Room is the basic place for the most of the machines in the Assembly line world. You have 1 room from the start and you can build more later. Rooms can be placed on the ground or atop of the other rooms. Such machines as Money making machine, Coin stomper, etc, must be placed on the room's floor (or on the Cellar's floor).
Once placed the Room (any any other construction element) can't be moved, but it can be sold if there's no machines inside and no other construction elements, which this room supports.Sell button is activated on the press-and-hold event.
Building a room expands your visible zone upwards and (if the room is close to the screen edge) sideways