Getting the coop size wrong is the most expensive beginner mistake with chickens - not because the coop costs more, but because a crowded flock starts pecking, and that is hard to undo.
| Area | Space per bird | Why |
|---|---|---|
| Inside the coop | 2-3 sq ft | Roosting and shelter; less than this and bullying starts |
| In the run | 8-10 sq ft | Exercise and foraging; confinement without space causes feather-pulling |
Bantams manage with about two-thirds of that. Large breeds - Orpingtons, Brahmas - need the upper end or more.
| Birds | Coop (inside) | Run | Nest boxes |
|---|---|---|---|
| 3 | 6-9 sq ft | 24-30 sq ft | 1 |
| 4 | 8-12 sq ft | 32-40 sq ft | 1-2 |
| 6 | 12-18 sq ft | 48-60 sq ft | 2 |
| 8 | 16-24 sq ft | 64-80 sq ft | 2-3 |
| 12 | 24-36 sq ft | 96-120 sq ft | 3-4 |
The run figures assume the birds are shut in. If they free-range for part of the day, the run can be smaller - but not the coop.
The instinct is to seal a coop against the cold. That is the wrong instinct. A sealed coop holds ammonia and moisture, and that causes respiratory disease far more often than cold does.
2-3 square feet per bird inside, plus 8-10 square feet per bird in the run.
About 12-18 square feet inside (roughly 3ft x 5ft) and a run of 50-60 square feet, plus nest boxes.
Two. One per 3-4 hens - though they will all use the same one anyway.
Yes, more than it needs insulation. Leave high vents open year-round to clear ammonia and moisture.
If you want the full beginner walkthrough - coop plans, breed selection and the first 8 weeks: The First-Time Chicken Keeper's Checklist.
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