Best Encapulation for Asbestos Tape on Ductwork

Curious if anyone has used or recommended use of encapsulation product on asbestos tape on duct work. I had a client really searching for answers and asked about 2 products. One is a paint and one is a spray. Any ideas on what would work best?

Duct mastic.

DO NOT get involved in this, other than to refer them to a Professional in the Asbestos abatement industry!!

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I know there is a fine line between being helpful and causing liability issues, but this is more of a personal question. I see this tape often and was curious if anyone knew generally how it is encapsulated. Whether with an actual EPA approved product, or if regular mastic is fine.

You would just use general mastic? Nothing that actually penetrates through the tape?


Good info from JJ:

No surprise (as always), but the very first question that should have been asked is…
“What is the current condition of the ACM that is being considered to be encapsulated”???

Sorry about that. The condition is actually really good. Hardly any area would be considered “friable” at this point.

So why all the fuss, leave it alone it won’t harm anyone. Stay out of any recommendations as others suggested when it comes to ACM’s.

Encapsulation at exterior will not help stop it getting into the vents which is from the interior side. It needs removal.

Bob, how do you figure encapsulation with the right material on the exterior of a duct will still pose a hazard on the interior?
First off, we don’t know the condition as Jeff mentioned, and second, we don’t have a picture, but inj my book, encapsulation means just that, whatever condition, it is buried and incapable of releasing any fibers airborne.

Here is a picture if it helps. It is in general good condition but rather than wait for it to become friable, it seems to make more sense to me to encapsulate now.

It’s taped at joints and the danger is circulation through air movement in the vents. Not just the outside. Ask an expert.

I’d have it properly removed.

Use this on the taped joints and then insulate the duct with a covering and good to go.
Don’t wait for it to become friable. It is not a problem now.
I am assuming that someone has tested it and confirmed it was an ACM.

Personally, I don’t think any type of ACM should be part of an air distribution system. I have seen plenty of ducts in my area that the metal was so rusted that the only thing holding the duct together was the white asbestos tape and insulation. It is one of those situations that I approach by saying: What if this was my daughter buying this home???

Do you think that sealant is just as good or better than an actual asbestos rated encapsulate? I have heard good things about Fiberlock brand Lag Kote 2. I would think it would be better to spend the extra money for that. Since paying to have it all removed isn’t feasible, my thought is that would be the next best thing.

but should be left to Professional people to repair as necessary. Although the duct and tape if at all ACM is in good condition, I would not recommend someone does that himself.

Ok thank you for your guidance!