Do you have somewhere, such as a storage room where you'd wish to keep a litter box, but you can't be sure the door will always be open?! Well, the Cat Door is your solution!
We built one for our cat to be able to get to our basement where we keep his litter box so we don't have to keep the door to our basement open at all times. They can be useful for other pets, like dogs, If you want them to be able to get into other parts of your house, where a door may be blocking the way.
They're typically easiest to build during construction your houses or when your remodeling/finishing parts of your house, but can be built in a completed house.