What process allows air to enter a house?

Infiltration refers to the process through which outside air enters a building through various openings, such as cracks and gaps in the structure, windows, doors, and other penetrations. This natural movement of air happens primarily due to pressure differences between the inside and outside of a house, which can be influenced by factors like wind, temperature, and the operation of ventilation systems.

Understanding infiltration is crucial for energy efficiency, indoor air quality, and overall building performance. It can lead to unwanted heat loss during winter or excessive heat gain during summer, affecting heating and cooling costs. Properly managing infiltration through sealing and using controlled ventilation systems can help enhance a home's energy efficiency and comfort.

The other options do not correctly describe the process of air entering a house. Exfiltration pertains to the process of air leaving the building, while aspiration and expiration primarily relate to breathing or airflow in biological contexts, rather than the movement of air in and out of a house.