3 16 or 5mm closed cell polyethylene foam covered on both sides with 0012 inch 0 03mm aluminum facing.
Foil backed bubble wrap insulation.
Double bubble reflective foil insulation 24 inch x 10 ft roll industrial strength commercial grade no tear radiant barrier wrap for weatherproofing attics windows garages rv s ducts more.
Prodex total is composed of 13 64 inch approx.
Most metallic bubble wraps are about an r 1.
These are the multifoil materials which include foil backed bubble wrap.
I have heard some say that the insulation could be installed loosely to maintain the gap.
Some insulation materials don t work 100 on trapped air.
Worth mentioning to get the equivalent r value to what the manufactures claim on the packaging the installer has to use spacers under the insulation to keep the prescribed air gap between the ducts and the foil.
Double bubble reflective foil insulation 24 inch x 10 ft roll industrial strength commercial grade no tear radiant barrier wrap for weatherproofing attics windows garages rv s ducts more.