Building a chicken coop takes time, at least some skills, and a lot of careful planning. Before you start hammering, pull out some graph paper and make sure you address everything a chicken needs to stay healthy and safe.
Coop size and shape. Each chicken needs at least 2 square feet of indoor space, or 3-6 square feet in an outdoor run. For example, for indoor chickens, you should multiply the number of chickens by 2 to get the minimum square footage.
Ventilation. Chicken coops need good ventilation, through windows, roof vents, exhaust fans, and/or other means. Usually, cool air enters near the floor, is warmed, then exits near the top. Taller coops will require both top and bottom ventilation points.
Roosts. These considerations protect your chickens from injury. Make sure to consider cleaning in your design. Options for keeping a clean roost area include a slide-out pan or door, a pit, or a flat board that can be removed and scraped.
Shelter. A coop must keep chickens warm and dry, and therefore healthy. Chickens must have access to a shelter and a windbreak (temporary, natural, or permanent) to protect from winter winds.
Sturdy floor. Sagging floors are uncomfortable for the chickens and look unsightly.
Protection from predators. Predators are a big problem for urban, suburban, and rural coops. At the very least, the chickens should have a predator-proof shelter at night, when they’re most vulnerable.
Temperature control. Chickens are most comfortable when temperatures range between 40 and 85 degrees Fahrenheit. Extremes — cold or hot — can be dire. Make sure to choose chickens that are well-suited to your climate, and take advantage of natural resources (shade, time of year). In hotter climates, provide higher ceilings, extra space, and good ventilation.
Lighting. Light — either natural or artificial — is necessary for chickens to eat, drink, and even lay eggs. An artificial light source makes evening chores possible, keeps hens more active in winter, and help defend from predators.
Clean surroundings. Good drainage in the outside areas prevents moisture (and odor) build-up. Many chicken-keepers install hard-surfaced floors that can be hosed (especially in hot, dry climates) or sand or gravel that keeps the birds’ feet clean. Avoid slippery flooring such as tile, paper, or metal, especially for meat birds.
Wire floors are sometimes used for meat birds for cleanliness, but they can cause breast sores in broiler-type birds. A deep litter should be used to cushion these birds, and it should be kept clean and dry.
