I appears difficult nowadays to get anything built in budget and on time, doesn't it? It will be interesting to see how much "solar-heat" advantage we gain in the winter months. We are using state-of-the-art glass that reflects most the infra-red and practically all of the UV spectrums. It is also supposed to have a super-high insulation factor, so during the winter months, little heat is suppose to escape and little cold is supposed to enter. During the warm months, the cool is supposed to stay inside and the heat outside. Time will tell what those stated factors really mean. Everything looks good on paper!
Just to be safe, we are installing a dedicated AC/heat unit in this room, a 1 1/2 ton unit that is rated for 1500 sf. of floor area, and installing two ceiling fans in the "porch" ceiling, a fan design that is supposed to move twice the air as an ordinary ceiling fan.