My new coop is going to be 12ft by 12ft and Ive looked everywhere to try and find these answers, but came up with nothing. Is there a 'rule of thumb' when placing windows, doors, vents, etc. on the chicken coop? For instance..should I put my windows only on the East facing wall? Or putting the vents on the South side wall? Would putting a door into the coop on the lower left hand corner be okay? See picture below, its how part of my backyard is setup and where the new coop and run will be.

Also what is a good place to put together a mock up of this online? Isnt there something on google or yahoo someone was talking about one time? For making plans and blueprints. Cause I also want to see what the best way to setup the inside of the coop would be as well. Right now I have 6 adult chickens, 12 five(?) week old chicks, with 2 or 3 more coming. So I will have a total of 20 or 21 chickens. I know its plenty of room, but I also want to add a place to store the feed and also maybe have a place for a brooder.
Anyone have any good ideas or advice?

Also what is a good place to put together a mock up of this online? Isnt there something on google or yahoo someone was talking about one time? For making plans and blueprints. Cause I also want to see what the best way to setup the inside of the coop would be as well. Right now I have 6 adult chickens, 12 five(?) week old chicks, with 2 or 3 more coming. So I will have a total of 20 or 21 chickens. I know its plenty of room, but I also want to add a place to store the feed and also maybe have a place for a brooder.
Anyone have any good ideas or advice?