Why not a shade sail with a gauzy fabric that would be rolled up most of the time but could be unrolled and tied down when you will be out? In my experience, the problem with temporary gazebos is that they fall apart in the wind. You would have a secondary issue that the shade sail is not engineered to hold the weight of the screen plus the wind the screen walls catch, so it would have to be a light fabric whatever you use (and again, I would suggest something you can roll up). I am going to be adding some cheesecloth-like fabric (not sure what I will use yet, maybe even old lace curtains, thinking "shabby chic") to my victorian kitchen porch so we can sit on it-it will add shade and bug protection. But I will do it so that I can roll it up into the roof if the wind is bad. We had one of those $300 gazebos (I think it was 10x10 or 12x12 when we lived in Illinois and it barely lasted the season before the wind sheared it. I think it was aluminum. Also, have you looked into solar fan options?

pozj, I have a 15x15 screened in porch that I hope to finish up this summer. Below is a link to a photo of the ceiling and soffit. I used 3/4" TG Fir on both. The intent is to have a nice contrast in color once I get the IPE sealed. http://wedman.smugmug.com/gallery/2116403#123006690 Ken

My builder used caulking and it has held up well. My gap wasn't very big as the structure was attached to the stud and the siding cut out (so it was tucked in kinda?)

Yes, the porch walk in door there is 80” tall and the overhead garage doors are 96” tall. I have read too about the egress windows and that is definitely what I want to stay with, just trying to figure out how to get the roof lines tied together and still save the window height.