How Big a Coop Do 20 Chickens Need?
20 standard-size chickens need a 80 sq ft coop, a 200 sq ft run, 200 inches of roost, and 5 nesting boxes.
| Bird type | Coop | Run | Roost | Nest boxes |
|---|---|---|---|---|
| Standard breeds | 80 sq ft | 200 sq ft | 200 in | 5 |
| Bantams | 40 sq ft | 160 sq ft | 160 in | 5 |
| Heavy breeds | 100 sq ft | 200 sq ft | 240 in | 5 |
Rates: 4 sq ft coop and 10 sq ft run per standard bird (Virginia Cooperative Extension; Colorado State University Extension). Run figures assume birds are confined; free-range flocks need only the coop numbers.
What that looks like in practice
For 20 standard chickens, a 6 × 14 ft coop covers the80 sq ft floor requirement with 4 sq ft to spare. Floor space means usable floor — don't count feeder footprints or the area under nest boxes mounted lower than 18 inches. The 200 sq ft run works out to roughly a20 × 10 ft enclosure attached to the coop.
Inside, plan 200 inches of roost — 5 four-foot roost bars mounted higher than the nest boxes — and 5 twelve-inch nesting boxes in the darkest corner. These are extension-guidance minimums for healthy birds, not luxury targets: cold climates, bossy roosters, and pecking-prone breeds all appreciate more room.
Keeping different birds, or planning to free-range? Use the full Coop Size Calculator to adjust for bantams, heavy breeds, and run type.