The characteristic describes a building’s resistance to unintended airflow through gaps, cracks, and other penetrations in its envelope. It signifies how well a structure prevents outside air from leaking in and conditioned inside air from escaping. A home with a high level of this characteristic minimizes uncontrolled ventilation.
Maintaining a defined standard offers numerous advantages. It enhances energy efficiency by reducing the workload on heating and cooling systems. It improves indoor environmental quality by limiting the entry of pollutants, allergens, and moisture. Furthermore, it contributes to occupant comfort by minimizing drafts and temperature fluctuations. Historically, construction practices often neglected this aspect, leading to significant energy waste; modern building codes increasingly emphasize its importance.
