I lived in San Marcos for a while when I went to school. I'm in Magnolia near Houston. I bought a coop kit from Tractor supply and have put up a 16 x 24 ft yard around it. I'm In the process of roofing an 8 x 16 end section to build in an 8 x 8 coop. The birds have out grown the kit coop. I am surprised at how big they are at 11 weeks. I thought they would take six months to get big since they don't lay til then. SURPRISE! I lived here when I was a girl and my father came in from north Louisiana to help me build my chicken house for FFA. It was done in a weekend and my Dad paid a fellow to install the yard later. That chicken house was successful. These days there are so many small coops that have runs in the bottom like rabbit cages which inspired me to place the windows at the floor level on the west and south instead of at the mid to ceiling level. I thought the North side should be solid to guard against wind and the upper south end solid as well with a platform under the roost. The boxes on the north, door on the east, vents or windows at the upper west and east for ventilation. I scrapped the Purina Mills idea of a sun roof, expecting too much Gulf Coast Texas heat in the summer and possibly Spring, Fall and part of the Winter. I planned to have a cat walk on the west side with a chicken board and the house is a split level open design. Here's my concern. Considering how hot it gets here and our mild winters, do you see any problem with the lower level indoor run area compromising the warmth or creating too much wind or weather exposure? The idea is to double the floor space and to allow for delays in yard time for the chickens, so that if I am un able to open the door in the morning or in poor weather, they still have ground to scratch, a view, and space to run around. I am basically securing the yard and the coop and allowing for a run within the coop that is loft style without closing off the roost and opposing nesting boxes at the center of the coop. Do you think the vents at the top will be enough to prevent excessive heat at the roost?