I have just purchased a 1950's rental property with a cast iron vent stack. The insurance co. wants me to replace it as they are prone to leaking in older homes. The job seems fairly straight forward, but do you have to replace the elbow/cleanout at the bottom that is cemented into the basement floor or can you just replave from that fitting up?
I have also been reading that a 4" cast pipe can be replaced by a 3"pvc. It is a small home do I need to replace with 4"pvc or is 3" OK?

Thanks

Tom

You will have to check local codes to find out if you can reduce from 4 to 3" on your stack. In my area we are allowed to use 3" for the main stack in our new home construction. I shouldn't think that you will be forced to bust up cement and replace the bend at the base of the stack. On a side note, my house is 53 7years old with cast iron drainage but have had no leaks. As a vent stack carries no discharge or water was it "suggested" or "ordered" that you replace the cast iron with PVC? In my book you shouldn't have to unless there's a problem with the present stack.
Good luck, Tom

You will have to check local codes to find out if you can reduce from 4 to 3" on your stack. In my area we are allowed to use 3" for the main stack in our new home construction.

Thanks, I did check & you are right 3" is adequate

I shouldn't think that you will be forced to bust up cement and replace the bend at the base of the stack.

I will leave that part as is

On a side note, my house is 53 7years old with cast iron drainage but have had no leaks. As a vent stack carries no discharge or water was it "suggested" or "ordered" that you replace the cast iron with PVC? In my book you shouldn't have to unless there's a problem with the present stack.

That would seem reasonable, it was my insurance company who said that they want this done in order to keep my rates lower. As you noted, it does not carry water, so what the big deal is, I am not certain.
Good luck, Tom[/QUOTE]

Thanks