The effective use of floor space and the number of chickens in a barn system can be increased by adding separate slatted tiers. Aviary or multi-tier systems enable the production of cage-free, organic and free-range eggs. The platforms for jumping in each tier help the birds to move between different levels and perches stimulate them to perform natural behavior. Drinking and feeding systems are ready integrated in the tiers. Automated laying nests offer hens a peaceful and dark environment for laying eggs, which results in clean eggs.