New stuff will be PVC (yes, I know about venting requirements, etc). 1) typical approach is to buy a saddle whereby you remove a 6" section or so. I don't really want to do that for several reasons -- chief among them not wanting to support 45 feet (3 10' floors, plus basement, plus roof part) of it when I do. 2) I'd prefer to cut an angled hole in it to allow the 3" PVC to enter at a 30 degree angle (that'd be an oblong hole). I'd cut the PVC accordingly so as not to introduce sharp edges inside the older pipe (thus providing a clog spot). 3) Seems the easiest way to cut a precise hole like this would be a plasma torch, although I've never tried using one on cast iron (works on 1/2" mild steel just fine though). I'm also concerned about intentionally introducing fire into a pipe which might contain methane. Should I haul a Co2 (or anything inert and heavier than air) tank up to the roof and backfill the pipe with gas to avoid a problem? Before I go buy a plasma torch ($1400) and test my theory, can someone tell me if I'm up the wrong creek here?
No announcement yet.
cutting into existing cast iron sewer pipe