"Letters from Home" clearly points out that "three rooms are auspicious, four rooms are few, and five rooms are empty". The meaning of this sentence is that Yang is considered as Yang in odd numbers, and many yin houses are used in even numbers, and three represents many meanings. Generally speaking, as the old saying goes, three rooms decide the outcome, so three is a lucky number. Four rooms are rare. If only four rooms are built in a house, it will be rare, just like the meaning of coffin house, which will lead to the death of teenagers in vain. One of the five rooms is empty, which is decided by Luo Shu, and there are five rooms in the four directions and five elements. When it meets five, one room will be designated as the prison room in the middle palace, so one room should be empty.
Because of these geomantic sayings, there is a saying that the floor pays instead of buying a pair. Another saying refers to all rooms in the house, including bedroom, kitchen, bathroom, bathroom, study, storage room and so on. This means that when buying a house, it is lucky to add rooms such as bedrooms and bathrooms according to odd numbers, but unlucky to add them according to even numbers.