Yingzao Fashi is a technical treatise on architecture and craftsmanship written by Li Jie, an architect and official at the Directorate of Buildings and Construction.
Li had completed the book in 1100, and presented it to Emperor Zhezong of Song in the last year of his reign.
His successor, Emperor Huizong, has Li's treatise officially published three years later, in 1103, for the benefit of foremen, architects, and literate craftsmen.
The book is intended to provide standard regulations, not only to the engineering agencies of the central government, but also the many workshops and artisan families throughout China who can benefit from using a well-written government manual on building practices.
Yingzao Fashi includes building codes and regulations, accounting information, descriptions of construction materials, and classification of crafts.
In its thirty-four chapters, the book outlines units of measurement, and the construction of moats, fortifications, stonework, and woodwork.
For the latter, it includes specifications for making bracketing units with inclined arms and joints for columns and beams.
It also provides specifications for wood carving, drilling, sawing, bamboo work, tiling, wall building, and decoration.
The book contains recipes for decorative paints, glazes, and coatings, also listing proportions for mixing mortars used in masonry, brickwork, and manufacture of glazed tiles, illustrating practices and standards with drawings.
His book outlines structural carpentry in great detail, providing standard dimensional measurements for all components used; here he develops a standard eight-grade system for sizing timber elements, known as the cai-fen system of units, which can be universally applied in buildings.
About eight percent of Li Jie's book is derived from preexisting written material on architecture, while the majority of the book documents the inherited traditions of craftsmen and architects.
The Yingzao Fashi provides a full glossary of technical terms that include mathematical formulae, building proportions, and construction techniques, and discusses the implications of the local topography for construction at a particular site.
He also estimates the monetary costs of hiring laborers of different skill levels from various crafts on the basis of a day's work, in addition to the price of the materials they will need and according to the season in which they are to be employed.