The rooms are underground.

The floor is 5 plates thick and 72 studs square (Nine 8x8 plates each direction).

Doors can be placed at the centre of either of the walls (North, East, South and/or West).

The doors are dark brown and are 6 studs wide and 6 bricks tall.  There should be 1 brick white border around the doors and tiles directly above the door with 'NORTH' 'EAST' 'SOUTH' 'WEST' labels in 1x1 tiles to indicate the direction.

The walls are 31 bricks tall.  The top layer of brick should be black to represent the earth below the ground surface. - So there are 30 brick layers of useable wall.  The walls are normally 1 brick thick (As are the doors).