房间

Why does 房间 look like this?

房 (House) = 户 (Door/Household) + 方 (Square/Direction, also provides the sound 'fáng'). It represents a room within a house. 间 (Space/Between) = 门 (Gate) + 日 (Sun). Imagine the sun shining through the gap in a doorway; it signifies a space or room.