How much room?

7 hens x 4 sq. feet each = 28 sq. feet needed from housing. Some sources say you can get by with less, but if there's a chance they'll be confined at times, I'd stick with the general rule of thumb (4 ft. for standard chickens). That could be a 4 x 7 coop, a 5 x 6 coop (a little extra room is always good). Because most 2x4s and such come in 8 ft. sections, maybe a 4 x 8 coop??? Then you could make it an even 8, or just have more room for your seven... The run is another matter...about 10 ft. per hen unless they are free ranging...

 

I always tend to go overboard re size of my animal pens but, I have 8 chickens in a 5 x 12 coop and I would absolutely not want it any smaller. They do have a large attached run but they spend a fair amount of time in their coop when the weather is bad or when it's too hot out. (mine is constructed of hardware cloth and built into one end of my goat barn, so it's very open and airy in there.) But I would make it as large as you reasonably can. They'll be more comfortable and less apt to pick at each other.