1. The auspicious numbers of the door openings on the Luban ruler:
If converted to metric sizes, the usual auspicious numbers are 21-23cm, 40-42cm, 60-62cm, 81cm, 88cm , 89cm, 106-108cm, 126-128cm, 133cm, 146cm, 155cm, 171-176cm, 191-198cm, 211--216cm, 231-236cm, 241cm, 253-256cm, 261-263cm, 275cm, 281-283cm.
2. Generally speaking, the height of modern doors does not exceed 283cm. For ordinary residences, the width of the door (that is, the visibility, which is the horizontal distance of the inner wall of the door frame, excluding the thickness of the door frame) is mostly 108cm. , the height is mostly about 212cm, while the width of the door is mostly 81cm, and the height is mostly 198cm. This size is suitable for everyone.
Extended information
1. Luban ruler is also called "menguang ruler": Luban ruler is a widely popular construction tool among ancient Chinese people. Generally used to measure and size residential doorways and furniture. In "Luban Jing" and "Luban Construction Official", it is called "Luban Zhenchi" and "Luban Zhouchi". In ancient times, people believed that a door determined by the auspicious size of the Luban ruler would shine in the courtyard and bring good luck to the family, so the Luban ruler was also called the "Gate Light Ruler".
2. Because each foot of Luban ruler is divided into eight inches, and terms expressing various meanings are written on each inch, the people also call Luban ruler "eight-character ruler", "door ruler" and "door ruler". Meter" etc.
3. Ancient Kanyuology attached great importance to the use of Luban ruler. The "Ten Books on Yangzhai", a work on Kanyuology, says: "There are several kinds of door rulers in the country, and they have been tested many times, but this ruler (Luban ruler) is the real one. The length and the short are in harmony, and there is no difference between good and bad. It was built by Gongshu Ziban in the past, and it is made of extremely wood. Zhi Shengyan, because of the insignificant nature of creation, created this ruler, and later generations called it Luban ruler. It can be used for all bed and room utensils."
Reference material - Baidu Encyclopedia. -Luban Ruler