The answer to 'how to fix air duct sealing' is to properly seal and insulate your home's air ducts. This helps improve energy efficiency, reduce air leaks, and maintain proper airflow throughout your HVAC system. Proper duct sealing involves using mastic sealant or metal-backed tape to cover any gaps, cracks, or joints in the ductwork.
Start by inspecting your ductwork, looking for any visible gaps or leaks. Clean the surfaces with a degreasing agent before applying the sealant. Use a paintable mastic sealant or metal-backed tape designed for HVAC applications, and apply it evenly over the joints and seams. Make sure to seal all connections, including where the ducts meet the walls, floors, or ceilings. For best results, also insulate the ductwork to prevent energy loss.