What are the specific rules of the Qing official brick wall practice?

Generally, if the inner partition wall, fan-shaped wall and outer sill wall are made of brick, a splayed column door should be made at the intersection with the column, so the two sides of the column should be thickened according to a quarter of the column diameter, so the wall thickness is one and a half column diameters. As for the eave gable, when it is built with bricks, it is twice as thick as the inner wall, reaching three column diameters. The inside and columns are still zigzag, and the outside completely blocks the columns. However, in order to reduce the rot degree of the column root, a vent hole should be left on the outer brick wall at the lower part of each column, which is called "ventilation".

From the cross section of the wall, the upper two-thirds of the brick wall is thinner than the lower one-third, and the lower one-third has a special term called skirt shoulder, which is the same thickness from top to bottom. Two-thirds of the upper part is called the upper body, and there are obvious points on the outside, which gives people a sense of stability. The epidermis on the eaves wall is mostly connected with the epidermis under the eaves. Because the wall is thicker than the eaves, the top of the wall inclines inward, forming a slope shape, which is called the wall shoulder. Between the upper body and the shoulder, a brick board, waist line stone and other stones are used as the boundary between the two parts. In palaces and temples, the outer skin of the upper body is often decorated with red and gray, while the shoulders of skirts are often ground brick-to-seam, in sharp contrast with the white striped stone in the middle.

If it is a hard gable roof, its gable extends from the abutment to the top of the mountain, and the front and rear walls are roughly flush with the edge of the abutment. The upper part of the gable outside the eaves column is a stile, and there are suspended stones under the stile. This prominent stone is called "head and leg". The roof consists of a brick and a square brick, and the bricks are laid on the hanging stones layer by layer. First, there is a layer of lotus leaf pier on the second floor for owls, and then there is a line brick on the second floor, called pan head. There are eaves bricks on the head of the pan, which are placed vertically with the square bricks, so that the brick surface is slightly downward, and various figures and flowers are engraved on the brick surface. The eaves of the eaves tiles are flat.

In the case of suspended roof, if the gable epithelium is shaped like a beam and a melon column, there is a wall shoulder on each roof that is obliquely retracted under each beam, which is called Wuhua Gable.

The above mainly describes the provisions of the Qing official brick wall.