You're gonna need a fan in that building. Lack of a fan is what keeps my green house from being truly functional. It gets up to 110 when the sun shines on it, even when the doors at each end are wide open. That's one of my "in the future" projects. I'd actually like to make a stick built green house off the west end of my house. I've been collecting storm window and patio doors for that project. My plan is a building about 10 x 12 (or larger... what ever I can talk hubby into! Built on skids, Framing for glass windows on S and W walls, Solid walls on N and E, Polycarbon roof. Heat sink floor, Possibly an aquaponic system as well as standard soil beds.