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Not sure what size exhaust fan you need for your greenhouse kit? Our greenhouse fan size calculator does all the work for you. Just enter in the greenhouse dimensions into the fan calculator below. We offer complete greenhouse exhaust fan systems with thermostats, or you can purchase exhaust fans and controls separately.
Greenhouse Fans Chart

This chart shows the typical # of degrees warmer the inside of the greenhouse will be versus the outside air temperature if the ventilation system is running constantly.

- Chart assumes the exhaust fan and intake(s) are installed in opposite end walls (as shown below without any other openings near the fan).

- Individual results may vary. Chart does not take into account factors that can affect results like greenhouse shape, covering type, and area's sun intensity.

Greenhouse Fan Size Calculator
Length of Greenhouse (feet)
Greenhouse Exhaust Fan
Width of Greenhouse (feet)
Peak Height of Greenhouse (feet)
W x L x H x 0.85
Fan CFM Needed - This is the minimum recommended exhaust fan CFM (Cubic Feet per Minute) rating for your greenhouse. A fan this size will exchange the air in your greenhouse at least once per minute which is recommended for venting small greenhouses.
Click here to view our selection of exhaust fans and systems.
Greenhouse Evaporative Cooler CFM Calculator
Cooler CFM needed with no shade cover on the greenhouse.
Cooler CFM needed with a 50% or higher shade cover.
Click here to view our selection of evaporative coolers.
Note: You need to have Javascript enabled on your browser for the calculators to work.


This chart provides you with the recommended intake shutter sizes for the exhaust fan sizes specified. Two shutters are recommended for greenhouses over 10 ft. wide to provide better distribution of fresh air.
Recommended Fan Intake Shutter Sizes
Exhaust Fan Size 1 Intake Shutter 2 Intake Shutters 4 Intake Shutters
12" Exhaust Fan 16" Intake 12" Intakes 8" Intakes
16" Exhaust Fan 20" Intake 16" Intakes 12" Intakes
20" Exhaust Fan 24" Intake 20" Intakes 14" Intakes
24" Exhaust Fan 30" Intake 24" Intakes 16" Intakes
This chart provides you with the recommended exhaust shutter sizes for the evaporative cooler models specified.
Recommended Cooler Exhaust Shutter Sizes
Evaporative Cooler Size 1 Exhaust Shutter 2 Exhaust Shutters 4 Exhaust Shutters
3500VK Cooler 20" Shutter 16" Shutters 12" Shutters
5800VK Cooler 30" Shutter 24" Shutters 16" Shutters
 Variable Speed Wired Exhaust Fan Systems fan, cooling, greenhouse, shop, exhaust, ventilation, package, garage, shutter, louvered, automatic, thermostat, 8005, 8005150, 8005155, 8005160, 8005165, 8005170, 8005175, 8005180, 8005185, 800567
Price: $425 - $865

Need help sizing a fan system for your greenhouse? Use our Exhaust Fan Size Calculator Each fan system is packaged with all of the equipment needed to provide an automated fan system for your greenhouse, shop, or garage. All included items are sized to provide optimal functionality of each fan ventilation system. Links are provided below to each piece of equipment in the fan packages. Just click on the text for more information. Dimensions and specifications are also provided in the...

Greenhouse Evaporative Air Cooler swamp, cooler, evaporative, evap, water, air, greenhouse, kit, cooling, cheap, room ,unit, fan, intake
Free Shipping
Price: $439 - $649

Screened Venting & Cooling all in one!Evaporative air coolers, also called pad or swamp coolers, have proven to be one of the most effective cooling systems for a greenhouse short of an air conditioner. It pumps water over the special cooling pads which lowers the temperature of air passing through them. A powerful fan pulls air through these pads and pushes the cooled air into the greenhouse. Hot air can be exhausted through roof vents or exhaust shutters and can be automated with one of our...

Basic Plug In Exhaust Fan Systems fan, cooling, greenhouse, shop, exhaust, ventilation, package, garage, plug, louvered, automatic, prewired, 8006, 8006100, 8006105, 8006110, 8006115, 8006120, 8006125, 8006130, 8006135, 800567
Price: $279 - $519

Need help sizing a fan system for your greenhouse? Use our Exhaust Fan Size Calculator No wiring required! This is the easiest fan system to setup available. Just plug the fan into the thermostat. Then plug the thermostat into an outlet, and you are ready to go. Each ventilation system is packaged with all of the equipment needed to provide an automated fan system for your greenhouse, shop, or garage. All included items are sized to provide optimal functionality of each fan system. Links are...

Premium Plug-In Exhaust Fan Systems fan, cooling, greenhouse, shop, exhaust, ventilation, package, garage, plug, louvered, automatic, prewired, 8007100, 8007105, 8007110, 8007115, 8007120, 8007125, 8007130, 8007135, 800567
Price: $429 - $799

Need help sizing a fan system for your greenhouse? Use our Exhaust Fan Size Calculator No wiring required! All equipment just plugs into the thermostat. Then plug the thermostat into an outlet, and you are done. Each fan system is packaged with all of the equipment needed to provide an automated fan and intake(s) for your greenhouse, shop, or garage. All included items are sized to provide optimal functionality of each fan ventilation system. Each fan system also comes with a waterproof...

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ACF Greenhouses
380 Greenhouse Drive
Buffalo Junction, Virginia 24529
1-888-888-9050 toll free

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