I am new to register but a long time reader of BYC and I am also in Florida. I was given 3 adult guineas by an elderly man and before I knew it chicken math had kicked in and I got 2 silky chickens. I am now looking to get a "few" laying hens. I can't have roosters, yet!
I will be starting on my coop this weekend. I found a chain link dog kennel on CL, 6' tall, 20' long, 5' wide that is expandable. It has 2 gate panels and a solid dividing panel. I found a coop on the design page that has super good instructions, can be modified to suit our heat, and can be modified for expansion. The design is for an 8' x 4', which is probably what I am going to start off with but the solid back wall can be removed and expanded if need be. I think that is very likely with my chicken math.
The front top of the coop design is wire, which I will keep. The side walls will also be wire with the ability to insert solid slide ins if needed. The roof will be wire with a sloped roof above it leaving room for hopefully good ventilation. I am on 5 acres of woods and have found a spot that stays shaded most of the day and although it is a bit further from the house then I would like, it will be the best spot for the chickens.
I want to thank everybody on here for their wonderful tips, designs, and insights and to let everybody know that your help is far reaching even to folks who are not members of BYC. I am so grateful to have found all the information on ventilation. Without it, my chickens would have suffered in the Florida heat. So, thank you all.