Move and refresh the stagnant air in your greenhouse or building to create a healthier and more productive developing environment. These greenhouse exhaust fans are excellent for reducing plant and worker heat stress. Our exhaust supporters provide superb ventilation for high tunnels and cool frames. Create 
a cooler more comfortable growing environment, that may directly contribute to efficiency, quality and profitability for your greenhouse business. Exhaust fans also functions great in workshops and buildings.
Move and refresh the stagnant air in your greenhouse to create a healthier and more productive environment. These exhaust & circulating fans are great for plant growth. Create a cooler convenient growing environment, which can directly contribute to productivity, quality and profitability for your greenhouse business.
The concept of cooling a greenhouse with thermal buoyancy and wind goes back to the beginning of managed environment. All greenhouses built just before the 1950’s had some type of vents or louvers that were opened to allow the excess heat to flee and cooler outside surroundings to enter.
When polyethylene was developed with large sheets covering the whole roof, placing vents on the roof proved difficult. Engineers then came up with the idea of using fans that pull outside atmosphere through louvers in one endwall and exhaust it out the opposite end. With thermostatic control, this is, and still is the accepted way for cooling many structures where positive air movement is needed.
Growers with hoophouses have found that roll-up sides work very well for warm period ventilation. Both manual and motorized systems can be found. A spot with good summer breezes and plenty of space between houses is needed. It can help to have greenhouses made with a vertical sidewall up to the elevation of the attachment rail to lessen the quantity of rain that can drip in.
Greenhouses with roof and sidewall vents operate on the principle that temperature is removed by a Greenhouse Exhaust Fan pressure difference created by wind and temperature gradients. Wind performs the major function. In a well designed greenhouse, a wind quickness of 2-3 miles/hour provides 80% or more of the ventilation. Wind moving over the roof creates vacuum pressure and sucks the heated surroundings out the vent. If sidewall vents are open up, cool replacement atmosphere enters and drops to the floor level. If the sidewall vents are closed, great air enters underneath of the roof vent and the heated are escapes out the very best of the vent.