Cooling my greenhouse

My husband and I built a 10x12 gabled greenhouse this past fall and early winter and built it out of wood with a clear corrugated poly carbonate. Now that were in the beginning of summer we are finding it difficult to cool. We have venting, a white sheet on the south side of ceiling, we have the west Gable screened to allow release of heat, and we have a continual fan, but it’s getting up to 110°f during the warmest part of the day. What can we do to cost effectively cool it?

Look into aluminet reflective shade cloth which will bring temps down at least ten degrees. No other shade cloth has worked as well for me. You don't say where you are but shade cloth goes on here after May 1st regardless of nightime temps. Is your fan a gable vent fan with thermostat? How many doors do you have? Are they screened? If you are located in a very hot place consider a small swamp cooler. I am seeing portable room air-conditioning units that you add water to. They must be versions of swamp coolers and may be perfect for your small space. Meanwhile, the most important thing to address is proper shade cloth.

Hi, we are in Zone 8b. We are putting up a 10'x15' prefabricated, tempered glass greenhouse. It will have 2 automatic vents on top, 2 louvered windows on the sides, and two hinged doors. Given our zone, I think it will be pretty easy to keep the greenhouse warm with a heater on our few cooler days, but I am concerned with keeping the greenhouse cool in the summer. We do have pretty solid tree canopy on the south and west sides of the greenhouse, so I'm hoping that will provide some dappled shade. We plan to use the greenhouse not only for growing veggies, but as a place to relax on cooler days, so we want to make it pleasant to sit in. The greenhouse will have a concrete slab floor (slightly sloped to the center for drainage) covered with brick or some sort of decorative tile. Is there a certain type of tile that we can install on top of the slab to help keep the greenhouse cooler? Would a light tile work best? I was wondering if, conversely, brick or a dark slate might actually absorb the heat out of the air during the day and keep the rest of the greenhouse cooler, and then release the heat at night...but that may be magical thinking. Thermodynamics is not my area... Any suggestions would be greatly appreciated!!!

This message was edited Nov 17, 2021 10:03 AM

This message was edited Nov 17, 2021 10:08 AM

How tall is the roof at the peak? You will need a serious greenhouse fan as well as roof shading to make it bearable in Austin's summers. Otherwise, you might consider a window unit air conditioner. A greenhouse fan is noisy and might make it less than ideal to hang out. See the reference to Aluminet above for shading. Otherwise you can use a greenhouse white wash coating that wears off gradually.

Your floor should be light or you will create a heat sink. I used Tennessee fieldstone in the small solarium off of my family room. I can clean it with a carpet shampoo machine. Though indoors, the solarium skylight and shade can be operated electronically. The room is heated and cooled but can be dampered and closed off from the main house. The greenhouse is completely separate and attached on one wall to that room.