Thanks everyone for your replies.
Yes Astroron you have waited quite a while for me to get motivated and put this up.
Joe, the frame around the doors is to stop them from twisting when they are opened.
Shawn, the doors seal very well from letting in rain and can be closed from inside if an unsuspected shower comes. Also when open they stop the wind from buffeting into the open observatory. Try and design observatory so that the telescope is back atleast 2 feet (even more) from the opening to minimise wind buffeting.
