CFM in HVAC stands for cubic feet per minute, which is a measurement of airflow volume. It is used to determine the cooling requirements of a building and, in turn, its HVAC system capacity. CFM is important because having an accurate estimate of a buildings CFM is key to choosing an HVAC system with the right capacity for the space and needs. Too much or too little airflow can negatively impact system performance and even cause damage to its components.

HVAC professionals calculate CFM in two different ways. One way is to calculate the ventilation requirements of the space based on its size and the frequency with which the air needs to be exchanged. The other is to calculate the capacity of the system based on its power, which is measured in tons, and the volume of the entire space it is ventilating.

A qualified HVAC dealer will calculate a buildings CFM and take into account various factors such as the number of windows, climate, and even temperature preferences to determine the appropriate system capacity. A typical air conditioning system produces 350 CFM - 400 CFM per ton of air conditioning.