Construction
Air Changes Per Hour Calculator
Air changes per hour — fundamental to ventilation design. Commercial spaces and labs have minimum ACH requirements.
Air changes/hr
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- Room volume (cu ft)
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- Minutes per AC
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- Use class
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FAQ
Typical residential ACH? +
0.3-0.5 ACH from infiltration in a tight home; 5-6 ACH with active mechanical ventilation; 8+ ACH in kitchens during cooking.
Commercial ASHRAE minimums? +
Office 4 ACH, classroom 4 ACH, exam room 6 ACH, operating room 20 ACH. Verify with ASHRAE 62.1.