The ancient buildings in eastern Zhejiang are mainly made of wood and bricks and tiles, and the main structural method is wooden frame structure. This structural method is built with main components such as columns, beams, and purlins. The joints between the components are matched with mortise and tenon joints to form a flexible frame. There are three different structural methods of ancient wooden frames: lifting beams, through beams, and well-beams. The lifting beam type is to place beams on the columns, and then lift beams on the beams, so it is called "lifting beam type". This structural method is often used in large buildings such as palaces, altars, temples, and temples. The through-beam type is to connect rows of columns with through beams to form a frame, and then connect them with beams and purlins, so it is called through-beam type. It is mostly used in residential houses and smaller buildings. The well-beam type is made of wood stacked crosswise, and is named because the space it encloses resembles a well. This structure is relatively primitive and simple, and is rarely used now except in a few forest areas. The wooden frame structure has many advantages. First, the load-bearing and enclosure structures have clear division of labor. The weight of the roof is borne by the wooden frame, the outer wall plays the role of blocking sunlight, heat insulation and cold protection, and the inner wall plays the role of dividing the indoor space. Since the wall does not bear weight, this structure gives the building great flexibility. Secondly, it is conducive to earthquake prevention and earthquake resistance. The wooden frame structure is very similar to today's frame structure. Due to the characteristics of wood, and the brackets and mortise and tenon joints used in the structure of the frame have some room for expansion and contraction, so within a certain limit, the damage caused by earthquakes to this structure can be reduced. "The wall falls but the house does not collapse" vividly expresses the characteristics of this structure. The ancient buildings have beautiful shapes, especially the roof shapes, which are mainly in the form of Wudian, Xieshan, Xuanshan, Hardshan, Cuanjian, and Curved Sheds. Whether it is Wudian neck or Xieshan roof, they are all large roofs, which appear stable and coordinated. The straight lines and curves in the roof are cleverly combined to form a slightly upward eaves, which not only expands the lighting surface and is conducive to the drainage of rainwater, but also adds to the beauty of the building's flying and briskness. Information source: Ningbo Cultural Center (Ningbo Exhibition Hall Ningbo Intangible Cultural Heritage Protection Center) Information source: Ningbo Cultural Center (Ningbo Exhibition Hall Ningbo Intangible Cultural Heritage Protection Center)