I recently erected a Riverstone Monticello Greenhouse. It is 8x12 ft (2.43x3.65 m), has dual doors at one end which open to a width of approximately 4 ft. (1.2 m) It has 2 roof vents - one on each side of the roof located at one roof panel in from each end. The roof panels are 2 ft wide (0.6 m) - so each vent is approximately 2 ft (0.6 m) from each end of the greenhouse.
I purchased a solar fan that specifies about 1350 cfm. (38 cubic meters/minute) I'm hoping this will be adequate for the greenhouse. Normally I would think the best mounting position would be at the non-door end in the gable. But because of the location of the roof vents, I am not sure.
I live in Southern United States (North Carolina) and I am seeing about 15-20 degree temperature differential in full sun with both roof vents and doors fully open. In the summers we can have many weeks of 100+ degree Fahrenheit temperature (38 degrees C)
So the question is where should I mount the fan? If I mount in the non-door gable should I close the roof vent on that end of the greenhouse? I leave the doors and both vents fully open during the daytime in the warm weather.
Thanks in advance for your comments. Just joined today and all this stuff is pretty new to me.
Small greenhouses tend to heat up quick and cool quick with the right ventilation! I line fands to push the air at the lowest point. The air pressure caused b the fan will push the upper air out the vents. I suggest 2 50 gallon drums of water below our tables or on the north wall of the greenhouse with the fans blowing against them. This will maintain a better temp both on cold night and hot days! One drum can be a source of water for your plants. you can even put a weak solution of miracle grow in the one drum to water plants!