What device can help reduce duct leakage in a building?

Duct sealant is the most effective choice for reducing duct leakage in a building. Duct leakage can significantly impair the efficiency of an HVAC system, leading to energy loss and increased utility bills. When applied appropriately, duct sealant fills gaps and cracks in the ductwork, preventing conditioned air from escaping into unconditioned spaces. This helps to maintain proper airflow throughout the system, enhances overall energy efficiency, and improves indoor air quality.

In contrast, while insulation material can help minimize heat loss or gain in ductwork, it does not directly address the leaks themselves. HVAC filters are important for maintaining air quality and protecting the system, but they do not prevent duct leakage. Air purifiers focus on filtering out particulates and pollutants from the air inside a building but have no impact on duct leakage. Thus, duct sealant directly addresses the root cause of air loss in duct systems, making it the best option in this scenario.