The climate in hatcheries influences the health and grown of birds. Respiratory, digestive and behavioural disorders are more likely to occur in houses in which the climatic conditions are not controlled.

The younger the animals are, or the higher their production level, the more sensitive they become to the climatic conditions in the house, as temperature and relative humidity.

Too high relative humidity can lead to condensation in the house. Humidity control also decrease the chances of survival for micro-organisms, which can be harmful to the birds.

The relative humidity for hatcheries should ideally be maintained from 60 to 80%.