Because we have cats, dogs, ducks, geese, chickens and guinea pigs in the family, we use and build quite an array of small animal cages. There are a few critical points to consider when choosing housing for your pet or farm animal to have them be safe and comfortable.
1. Have enough space. A too-small cage is not good for your animal. Your pet will not get enough exercise if it has to stay in a small cage much of it's life. A small cage is okay if the cage is used only as a roost or as a sleeping or eating room for your animal. We have customers who use a small cage for their rabbits. The rabbits run free in the yard most of the time and only go up the carpeted ramp into their cage for food or to sleep.
2. Somewhat related to number one is having enough height to the cage. For taller animals such as chickens and ducks, the cage height should be about one and a half times the standing height of the animal. This is partly for comfort it is not be good for the animal not to be able to stand completely upright but is partially for air flow. Every cage should have good ventilation.
3. A comfortable floor. All our cages are made with 1/2 inch by 1/2 inch hardware cloth on the sides and the floor. The smaller wire can be a little more difficult to clean but provides a surface that is much easier on small animal feet. A piece of linoleum can be cut to fit the bottom of the cage or just a part of the cage for even more comfort.
With these the floorspace, height and correct flooring taken care of, your chicken, duck, hamster or whatever can be pretty comfortable. The only other things to add are food, water and appropriate bedding. We also like cages to be on legs to get the cages up off the ground, provide more ventilation and to make cage cleaning easier.