How hot will the GH get on a sunny, cold day?
Say it's 30 degrees outside, but sunny. Is there a way to calculate how hot a 4mm double wall polycarbonate greenhouse would get if it was kept closed all day (and was situated within 10 degrees of south)? In lieu of a calculator for this, any personal experience?
Right now, if it's 60 & sunny outside and I close the greenhouse for just a couple of hours, it hits well over 100.