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Coop & run size calculator

Everyone quotes the same figure regardless of bird. A Brahma needs roughly double a Pekin bantam, and a flock that never leaves the run needs far more than one let out every evening.

6 standard chickens need

Sussex, Rhode Island Red, Wyandotte, hybrids. Most garden hens.

Coop floor

1.68

18.1 sq ft · about 1.3m × 1.3m

Floor area inside the henhouse, excluding nest boxes.

Run — recommended

9.6

minimum 4.8 m² · about 3.1m × 3.1m

The most common arrangement, and a good compromise.

Perch space
150 cm
25 cm each · no higher than 75 cm
Wide and flat beats round dowel — birds rest flat-footed and cover their toes in cold weather.
Nest boxes
2
33 × 33 cm each
One box per four hens. Site them lower than the perches, or they will roost in them.
Feeder & pop hole
72 cm
pop hole 30 × 35 cm
Split feeders and drinkers across at least two stations so one bird cannot guard everything.
  • Ventilation matters more than insulation: aim for openings above head height totalling roughly a tenth of the floor area. Chickens cope with cold far better than damp, so never seal a coop up for winter.
  • Manufacturers are optimistic. A coop advertised for eight birds is usually comfortable for four — measure the actual floor rather than trusting the label.
  • In Great Britain all bird keepers must register with APHA, including a couple of hens kept as pets. It is free, and it is how you get told about avian influenza nearby.

More on getting set up in before you get free range chickens, and on what it all costs in what backyard chickens actually cost.