What is the air change-over rate of a typical house?

The air change-over rate of a typical house generally falls between 1 to 2 air changes per hour. This means that in an average home, the air within the space is replaced one to two times every hour. This rate is influenced by factors such as the size of the house, the efficiency of heating and cooling systems, ventilation practices, and the overall tightness of the building envelope.

In contrast, much higher air change rates, such as 20 or more, are commonly associated with industrial environments or specialized facilities, which have significantly different ventilation requirements compared to residential settings. An air change rate of 30 or more, or even over 50, would typically indicate extremely high ventilation, often necessary in places where contaminants need to be rapidly diluted or removed, such as in laboratories or during certain manufacturing processes. Therefore, the choice indicating 1 to 2 accurately reflects the standard air change-over rate for a typical house, aligning with general building and ventilation guidelines for residential buildings.