There are 2 kinds of fans needed for climate control in the greenhouse.
These fans use little electricity. For only a few pennies a day, you can
create a healthy greenhouse environment.
1. Air Circulation:
is important to have a fan to circulate air through the foliage of plants,
24 hours a day, every day that you have plants inside your greenhouse.
This brings a fresh supply of needed carbon dioxide to the leaves. Air
circulation also prevents diseases that like to start in areas of cold
and stagnant air. This will also help with condensation inside your greenhouse;
the better the air circulation the less condensation as well as reducing
or eliminating hot and cold areas in your greenhouse. It is best to angle
the fan up or down to help break up any heat stratification that has taken
2. Heat Destratification:
Because warm air rises, a small fan is needed to pull
warm air off the ceiling and push it down to the plants on the benches
and floor. This is very important in the winter months, and helps reduce
What Size Circulation Fan Do I Need?
1. Greenhouse area x 10 = fan cfm.
- Example: 8' x 12' = 96 sq. ft. x 10 = 960 cfm.
2. If your greenhouse if half full of plants, deduct 50%
(960 x .5 = 480 cfm).
3. If your greenhouse is very full of plants, add 50%
(960 x 1.5 = 1440 cfm).
See our Air Circulation Solutions.