Rated 3.6 out of 5 by 35
Rated 5.0 out of 5.0 by crunchman This mastic works well
I am using this mastic to get all the duct work and plenum sealed prior to blowing insulation into my attic. This mastic product works well to seal HVAC duct work and the plenum. I planned on just sealing a couple seams on the plenum but after checking some of the flex duct connections, I decided to seal every connection from the plenum collar to the vent runs. (Check YouTube videos on "how to seal flex duct ") This will definitely stop the system from sucking dust out of the attic and blowing into my house and will increase overall HVAC efficiency.
This mastic works very well, applied with a 1" brush. Wear rubber gloves, gets messy. Water clean up.
November 11, 2014
Rated 5.0 out of 5.0 by trd2d Best at what it does!
For nearly a hundred year old home with some pretty old duct work, we were heating and cooling our basement as opposed to the rest of the home. Duct tapes didn't hold up well and new air leaks would form sooner than expected. The mastic did a great job at durably holding up and sealing. Since it was an unfinished basement space, we weren't so concerned with the, shall we say, less than aesthetically pleasing final look.
January 14, 2014
Rated 5.0 out of 5.0 by HotinTN Tough, tight duct sealant
I used this mastic to seal most of my HVAC duct. Simply brushed it on. It creates a very tight and tough seal. Obviously, it also locks the duct in place, i.e., 90 degree adjustable elbows. My only concern about the product is when I have had the occasion to replace duct work. I find the mastic has caused rust under it, but it seems to be surface rust . I hope it is not an ongoing process. Duct is so thin, I would prefer no rust but I haven't found an oil-based mastic. Do be aware that it can be fairly messy and even drippy so protect any finished surfaces nearby.
February 25, 2015
Rated 1.0 out of 5.0 by sheepslinky Totally inerfior mastic.
Go to an HVAC supply and get some professional mastic (or have it ordered). I got this junk on the weekend because HVAC place was closed. It'll take 4x as long to apply, has poor adhesion, shrinks, cracks, doesn't dry evenly, can't be worked into cracks well, and just seems cheap. It's also more expensive than the professional product I bought from HVAC supply house, which has UL 181 cert, LEED cert, and made my life so much easier. I will give it a "fair" on quality, though, as it would be far far better to use this mastic than the cheap tape out there (Butyl tape would have an edge, but not the foil faced acrylic tape...). I'm actually going to remove some of this stuff and do it over again with the good stuff...
November 29, 2014
Rated 5.0 out of 5.0 by u57629 Great Purchase
Easy to apply with my hands, a better visual for thickness of application is about a nickel thick. Does a great job.
January 31, 2015
Rated 5.0 out of 5.0 by Captain77450 Best Sealant Ever
I used this EXACT product from Home Depot in 1990 when I redid my condenser duct work. I used aluminum tape at the duct seams and then put on some rubber gloves and hand applied this over all the seams. It stuck to everything, metal, tape, foam insulation, etc. My A/C drip pan just rusted out 10/24/2013 and this stuff was STILL stuck tight and STILL flexible. I used a box cutter and cut this rubbery stuff and pulled on it HARD to get it off. This stuff is still GREAT after TWENTY THREE YEARS!!
October 24, 2013
Rated 5.0 out of 5.0 by SC1985 Easy to Use & Easy to Clean Up
Nice that it is water based to allow for easy cleanup.
February 26, 2015
Rated 2.0 out of 5.0 by cargraves Did not set
Mastic did not stick to duct work properly. Mastic appeared to adhere but then would slide off as if it were melting. Did not work for our needs.
December 13, 2014