What is a Chinese roof truss?

Chinese roof truss is an important part of Chinese residence. It consists of wooden components such as rafters, purlins and rafters. The roof truss is located at the roof ridge, and the purlins on both sides are separated. The rafters were laid across the purlin and covered with tiles. Most roof trusses in China are 5-purlin or 7-purlin structures, and some 9-purlin structures are rare. Multi-purlin structure generally has a main purlin and a secondary purlin, and the secondary purlin is also called two purlins, which is parallel to the main purlin. The main roof and the secondary roof are supported by melon columns, and the roof truss lacking the secondary roof is also called wax gourd column. The lower part of the main roof of China roof truss is generally supported by columns, which are divided into front eaves and back eaves.