Ducts Buried in Attic Insulation and Encapsulated Description This guide describes approaches to buryng and encapsulating ducts in unconditioned attics to increase the overall R-value of duct insulation.
Unvented Conditioned Attic with Spray Foam Insulation Below Roof Deck Description Guide describing a method for insulating an unvented attic by spraying foam insulation along the underside of the roof deck.