Leaking Cast Iron Waste Pipe Damage
This is the perfect picture of what a leaking cast-iron
waste pipe looks like. If you notice the rest of the pipe is black,
except for the damaged areas that are rusting.
I would like to point something out here that's very important. Just because you find rust on your cast-iron waste pipe, doesn't mean that it's leaking. In a situation like the picture above, most of the pipe is black with very little rust.
If this is the case, there's a good chance that you have a water leak problem. If the entire cast-iron waste pipe is rusted, the pipe itself could be exposed to moisture. We usually find these conditions underneath the house or in your crawlspace area.
The upper arrow is pointing to rust that's bulging out of the cast-iron. This could be a manufacturers defect or the pipe was damaged before, during or after installation.
The bottom arrow is pointing to a spot where water can accumulate for long periods of time, causing additional damage to your cast-iron waste pipes.
Home Repair Tip: The damaged section of the cast-iron waste pipe drain should be removed and replaced. Working with cast-iron isn't going to be as easy as working with plastic drainpipes.
If you don't know much about cast-iron waste pipes, it wouldn't be a bad time to learn more about them or hire a licensed plumbing contractor who does.
Water damage like this to your plumbing pipes is only going to get bigger, something like this normally doesn't go away all by itself.