Well due to my location, it will be more of a shadehouse in the summer but we do get a "real" winter here so it will be a GH in the winter and I will have to plan for heat. I haven't gotten to that part yet as summer just started and we don't get cold weather until November...yay!
I'm thinking a polycarbonate roof and shade cloth for the sides during summer and removable polycarbonate panels for winter..kindof like removable storm windows. I'm thinking I will mount the polyc. in wood or aluminum frames and attach them when the weather turns.
As far as orchid types...I'm still developing which ones do the best for me so I have a lot of variety. So far, the Dens, Oncs, Epis, and Tolus are doing the best with a couple of Catt crosses (Slc, Blc etc) doing well. The others...well the jury is out. They are doing okay but I wouldn't say they are in the optimum environment.
The one thing I am unsure of is if screen door material would be too shady. I want to keep out the mosquitos. They get bad here. The shade cloth has bigger holes and the little pests will get inside and eat me alive.
I do have a line on some tempered glass from an OB member that might work out great if the dimensions are right, but it depends on his location and whether I can convince hubby on a road trip.