Duct Sealing

mgimbrere

I have an HVAC contractor who is a great technician and an apparently good system designer. He tells me that duct sealing is overrated and that sealing with metal tape is just as good as sealing with mastic. I continue to doubt him about this, but I am open to other professional's opinions.
What do you folks think? Thanks.

BrianfromPomona

I work in Commercial only, and 99% of the time we only use duct sealer, usually DP1010 or DP1020. I only use tape when i'm in a position that is tight, or where I will get wet with the duct sealer. In certain situations we will use regular duct tape, then seal over it with DP1010, which also works well.
I believe metal tape is good in certain situations such as connections at the furnace and on plenums, but if its on spiral or rectangular duct, tape wouldn't work and it would take longer. Metal Tape is code, so its as good when used correctly.

DuMass

I agree that the ducts should definitely be sealed at the time installation.
They are not going to get any tighter by themselves as time goes by!

jw05450

Duct sealer all the way. Its a cheap insurance policy to make sure you have a tight system.

beenthere

If its mastic tape, ok.

If its just silver tape, nope.

rjconstructs

I've only heard good things about duct sealer.