We all want a greenhouse to warm things up. I’ve learned that you can have too much of a good thing, especially warmth in a greenhouse. The greenhouse effect is powerful and it can get roasting in an unvented space in short order. So after all of the effort to build a structure to make it warm we immediately figure out ways to cool it down!
My friend and capable helper Kay Burton is on hand to lend a hand figuring these things out. He built the vent closures on the upper vents and then devised ways to open and close them.