Abstract: A cat relief chamber includes a front, a back, a floor, a first side, a second side, and a roof. The front has a doorway formed therein to allow for a cat to enter and exit the chamber. The chamber is adapted to be sold as a substantially flat preform and then expanded by a consumer to a formed state. The floor of the preform is assembled such that the floor forms as the consumer expands the preform to form the chamber. The doorway is formed from a door panel in the front of the chamber. The door panel is pushed in along perforations. The door extends upwardly from the bottom of the chamber, and when pushed in, becomes a part of the floor of the chamber. The chamber can be formed easily and quickly by the consumer and without the use of glue.