Fan Airflow Calculator

CFM stands for Cubic Feet per Minute, measuring air volume flow rate. Calculate CFM using: CFM = (Room Volume × Air Changes per Hour) ÷ 60. This determines how much air needs to move through your space each minute for proper ventilation.

For a 2000 sq ft home with 8 ft ceilings, you typically need 1,600-2,400 CFM depending on the room types. Living areas need 6 ACH, kitchens need 15 ACH, and bathrooms need 8 ACH. Use this calculator to get precise requirements for each room.

ACH varies by room type: Living rooms (6 ACH), Bedrooms (4 ACH), Kitchens (15 ACH), Bathrooms (8 ACH), Offices (6 ACH), and Workshops (10 ACH). Higher ACH means more frequent air replacement for better ventilation.

Good CFM depends on your space and use. Residential rooms typically need 0.35-1 CFM per square foot. Commercial spaces may need 15-20 CFM per person. The key is matching CFM to your specific ventilation requirements and room usage.

Safety factors (typically 15-20%) account for system inefficiencies, duct losses, filter resistance, and aging equipment. This ensures your fan can maintain proper airflow even under less-than-ideal conditions.

Static pressure is the resistance your fan must overcome in the ductwork and ventilation system. Higher static pressure requires more powerful fans. Typical residential systems have 0.1-0.5 inches of water column static pressure.

This calculator works for basic industrial spaces, but complex industrial ventilation may require additional factors like heat load, contaminant removal, and specific air quality standards. Consult an HVAC engineer for critical industrial applications.

Common conversions: 1 CFM = 1.7 m³/h, 1 CFM = 0.47 L/s. For international units, multiply CFM by 1.7 to get cubic meters per hour, or by 0.47 to get liters per second.