Should you replace 20 year old ductwork?

Deciding whether to replace residential heating and cooling ductwork that has reached twenty years of age depends heavily on the physical condition of the materials, the presence of sagging or collapsed runs, and the extent of insulation decay. Flexible plastic ducting and fiberglass duct board typically degrade, crack, and lose structural integrity after fifteen to twenty years, especially when exposed to extreme attic heat cycles or rodent damage. If your twenty-year-old ducts show widespread tearing, heavy mold growth inside the liner, or severe leakage that cannot be fixed by standard mastic sealing, full replacement is often necessary to restore indoor air quality and system efficiency. You can troubleshoot by having a professional inspect your duct runs with a camera. You can verify that replacement is required when chronic comfort issues persist despite servicing.