Heating, Air Conditioning, Fridge, HVAC/Duct insulation



Thank you for taking the time to help. I have an attached garage with a family room above. I have an 8"x12"x18' duct line that feeds the family room. This duct is not insulated (I checked inside for insulation as well). In the spring I am going to gut the garage and insulate with foam board and drywall. I would like to temporarily wrap it with something to help prevent heat loss for this winter. Because of the construction of the garage, I can't access the top of the duct. I could wrap it in regular fiberglass insulation, but this would be time consuming and not too attractive. Is there a product that will give me the "U" shape I need to cover the 18' run even if I have to cut it to fit? Thank you.

Sorry for the delay, I was on vacation for the holiday and forgot to put myself on vacation.

There are two options I can think of.
One is to use fiberglass duct board and seal the ends with mastic.  You can use stick pins to  keep the board in place on the duct.
The second would be to get sheets of Rubatex type insulation.  It is the same stuff used on pipes, but comes in rolls and sheets.  You can glue it on the duct with Rubatex glue.  It is easy to cut with a sharp knife or blade.  Unlike fiberglass, it is not itchy to work with.


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Craig HVAC Expert


I have been in the HVAC field for the past 18 years. I can help with most HVAC questions. I work on commerical buildings for the most part, and have yet to find anything I could not troubleshoot and repair, when repairable. I work on small 1 ton units to a 2500 ton chiller. Troubleshoot air flow, elect, and control problems. I attend regular classes to keep up with the latest and greatest.


I work on commerical sites, hospitals, gov't buildings. I can troubleshoot just about anything in the HVAC business.

5 years trade school, VFD training classes, Liebert factory training, some York and Trane factory training.

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