Much in the traditional architecture of Japan is not native, but was imported from China and other Asian cultures over the centuries. Japanese traditional architecture and its history are as a consequence dominated by Chinese and Asian techniques and styles (present even in Ise Shrine, held to be the quintessence of Japanese architecture) on one side, and by Japanese original variations on those themes on the other.[2]
Partly due also to the variety of climates in Japan and the millennium encompassed between the first cultural import and the last, the result is extremely heterogeneous, but several practically universal features can nonetheless be found. First of all is the choice of materials, always wood in various forms (planks, straw, tree bark, paper, etc.) for almost all structures. Unlike both Western and some Chinese architecture, the use of stone is avoided except for certain specific uses, for example temple podia and pagoda foundations.
The general structure is almost always the same: posts and lintels support a large and gently curved roof, while the walls are paper-thin, often movable and in any case non-carrying. Arches and barrel roofs are completely absent. Gable and eave curves are gentler than in China and columnar entasis (convexity at the center) limited.[2]
The roof is the most visually impressive component, often constituting half the size of the whole edifice.[2] The slightly curved eaves extend far beyond the walls, covering verandas, and their weight must therefore be supported by complex bracket systems called tokyō, in the case of temples and shrines. Simpler solutions are adopted in domestic structures. The oversize eaves give the interior a characteristic dimness, which contributes to the building's atmosphere. The interior of the building normally consists of a single room at the center called moya, from which depart any other less important spaces.
Inner space divisions are fluid, and room size can be modified through the use of screens or movable paper walls. The large, single space offered by the main hall can therefore be divided according to the need.[2] To the contrary, some walls can be removed and different rooms joined temporarily to make space for some more guests. The separation between inside and outside is itself in some measure not absolute as entire walls can be removed, opening a residence or temple to visitors. Verandas appear to be part of the building to an outsider, but part of the external world to those in the building. Structures are therefore made to a certain extent part of their environment. Care is taken to blend the edifice into the surrounding natural environment.[2]
The use of construction modules keeps proportions between different parts of the edifice constant, preserving its overall harmony.[2] (On the subject of building proportions, see also the article ken).
Even in cases as that of Nikkō Tōshō-gū, where every available space is heavily decorated, ornamentation tends to follow, and therefore emphasize, rather than hide, basic structures.[2]
Being shared by both sacred and profane architecture, these features made it easy converting a lay building into a temple or vice versa. This happened for example at Hōryū-ji, where a noblewoman's mansion was transformed into a religious building.