Insulating Ducts
After creating a conditioned space in the attic, attic duct insulation is the most effective thing you can do to make a big difference in the comfort of your home. Ducts need the most insulation on top, where they get pounded with radiant heat from the roof in summer and are exposed above the R60 cellulose we install.
SilverGlo and Spray Foam
2" SilverGlo is laid on top of the trunk line of the duct. Then, the sides are spray foamed, sealing along the edge of the SilverGlo. The sides only need 1" of spray foam and need even less lower down. This is necessary to air seal where the ducts will be buried in cellulose.
SilverGlo is Cost Effective
SilverGlo costs $.35 a board foot compared to $1.50 for a 200 board foot kit, $.1.05 for a 600 board foot kit or $.88 for refillable foam. So let's say you laid 2" SilverGlo on top of the trunk ducts radiant barrier up, and then spayed the sides and bottom of the ducts. You'd save about $1.20 for each square foot of SilverGlo you install!
