Asbestos pipe insulation?

I had a client ask me what this was on some of his older pipes in his basement. Two pics show a black ‘tar’ type wrapping around his pipes, and the other two show some white fibrous materials that we suspect is Asbestos. Can anyone identify these materials?
Dave Strunk
Surety Home Inspections
Hackensack, Minnesota

Having it tested would be the only sure way to find out.
The white stuff looks like it, but I don’t recognize the blackish material.

Thanks Marcel.


prolly or similar

My guess would be that it probably contains some asbestos, see it fairly frequently in old houses here. Mostly they used it on elbows or around fittings such as in your photo. Like Marcel says the only way to know is lab testing.
The straight runs are more often just corrugated fiberboard insulation, at least that how it was done here.

You might want to see if your state requires licensing or certification to take samples.
Once you do take a sample you just ship it to a lab for testing.
I use EMSL.

The rope is most likely asbestos as is the joint insulation.

The black stuff looks suspiciously like oakum, which was mostly -but not only - used as sealant for waste pipes, especially cast iron. Oakum is some sort of felt with tar.

Hard to say from the pictures

Thank you everybody for your replies. I gave the homeowner a list of state certified asbestos contractors and they will take it from here.

Modern oakum is from virgin hemp or jute with pine tar. Jute is used to make burlap also.


Thanks for the info. I didn’t know oakum is still being made. I only see it in old houses, and not too often at that.

The best way to go around it is to have samples tested in a lab. The white one looks suspiciously like asbestos, but it’s hard to tell from the picture to be certain.

Still used in other industries. :smiley: