How to Install a Ventilation System in a Greenhouse

Flow-Through Ventilation System

• 1

  Design your greenhouse with windows on the ridges that can open and close. The ridge is the slanted roof. Place windows toward the top of the ridge and on both sides of the ridge. Space them no more than every 3 feet.

• 2

  Use automatic solar ventilation window openers for best performance. To install, ensure that the window opens and closes easily. According to manufacturer's instructions, clamp the opener onto the metal frame of your greenhouse centered under the window. (If the frame is wooden, attach a clamp with a screw.) Clamp the opening tip of the opener to the bottom of the window. Check how far open you can push the window with the opener attached. If you can open the window at least 16.5 inches, follow the manufacturer's instructions to set the opener. Heat and light will cause it to open to ventilate the greenhouse for you.

• 3

  Consider placing vents in the sides of your greenhouse every few feet. Do this on both sides. Vents will remain closed in calm weather and allow air in during windy weather. Purchase vents that are the same length and width as the glass or plexiglass pane, and install the vent instead of the pane. During times that you wish to prevent wind from entering the vents, cover the vents with greenhouse plastic sheeting. Tape the sheeting on the outside frame of the greenhouse with an industrial-strength tape.

• 4

  Purchase solar-powered fans and set them inside of the window or vent openings. You may also place them in an open doorway. Run the cord outside the window or vent, and rest the solar panel on the ridge of the greenhouse.

Forced-Air Ventilation System

• 5

  Place a large, industrial-size fan in the back door of the greenhouse. For smaller greenhouses with no back opening, place the fan in the front doorway.

• 6

  Run an industrial-strength, outdoor power cord from your power source out to your greenhouse.

• 7

  Attach the greenhouse fan to the cord. Open the windows in the greenhouse. Check the temperature and humidity in the greenhouse periodically throughout the day.

• 8

  Place solar-powered fans in the windows of the greenhouse. Run the cord out the window and rest the solar panel on the ridge. (This step is optional when there is an industrial greenhouse fan running.)