Rooms: The Main Building is a a tile-sliding puzzle game where the player character becomes trapped in a mysterious mansion with ever-changing rooms. A side-view of the mansion is used as the playing field for each level, while the tiles are represented as rooms which the player slides around to help create a path that allows the on-screen character reach to the exit.
The "tiles" are drawn from a pool of 100+ different rooms to create unique level layouts. Some rooms also contain objects which the player can use to manipulate tiles or have the character travel throughout the level to better solve the puzzle.
Meeting certain requirements while completing the puzzles for a mansion will unlock additional mansions, each with their own set of puzzles to solves. Rooms also features a competitive two-player mode where each player races to solve the puzzle and reach the exit first. Players can also use the Level Editor to create their own puzzles.