Start with the Coop Size Calculator to size your coop for your flock, then read the build basics below.
1. Size it right
Crowding is the #1 backyard mistake — it leads to feather-picking, fighting, and disease. Rough rules of thumb:
- Coop interior: ~4 sq ft per chicken (more if fully confined).
- Run: ~8–10 sq ft per chicken.
- Nest boxes: 1 per 3–4 hens.
- Roost: ~10 inches of bar per chicken.
2. Ventilate without drafts
Ammonia and damp are health killers. Add high vents near the roofline to let stale air out, while avoiding drafts at roost height.
3. Predator-proof — including underground
- Use hardware cloth, not chicken wire — raccoons can tear chicken wire apart.
- Bury the mesh or add an apron to stop foxes and dogs from digging in.
- Use two-step latches a raccoon can’t open.
4. Make it easy to clean
A lift-up nest-box lid, a pull-out droppings board, and an off-ground design turn daily cleaning from a chore into a two-minute job.
These are common backyard rules of thumb, not engineering specs; adjust for your climate, breed, and predator pressure.