Space allowance is one of the most researched welfare variables in laying hen production. Science has clearly established the minimum space required for natural behaviour — and current regulatory standards in most countries fall far short.
Space allowance welfare science for laying hens is extensive and provides clear guidance that regulatory minimums in most countries are insufficient for welfare-positive housing. Hens in enriched cages at EU minimum space cannot simultaneously access all provided resources — some hens are permanently displaced from nests, perches, or feed during peak periods. Natural behaviour synchronisation — where hens perform simultaneous dust bathing or perching as a social activity — requires space that no cage system provides. Free-range and barn systems with sufficient indoor space and genuine outdoor range access allow a far greater repertoire of natural behaviour. However, indoor stocking density within free-range systems varies enormously — some operations house birds at 9/m² with active outdoor access while others maintain de facto indoor conditions. Welfare certification should specify indoor space alongside range provision. The strongest evidence supports a minimum of 1,500 cm² for welfare-positive individual space in any system.