Soil Pipe

We have a corroded soil pipe in our basement. How difficult is this to fix?

The house is 100 years old, and the current soil pipe is made from cast iron, I believe. We're afraid that we may end up tearing up walls in our house to replace with PVC. Is there any easier, less expensive way to fix this problem?
Well, we had the house inspected and the inspector seems to think it's corroded right a the basement level, which is exposed. I'm not sure about the extent of the corrosion, but I know that we're afraid that if it's corroded there, when we go to replace it, it may crumble all the way up the wall.

You don't mention the extent of the deterioration. The soil stack that rises up vertically may have connections from fixtures on each floor. If you don't have leaks tracking down this vertical section, leave it alone. If the exposed potion in your basement is leaking then you could replace it with PVC or ABS piping. If you do have leaks in the walls you don't have other options. Opening some portions of walls, ceilings and or flooring may have to be done. It is hard to estimate how much without actually seeing the problem. I recommend getting an estimate from a few plumbers. This will give you an idea of what your expences might be and also if it is something that you might not want to tackle yourself.
I have seen leaks that apeared to be a leaking stack, but actually came from a deteriorated tub drain that tracked down the soil pipe and repaired much cheaper than replacing the entire soil pipe. You need to determine the exact nature of your problem and then make a plan for repairs. hope this info helps.

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