A covered litter box has certainly the advantage that there is less cleanup since the litter can’t spill over the side after an energetic digger covers her waste.
You also might think that a covered box makes it more private and tranquil for a cat to relieve herself. But a few cats feel trapped in a vulnerable situation, worse still are the litter boxes with a flapping door.
For a larger cat, the walls of a covered litter box reduce the amount of space she has to turn and squat without pushing up against the sides of the box or the top.
For the people not seeing the litter itself, it is too easy to forget to scoop it frequently enough.
Because there is no air circulation, the stench and fumes of the urine and faeces stay trapped inside. Just imagine what it’s like for the poor kitty, with a much more sensitive sense of smell, to use this toilet!
There are cats which will prefer covered boxes, because they are timid and scared and look to relieve themselves in hiding.
If you get a covered box and your kitty is not happy, you always can take off the top and at least have a litter box with high walls and therefore less spillage.
For an average cat: the sides of the box can be about 6 inches (15 cm) high, low enough to pop over easily, but high enough to contain the litter when the cat covers up after herself.
As convenient it may sound, self-
For kittens: the box should be large with low sides so it is easy for the little kitty to get up and over.
For seniors: the box should be large with low sides, because arthritis can make it difficult or painful to step over a side of any height.
For an energetic litter scratcher: taller sides will keep more of the litter inside.
Length: the box should be twice as long as the cat herself – at an absolute minimum 1.5 times.
Width: the box should be one cat-