Fan and vent sizing to cool a greenhouse on hot days.
Greenhouse volume is multiplied by an air-exchange rate that grows with the temperature rise to be overcome. Undersized fans bake seedlings when the sun peaks, while oversized ones waste power on mild days.
Greenhouse Cooling
Volume = L x W x H; CFM = volume x (1 + rise/20)
Volume = L x W x H; CFM = volume x (1 + rise/20) Greenhouse volume is multiplied by an air-exchange rate that grows with the temperature rise to be overcome.
Undersized fans bake seedlings when the sun peaks, while oversized ones waste power on mild days.
This calculator takes 4 inputs: Length, Width, Average height, Temp rise to handle. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.