Should the plenum be insulated?
Besides, does ductwork need to be insulated?
Insulation is applied to ductwork to enhance thermal performance and prevent condensation and dripping. Return air ducts only need to be insulated if they pass through environments that adversely affect the return air temperature. Exhaust air ducts normally do not need insulation.
Besides, what is insulated ducting used for?
Insulating ducts in unconditioned areas of the home can help reduce space heating and cooling energy costs and improve indoor comfort. In humid climates, properly installed duct insulation can also reduce moisture condensation on metal ducts.
Galvanized steel and aluminum are the most common materials for sheet metal ducts. Aluminum in particular is relatively light and easy to install. They are also the least likely to harbor dangerous molds or growths because they have non-porous surfaces.