Size ventilation fans for a greenhouse by air changes.
A greenhouse exchanges its whole air volume at a chosen rate, so the fan flow is the interior volume times air changes per minute. Proper ventilation pulls out the heat and humidity that otherwise stall growth and invite disease in a closed structure.
Greenhouse Ventilation
CFM = volume x air changes per minute; fans = CFM ÷ fan capacity
CFM = volume x air changes per minute; fans = CFM ÷ fan capacity A greenhouse exchanges its whole air volume at a chosen rate, so the fan flow is the interior volume times air changes per minute.
Proper ventilation pulls out the heat and humidity that otherwise stall growth and invite disease in a closed structure.
This calculator takes 5 inputs: Greenhouse length, Greenhouse width, Average height, Air changes per minute, Fan capacity. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.