Rockwool type insulation for rigid HVAC ducts?
aston01
| Posted in Mechanicals on
I am not the biggest fan of fiberglass insulation for rigid ducts mainly because of its compressibility. This has led me to keep an eye out for alternatives and I’ve see a few with Owens Corning’s Paroc being one of the more appealing options.
I’ve never seen products like this in person and I was curious if anyone here might have any insight into availability or issues with using products like this compared to fiberglass.
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Replies
The standard way to insulate rectangular ducts in the commercial world is to use a sort of compressed rigid fiberglass board with a white facing, which is usually attached to the ducts using a special fastener that looks like a nail with a wide washer-like head. The nails are poked through the fiberglass material and then tapped with an arc welder to weld them to the duct. You finish the job with a white seaming tape at the edges and at joints between panels.
There are also polyiso materials made for this application. I’ve never used polyiso for this application myself, but I suspect it installs in a similar way.
If you’re trying to insulate round ducts, I can’t think of any good options. You can get rigid fiberglass pipe insulation that is preformed into half circle shaped sections, but I don’t know if it would fit ductwork properly.
Bill