How Big a Coop Do 3 Chickens Need?
3 standard-size chickens need a 12 sq ft coop, a 30 sq ft run, 30 inches of roost, and 1 nesting box.
Figures reviewed against university extension guidance · Last reviewed July 2026
| Bird type | Coop | Run | Roost | Nest boxes |
|---|---|---|---|---|
| Standard breeds | 12 sq ft | 30 sq ft | 30 in | 1 |
| Bantams | 6 sq ft | 24 sq ft | 24 in | 1 |
| Heavy breeds | 18 sq ft | 30 sq ft | 36 in | 1 |
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 3 standard chickens, a 4 × 3 ft coop covers the12 sq ft floor requirement. Floor space means usable floor — don't count feeder footprints or the area under nest boxes mounted lower than 18 inches. The 30 sq ft run works out to roughly a3 × 10 ft enclosure attached to the coop.
Inside, plan 30 inches of roost — 1 four-foot roost bar mounted higher than the nest boxes — and 1 twelve-inch nesting box 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.
Other flock sizes
Sources
- Virginia Cooperative Extension — Small-Scale Poultry Housing (pub. 2902-1092)
- Colorado State University Extension — Brooding and Space Requirements for Poultry (2.502)