Expose the ceiling finish approximately 12" on both sides of the duct. Remove existing duct insulation if present and set aside for re-use.Install tape at joints and penetrations in the duct.Install spray foam or sealant around the duct penetration at the ceiling finish.Install duct insulation or new insulation sleeve along the whole length of the duct inside the attic. The duct insulation should be at least 2" thick.Replace existing insulation and, if desired, install additional insulation.
