Can I use a saddle Pvc 3in to 3in cast iron or is there something else?

Hi Bikerbilly...

You can use a 3" PVC saddle on cast iron pipe (see picture).. it won't be a "code legal" connection, but it will work... see images.

If you want to be code compliant then you will need to install a 3" no-hub cast iron wye (or sanitary tee) fitting into the cast iron pipe using shielded clamps (see picture).

Cutting into a cast iron stack is a little tricky but can be done as long as you support the cast iron stack and you use the proper tools/safety equipment. Let us know if you want to discuss this more.. O.K.

What are you planning on installing? What is connected to the pipe above this connection you want to make? Finally, how do you plan to VENT this fixture?

Back to you...

MARK