Greenhouse Cooling
Fan and vent sizing to cool a greenhouse on hot days.
About Greenhouse Cooling
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.
Formula
Greenhouse Cooling
Volume = L x W x H; CFM = volume x (1 + rise/20)
- air exchange
- How many room volumes moved per minute
Worked example
With the default values below, Greenhouse Cooling returns Greenhouse Volume of 7,200. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Lengthminimum 1 ft
- 30 ft
- Widthminimum 1 ft
- 20 ft
- Average heightminimum 1 ft
- 12 ft
- Temp rise to handleminimum 0 F
- 25 F
Results
- Greenhouse Volume
- 7,200 cu ft
- Fan Capacity
- 16,200 cfm
- Fans (13k cfm)
- 2
Step by step
- 1Values used
- 2Greenhouse Cooling
- 3Greenhouse Volume= 7,200 cu ft
- 4Fan Capacity= 16,200 cfm
- 5Fans (13k cfm)= 2
Assumptions and limits
- The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to whole numbers, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How is Greenhouse Cooling calculated?
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.
Why does Greenhouse Cooling matter?
Undersized fans bake seedlings when the sun peaks, while oversized ones waste power on mild days.
What values do I need to enter?
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.