The total environment of a broiler house — lighting, litter quality, air quality, water access, and stocking density — determines the welfare of the birds within it, with evidence-based standards increasingly specifying all of these variables.
Broiler house environment is not a single welfare variable but a system of interacting factors that each contribute to overall welfare. A house with good lighting, adequate litter, appropriate air quality, and accessible water provides a substantially better welfare environment than one that compromises on any of these. Evidence-based standards that specify all environmental variables create a welfare floor that prevents the worst outcomes, while high-welfare systems that exceed standards on multiple dimensions demonstrate what is achievable for commercial broiler welfare.