Greenhouse Ventilation Systems
Proper ventilation is one of the most important parts of designing a successful greenhouse. The hot summer sun can quickly overheat a greenhouse if proper ventilation is not provided. At the very least, a good greenhouse requires vents near the highest point because heat rises and should be allowed to escape in the summer. Shutter vents and exhaust fans installed in the peak on gable ends of the greenhouse work very well.
We carry only the highest quality aluminum and PVC fans and shutters. These are not the flimsy, thin fans and shutters found with most greenhouse kits. Our shutters have a strong extruded aluminum or PVC frame and our fans are designed for professional greenhouse installations.
Determine the proper size ventilation system for your greenhouse by calculating the cubic feet of air space in the growing area and plan to replenish that once a minute for optimum cooling in summer.
Length x Width x Wall Height = Recommended CFM (Cubic Feet per Minute)
Circulating Fans
Plants will grow healthier and stronger with the proper amount of air circulation. Your greenhouse should not be drafty, but air movement should be slightly noticeable to prevent hot spots or cold spots. Good air circulation is valuable in both summer and winter and also helps prevent disease.
Exhaust Fans
Powered exhaust fans are recommended for any greenhouse that is larger than 8 x 12 or has direct sun exposure from the south or west. Use the simple CFM calculation above to determine the proper size ventilation system for your greenhouse.
Intake Shutters
Intake shutters enable fresh air intake at the same time the exhaust fan pulls air out of your greenhouse. These high quality shutters are hinged and balanced with such precision that the suction power of the exhaust fan on the opposite end of the greenhouse will pull the shutters open when the fan is running. The shutters then automatically close when the fan shuts off.
Solar Powered Vent Openers
These automatic vents are activated by the heat of the sun. During the day, the sun warms up a paraffin wax inside the black cylinder and expands a piston that opens the cantilevered vent. As the sun goes down and the greenhouse cools, the piston retracts and the vent closes. These are surprisingly reliable and temperature adjustable.
