I am trying to seal my old hot air heating/air conditioning ducts. I was
told not to use the traditional duct tape, but to use special tape and
mastic. My ducts are the flexible type, with a thin layer of insulation.

I found several kinds of metal tape at the HD. Are they all suitable for
heating systems? The assistant did not have a clue.

I did not find any mastic at the HD. Any recommendation for the mastic and
where to buy it?

Thanks

--
Walter
www.rationality.net
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