Hi everyone.

When we bought our duplex, the home inspector said that we would need to re-seal the soil stack some time soon. Well, I've finally come to that point in my home project listing, so I wanted to find out what I should use to seal it and if there is anything I need to be aware of when doing it.

The soil stack appears to be made of iron (house was built in 1954).

Any thoughts?

Thanks for your help!

Seal it where? At the roof penetration, the foundation penetration, or at each joint in the CI stack?

Answer Reds questions. You have cast iron drainage. Would the inspector be asking you to reseal a cleanout tee? Talk to us, Tom

You'll have to forgive me. I'm a little new at this plumbing stuff!

The stack in the basement going into the foundation.

Thanks!

Is this a joint that leaks? A break in the pipe? A falty fitting? Or is there a gap in the cement around the stack the inspector wants caulked? Give us something to work with here. Regards, Tom

All I know is that he said that the seals were old and should be replaced. I think it's the actual seals on the stack. There is no gap and no cracks or leaks.

Thanks!

You stack seals are as old as the stack and that does not automatically mean they need replacement. The age of the home tells me its likely sealed with oakum and hot lead. Inspect the rim of the seal, if the lead is in place you should start to question everything else that inspector may have told you.

Seems to me that the inspector may have been suggesting that you may need to repack/caulk the lead joints again sometime in the future.

If that is his suggestion... maybe it is necessary... maybe it's not!

If seeing wettness/leak then abviously you need to repack joints with the proper caulking irons (can be purchased at home supply store or plumbing supply house... see pic.)

If no leak.. then no issue... lead/oakum joints look messy sometimes... may even have an oily residue around the joints... but that does not make it a leak!

If you need to repack joints can use packing irons (inside and outside caulking irons) but be VERY careful as you can overpack the lead and CRACK THE HUB of the cast iron pipe... see picture.

Be especially careful at any joints near the foundation... in fact, I would call a professional plumber in to repack these joints if they are anywhere near the foundation! One mistake at the foundation pipe could mean that you are digging up the pipe UNDER the foundation and in the front yard...so think about that before proceeding!!

Anyway, let us know what you think...

Mark