How many CFM of fresh air ventilation is required per square foot in a commercial kitchen?

# Commercial Kitchen Ventilation Requirements

Commercial kitchens typically need 0.7 to 1.5 CFM (cubic feet per minute) per square foot of kitchen area, though this varies based on several factors:

Key Variables: - Equipment type & intensity: High-heat equipment (fryers, grills, woks) requires more ventilation than prep areas - Local codes: Requirements differ by jurisdiction—some areas require 1 CFM/sq ft minimum, others up to 2+ CFM/sq ft - Make-up air needs: You need enough fresh air replacement to compensate for exhaust (typically 80-100% of exhaust CFM) - Occupancy & cooking volume: Busier kitchens with more equipment need higher rates

Design Standards: Most commercial kitchens follow ASHRAE 62.1 (ventilation standards) and local building codes. A typical approach is to size exhaust hoods based on capture velocity and equipment, then ensure adequate fresh air supply.

Practical Example: A 1,000 sq ft kitchen might have 5,000-7,500 CFM of exhaust hood capacity, requiring 4,000-7,500 CFM of fresh make-up air supply.

My Recommendation: Work with a mechanical engineer or HVAC contractor who specializes in commercial kitchens—they'll assess your specific equipment layout, local codes, and efficiency goals (heat recovery systems can reduce make-up air costs). Undersizing creates negative pressure and poor performance; oversizing increases energy bills.

If you're in the US and need help finding a qualified HVAC or mechanical engineer in your area, engineers.city can connect you with local professionals experienced in commercial kitchen design.