Instructions for using the most accurate Lo Ban ruler

February 5, 2025

1. What is a Ban ruler?

The Lo Ban ruler is a type of ruler used for measuring in construction (Duong Trach - house, Am Trach - grave). On the Lo Ban ruler, there are common geographical dimensions and additional arcs to help determine good and bad distances that bring fortune or bad luck.

( The name Lu Ban according to recorded documents is a good carpenter of the Lu state who lived during the Spring and Autumn period, his name is Ban Ho is Cong Thau, Lu Ban can be understood as Mr. Ban from the Lu state).

2. Classification of Lo Ban ruler

- 52.2 cm Lo Ban Ruler (Clear space) : used to measure clear space such as doors , windows, floor height, skylights,...

The length of this ruler is 520 mm, divided into 8 large sections in order: Nobleman, Disaster, Natural Disaster, Human Fortune, Loneliness, Thief, Prime Minister.

- 42.9 cm Lo Ban Ruler (Solid Ruler) : used to measure solid kitchen countertops, measure the size of furniture such as tables, chairs, wardrobes, etc.

- 38.8 cm or 39 cm Lu Ban ruler (Yin part ruler) : used to measure altars, graves, etc.

2.1. 52.2 cm Lu Ban Ruler:

52.2cm Lo Ban ruler is also known as the clear-clear Lo Ban ruler . As its name suggests, the 52.2cm Lo Ban ruler is used to measure empty spaces in the house such as the clear space of the main door, side door, windows, vents, space between floors , etc.

52.2cm ruler

This void size is located in the limited living space, so it directly affects people.

Each Lo Ban ruler has a length of 520mm and is divided into 8 large sections: Nobleman - Danger - Natural disaster - Genius - Fortune - Loneliness - Thief - Prime Minister

52.2cm Ban Thuoc used to measure the clearance of doors and windows

Each large arc is 65mm long, the large arcs are divided into 5 small arcs, each small arc is 13mm long.

The Nobleman Palace means prosperous business, good family background, loyal friends. Filial and intelligent children. The way to calculate the Nobleman Palace is: nx L + (0.15 to 0.065).
The Hazard Palace means drifting away from home, family fortune and wealth are lost. Life falls into poverty, children are disloyal, family members often get sick, etc. How to calculate the Hazard Palace: nx L + (0.07 to 0.13).
The Thien Tai Palace according to the Lu Ban ruler means that you will easily encounter illness, death, and disease. You will lose money, your marriage will be in discord, your daughter will easily encounter accidents, etc. How to calculate the Thien Tai Palace: nx L + (0.135 to 0.195).
The Palace of Genius means good fortune, filial children, and a happy family. Parents are healthy, live long, and gain benefits from talent. How to calculate the Palace of Genius: nx L + (0.20 to 0.26).
The Phuc Loc Palace means that the homeowner will have many blessings, prosperity, and a developing career. The children will be intelligent, studious, and talented, and the family will be happy and peaceful. How to calculate the Phuc Loc Palace: nx L + (0.265 to 0.325).
The Lonely Palace shows that the family will experience separation, loss of wealth, property, and people. Children will be disobedient, indulge in excessive drinking and sex, and die. How to calculate the Lonely Palace: nx L + (0.33 to 0.39).
Thien Tac Palace means that the family is prone to sudden illness and misfortune. Prison, lawsuits, death, etc. How to calculate Thien Tac Palace nx L + (0.395 to 0.455).
The Prime Minister's Palace represents the meaning of a prosperous family in all aspects, with unexpected luck. Children will be wealthy, have a successful career, and have a noble son. How to calculate the Prime Minister's Palace nx L + (0.46 to 0.52).

Note:

n = 0; 1; 2; 3; 4; 5; 6; 7; 8; 9; 10; …
L = 0.52 meters
In the 52.2cm Lu Ban ruler, the good palaces will be the Nobleman - Genius - Fortune - Prime Minister palaces.

The commonly used rulers are 42.9 cm and 38.8 cm.

2.2. 42.9cm Lu Ban Ruler.

42.9cm Lu Ban Ruler is also known as Duong Trach Lu Ban Ruler and is used in construction blocks (kitchen, pedestal, steps...).

42.9cm ruler

The standard length of the feng shui ruler is 429mm and is divided into 8 different large sections in the order of Wealth, Illness, Separation, Justice, Official, Disaster, Harm, and Life.

Each large arc is 53.625mm long and each large arc is divided into 4 different small arcs, each small arc is 13.4mm long. In which:

The Palace of Wealth means talent and virtue, treasure, blessings and all 6 directions are good. How to calculate the Palace of Wealth: nx L + (0.010 to 0.053).
The Illness Palace means losing money, being lonely, being sent to the authorities, and facing imprisonment. How to calculate the Illness Palace: nx L + (0.055 to 0.107).
Ly palace means separation: loss, treasurer (having to mortgage belongings), Quan Quy (poor job), Kiep Tai (wealth and wealth). How to calculate Ly palace: nx L + (0.110 to 0.160).
The Nghia Palace means achieving good things and justice. The good meanings are adding people, giving birth to a noble son, encountering many good things, and benefiting. How to calculate the Nghia Palace: nx L + (0.162 to 0.214).
Quan Palace includes: career advancement, great wealth, increased benefits, and wealth. How to calculate Quan Palace: nx L + (0.216 to 0.268).
The Kiep Palace is prone to accidents such as death, leaving one's homeland, losing people, and losing money. How to calculate the Kiep Palace: nx L + (0.270 to 0.321)..
The Harm Palace means encountering bad things such as accidents, death, quarrels, and illness. How to calculate the Harm Palace: nx L + (0.323 to 0.375).
The Palace of the Original Meaning is the root consisting of the elements of wealth, prosperity, passing exams, and receiving gifts. How to calculate the Palace of the Original: nx L + (0.377 to 0.429).

Note:

The 4 good directions of the 42.9 ruler are Wealth - Justice - Official - Self.
When measuring dimensions, people use two types of rulers: A ruler with each arc length of 53.625mm is used to measure houses. A Lo Ban ruler with each arc length of 48.75mm is used to measure furniture.
n = 1; 2; 3; 4; 5; 6; 7; 8; 9; 10…
L = 0.429 m

2.3. 38.8cm Lu Ban Ruler.

38.8cm Lu Ban ruler, also known as Lu Ban Am Phan ruler, is used to measure furniture and tombs.

38.8m ruler

The standard length of this ruler is 390mm and is divided into 10 large sections in the order of Dinh, Hai, Vuong, Kho, Nghia, Quan, Tu, Hung, That, Tai. Of which there are 6 good sections and 4 bad sections.

Each large arc is 39mm long, each large arc is divided into 4 small arcs, each small arc is 9.75mm long. In which:

Dinh Palace (son) includes lucky star (lucky star), passing exams (coaching), wealth (money coming), passing exams (successful exams).
The Palace of Harm includes sudden disaster, verbal disaster, death, and illness.
The Palace of Prosperity includes joy, money, heavenly virtue, and abundant blessings.
The Palace of Suffering includes loss (loss of property), robbery (being robbed of property), disputes, lawsuits, and having no children.
The Palace of Justice includes Dai Cat (good), Loi Loi (beneficial), Thien Kho (heavenly treasure), Tai Vuong (lots of money). How to calculate the Palace
The Quan Palace includes wealth, fortune, passing exams, and advancement.
The Palace of Children includes: Ly Huong (far from home), death (someone dies), Loss of money, and Loss of son.
The Hung Palace includes passing exams, good children, prosperity, and having more children.
Palace Seven includes loneliness, public affairs, loss of money, and imprisonment.
The Palace of Wealth includes Nghinh Phuc (blessings come), Luc Hop (6 good directions), Tien Bao, Tai Duc (having money and virtue).