You buy a greenhouse thinking it's going to keep your plants warmer. And it does, like 70° warmer.
I find the real challenge with a greenhouse or hoophouse is keeping it cool. I have removable ends, windows and screen doors on my hoophouses so I can open them up to let things cool off. But that's not enough. I also have 60% shade cloth and exhaust fans. That keeps them 90-100° most of the time during the hotter weather. For what it's worth, the ambient temperature where I live rarely gets above the low 90s .
Pro-tip: you can open all the vents and windows in your greenhouse and stick a box fan(s) in the doorway in a pinch. But its better to have dedicated fans.
Also, thermal mass works both ways, warmer at night and cooler during the day. I keep a row of cinder blocks in one of my hoophouses Nov-May
