That depends on your climate, is the shed in the sun, and how you can use windows, screens, fans, dehumidifiers, and space heaters. I do it in a semi finished second floor of a barn. No AC, tbh there are days that it is needed, but I manage without. The power bill is bad enough with the grow and the AC in the house. Start with a digital hi/low recording thermometer/hygrometer and get some data to decide.