Which is a characteristic of infiltration in building structures?

Infiltration in building structures refers to the unintended and uncontrolled movement of outdoor air into a building through cracks, openings, and other unsealed areas. One of the primary characteristics of infiltration is decreased energy efficiency. This occurs because infiltrated air can lead to a loss of conditioned air (heated or cooled air), which forces heating or cooling systems to work harder to maintain the desired indoor temperature. As a result, energy consumption increases, leading to higher utility bills and reduced overall energy efficiency for the building.

While other options may suggest potential benefits like improved air quality or enhanced ventilation, those are typically associated with controlled air exchange rather than uncontrolled infiltration. In fact, uncontrolled air infiltration can contribute to discomfort and inefficiency rather than promoting consistent and balanced indoor conditions. Therefore, decreased energy efficiency is a defining consequence of infiltration in building structures.