Welcome to BYC. Glad you decided to join our flock. X2 on the dimensions that drumstick diva gave you and those are the bare minimum (more is definitely better). Also, definitely use hardware cloth, not chicken wire, as there are too many predators that can either tear through chicken wire, or squeeze through the openings in the mesh. Please feel free to ask any questions you may have. We are here to help in any way we can. Good luck in building your coop.