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Firehawk734
May 17, 2010, 04:16 AM
I will be installing a full bathroom in the basement, and cutting up concrete to install plumbing.

Currently, I have a soil stack directly in the way of where the door to the bathroom will be going. This soil stack goes up to first floor (ranch home) and drains the 1/2 bathroom. The stack continues up through the roof as the vent.

What I plan to do, is cut this entire soil stack out completely. I wish there were a way to hide the stack and just tap into it, but there isn't due to the layout.

The question is coming. It seems that where I cut the stack out, I will need to cut out the connector in the main line and just rejoin the two pieces of horizontal main cast iron line. What can I use to rejoin those to make it one flowing piece of cast iron?

I also need to tap into the line a bit further down, maybe 3-4 feet, to run the drain line to the sink. Is there any worries with cutting two places into the pipe so close?

And, can someone diagram it or walk me through if I install a PVC WYE connector into a cast iron pipe, how should I go about this? I was thinking:

1. Cut about 12" of cast iron pipe section out.
2. Glue two short pieces of 4" PVC to a 4 x 4 x 2 (drain) WYE so that I end up with 12" from pipe end to pipe end, then use fernco couplings on each side to clamp the PVC on each side to the cast iron. Is this appropriate, and is there any other rubber booting needed here?

Do they make WYEs that are no hub so that you can cut a shorter section out and just apply clamps there or is that against code?

Thanks. I'm a newbie with plumbing and it has me nervous.

Milo Dolezal
May 17, 2010, 05:38 AM
You are on the right track. Yes, you can cut Cast Iron as many times as you need. Make sure you use proper support when cutting vertical Cast Iron. Cast Iron is heavy and upper portion will have tendency to drop down by its own weight.

Use shielded Fernco coupling to connect new (ABS/PVC) and old (Cast Iron). There are specific couplings that fit one side PVC and other side C.I.

Yes, they do make ABS / PVC "Y" that has now Hub on one end. It is called "Street Y". In Cast Iron, we don't use fittings with Hub ends anymore. So every fitting you purchase has ends that match diameter of pipe.

speedball1
May 17, 2010, 06:12 AM
Let me add a bit to Milios answer.

Make sure you use proper support when cutting vertical Cast Iron. Cast Iron is heavy and upper portion will have tendency to drop down by its own weight And here's how to support the stack when making a vertical cut, (see image).

Use shielded Fernco coupling to connect new (ABS/PVC) and old (Cast Iron). There are specific couplings that fit one side PVC and other side C.I. And here's what they look like, (see image)

Do they make WYEs that are no hub so that you can cut a shorter section out and just apply clamps there or is that against code?
Yes they make cast iron NO-Hub fittings, (see image)
Good luck, Tom

Firehawk734
May 17, 2010, 07:14 AM
That rubber sleeve, are those available at home depot?

Where can I get riser clamps? I was planning to start at the top and work downward, cutting maybe 12" sections at a time and handling it as I went. Is this too risky?

creahands
May 17, 2010, 07:58 AM
What are u using to cut CI?

If u use a saw, u will have to wedge 2nd cut as weight of pipe will bring pipe down and bind blade.

After supporting pipe make first cut at bottom. Make 2nd cut above. This will keep blade from binding.

Chuck

Firehawk734
May 17, 2010, 08:42 AM
I have access to a Sawsal with the right blade, but was also thinking to get a ratchet cutter, since that may be easier to control.

I also have a pneumatic cutoff tool that I would much rather use. Would this work for cutting Cast Iron?

millwright1
Jul 31, 2013, 11:40 AM
Sawzall will work fine but you need to use a abrasive blade sold at home depot regular metal cutting blades don't cut cast worth a darn nor does the abrasive blade cut galv pipe worth a darn any sawzall with under a 1 inch stroke might be a little slow. With the right blade each cut on a 4inch sch40 should take approx 3 min

massplumber2008
Jul 31, 2013, 12:31 PM
Millwright1 said, "with the right blade each cut on a 4inch sch40 should take approx 3 min"...

Since this thread addresses cutting CAST IRON I had to pop in and make it clear that cutting cast iron pipe, especially 4" (service weight or extra heavy) will take a lot longer using a sawzall than 3 minutes!

Even if you use the newer DIAMOND sawzall blades (made by lennox) you can be sure you'll be there for 10-20 minutes. Just FYI all!

Mark