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how do you connecct pvc to cast iron drain pipe

i am replacing the old drain pipe, which is leaking with pvc but i do not know how to cut the cast iron and how to connect the new pvc to the old cast iron that exits the house. i want to cut the BIG pipe and it is up at the ceiling on first floor it is well rusted so i have to cut it. i need a safe way to cut the pipe. HELP!!!! FYI i live in wi. for code. Thanks for your time.

Re: how do you connecct pvc to cast iron drain pipe

This is done with what's known as a Fernco Fitting; it is a black neophrene fitting that will slip over the newly cut cast iron pipe and take the new PVC pipe on the other side; the Fernco comes with 2 stainless steel metal bands that are then tightened to secure the FF to the pipe.

You will have to get the exact outside diameter dimension of the cast iron pipe & of the PVC pipe so you know which size Fernco to buy; they come in all different sizes.

You would first have to FIRMLY BRACE the cast iron pipe with steel bracing against the ceiling so you could cut a small section out, so you can fit the fernco in; use a 7" circular saw fitted with a 7" metal-cutting blade to make your cut; make sure you wear safety glasses and wear a long-sleeve shirt to protect yourself from flying sparks & metal particles.

Smear some axle grease on the pipe ends to ease installation before attempting to fit the Fernco onto the pipe ends.

Fernco fittings are carried by Home Depot/Lowe's or any plumbing supply house.

Re: how do you connecct pvc to cast iron drain pipe

Yes you can use a power saw or grinder with a metal cutoff blade but they are noisey --- it's messy -- and potential fire hazard from sparks flying.

To be honest --- go rent a soil pipe cutter it's quick , no noise , no mess.

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