The answer to 'lifespan of air duct sealing' is that properly installed and maintained air duct sealing can last 10-20 years or more. Air duct sealing involves applying a sealant or mastic to the joints and connections in your ductwork to prevent air leaks. This helps improve the efficiency of your HVAC system by ensuring the conditioned air is delivered where it's needed.
The longevity of air duct sealing depends on factors like the quality of the materials used, how well the sealing was done, and the environment the ductwork is in. Ductwork in attics or crawl spaces may need resealing sooner than ductwork inside the home's conditioned space. Regular HVAC system maintenance and inspections can help identify any areas that need resealing before major leaks develop.