Best for
Hot climates, larger structures, or greenhouses where passive vent area is constrained.
#6 in the buying orderVentilationSystem component
Bootstrap Farmer Greenhouse Exhaust Fan
An exhaust fan is the powered step after passive roof and side ventilation cannot hold the target temperature.
- Current price
- $159.99 to $903.99
- Checked September 1, 2026
- Review type
- Independent desk review
- Not a physical product test
Skip if
You have not sized the airflow or provided a matching intake path. A fan pulling against a sealed greenhouse does not deliver its rated flow.
Hidden cost
The intake shutter, thermostat or controller, weather-safe electrical work, framing, and operating power are separate lines.
Why it made the list
The buyer case
The 12, 24, and 36-inch range provides a coherent system path, and the fans are prewired for 115V with a grounded cord.
Compatibility comes first
Size by greenhouse volume, heat load, intake area, and the actual electrical circuit. Pair it with a low intake on the opposite end.
Installation boundary
Mount high on the hot end of the greenhouse with intake low on the opposite end. Electrical and structural work should follow local requirements and the product manual.
Our verdict
A credible powered ventilation component, but not a one-box solution. Buy the complete air path, not just the fan.
Primary sources
Product facts come from these direct sources. They are kept separate from the purchase button, and none is rewritten through an affiliate redirect.
Keep comparing
Related accessories
#2Buy firstVentilation
Canopia Automatic Greenhouse Vent Opener
Check a current US distributor
A heat-activated opener is the accessory that protects plants when the sun comes out and nobody is home.
- Best for
- Canopia owners with a compatible roof vent who want passive opening without power or a controller.
- Skip if
- Your vent is not a compatible Canopia roof vent, the frame binds, or the site is exposed to strong winds that require the vent to stay locked.
#5Buy when neededVentilation
Bootstrap Farmer 12-Inch HAF Circulation Fan
$159.99
A circulation fan moves stagnant air inside the greenhouse. It does not exhaust hot air outside.
- Best for
- Greenhouses with condensation, dead corners, or uneven temperatures after the basic venting path is already correct.
- Skip if
- Your actual problem is removing heat from the structure. A circulation fan cannot replace roof vents or an exhaust system.
#7System componentVentilation
Bootstrap Farmer Aluminum Intake Shutter
$68.99 to $501.99
This is the missing half of many exhaust-fan purchases: a controlled path for replacement air to enter.
- Best for
- Powered exhaust systems that need a passive low intake matched to the fan size.
- Skip if
- You do not have a powered exhaust fan or have not calculated the intake area. It is not a general wall vent recommendation.