Floor space first: how a Pekin house is measured
An adult Pekin duck needs roughly 4 square feet of floor space inside the duck house per bird and 8 to 10 square feet per bird in a secure outdoor run, with additional ranging space beyond that whenever it can be offered safely. A Pekin is a big, fast-grown meat breed kept as a pet, weighing far more than a laying duck, and that weight is carried on relatively delicate legs and feet. Every figure in a Pekin's housing plan should therefore be read generously: a house that merely fits the flock on paper will be damp, soiled and stressful in practice.
Unlike chickens, Pekins do not roost, so vertical space and perches are wasted on them. What they need instead is unbroken, dry floor they can settle onto at night, with deep absorbent bedding that cushions their breast and feet. Doorways should be wide and step-free or served by a gentle ramp, because a heavy Pekin forced to hop up a high threshold will eventually injure a leg doing it.
Water changes the space calculation for ducks
No duck space plan survives contact with water unchanged. An adult Pekin needs drinking water deep enough to submerge its whole head, and given any bathing water at all, it will splash a wide radius of ground into mud. Site the drinkers and any splash tub on the run's best-drained corner, ideally over gravel or a washable slab, and keep that wet zone as far from the sleeping house as the layout allows. Inside the house, water should generally not live overnight at all; a Pekin flock shut in with an open bucket will soak the bedding by morning.
Swimming water is enrichment, not a requirement, but if you offer a pool or pond the ranging area needs a gently sloped entry a heavy duck can waddle down, not a steep bank. Allow space around the water for the whole flock to gather without smaller or lower-ranking birds being trapped against a fence by their flockmates.
Field and run considerations for a heavy white duck
On range, an adult Pekin is an enthusiastic but slow forager, vulnerable in a way ranging chickens are not: it cannot fly, runs poorly and is conspicuous. Field space for Pekins therefore has to be secure space, fenced against dogs and foxes and covered or supervised where birds of prey hunt, and the secure run is where the flock should spend any unsupervised hours. Shade is essential across the run and field, because a white, heavily built duck overheats quickly on a still, sunny afternoon and will choose shade over forage every time.
Grass under a Pekin flock wears differently from grass under chickens. Ducks dabble and drill into wet soil, so low corners of the field will be excavated into muddy hollows unless you rotate the ranging area or rest those patches. Moving fencing periodically spreads that damage and gives the ground time to recover.
Watch-outs that trace back to space and ground
The classic Pekin problems are leg and foot problems, and most trace back to surfaces and crowding. A duck limping, sitting down frequently on short walks, or developing sores on the underside of the foot needs the ground, bedding depth and house space reviewed, and a veterinarian's advice if the bird is not bearing weight normally or a foot looks swollen and hot. Overcrowded, wet housing also drives respiratory trouble in ducks, so a house that smells strongly of ammonia at duck height is telling you the flock needs more space, more bedding turnover, or both.
Writing down the house dimensions, the water setup and which part of the field the flock is using helps every member of the household keep the routine steady, and KinsLe Family Sharing keeps those Pekin housing details shared so nothing depends on one person's memory.