There are three basic types of duct insulation: Duct board, duct liner and duct wrap. Duct Board. Duct board is used on the exterior of HVAC ducts and is typically fabricated in 1-, 1-½ or 2-inch ...

The duct board has AGM facing on one side and Foil-Scrim-Kraft (FSK) facing on the opposite side. The duct board is available in thicknesses of 1, 1.5, and 2 inches (2.5, 3.8, and 5 cm) in EI-475 and ...

The duct board is composed of resin-bonded glass fibers with a reinforced foil laminate air barrier vapor retarder facing applied ... and maximum internal pressures of ±2-inches (5-mm) water gauge.