dozō-zukuri 土蔵造

Keywords
Architecture
Storehouses

Also referred to as *kura-zukuri 蔵造. A fireproof building construction system that employed a timber structural frame and thick mud walls finished with plaster. Used principally as storehouses of the *dozō 土蔵 type. The system was also used for a variety of other building types and parts of urban houses, *machiya 町家, including the firebreak walls erected along urban plot boundaries. Shops constructed using dozō-zukuri were called *misegura 店蔵. A form of dozō-zukuri already existed in the Kyoto district by the late Kamakura period, but since no examples have survived, the structural details of this early phase are obscure. The technique had spread to all parts of the country by the mid-Edo period, but it was most extensively used and highly developed during the 19th century, when the greatest concentration of dozō-zukuri structures were built in the city of Edo and its cultural hinterland, the Kantō 関東 region. The chief structural features of dozō-zukuri in its mature phase may be summarized as follows: several courses of dressed stone, fuseki 布石, were laid upon carefully prepared foundations. Sill beams, *dodai 土台, were placed on these stones and the posts were tenoned into them at approximately 90 cm intervals. Penetrating ties, tōshinuki 通し貫, provided lateral stability. The posts, which were visible internally, had notches, tsutakakekizami ツタ掛け刻み, cut on their external faces approximately every 7.5 cm to receive horizontal bamboo canes, yokodake 横竹. Horizontal bamboo members called shakuhachidake 尺八竹 penetrated the posts at slightly wider intervals. These horizontal members were tied to vertical bamboo canes, tatedake 縦竹, with straw twine, nawa 縄, and the resulting interwoven mesh formed the framework upon which the plastered wall was built up. The precise techniques of execution varied, but in high quality work up to 16 layers of mud daub (incorporating varying proportions of chopped straw and straw rope) alternated with stiffened coats of wet sand, sunazuri 砂摺り (used to improve adhesion between layers), which were added in stages without any additional framework. The principal mud daub layers in order of application were called: arauchi 荒打ち (the coarse base coat plugged into the structural frame); tarumaki 樽巻き (actually several layers interleaved with sunazuri, incorporating vertical, diagonal, horizontal, and again diagonal lengths of straw rope to prevent the surface from cracking as it dried); *ōnaoshi 大直; konaoshi 小直; muranaoshi むら直; *nakanuri 中塗り; and *uwanuri 上塗り. They were added over a period of up to 4 years before the final coat of smooth fine white or black plaster, shikkuikabe 漆喰壁, was applied. Black plaster was known as Edo black, *edoguro 江戸黒, and was especially popular for buildings fronting the street in the Kantō region from the 19th century. Drying-out periods of from 2 to 6 months were included in the construction process at certain stages. The aim was to bury the inflammable timber structure beneath a protective epiderm 20-30 cm thick. Because great skill was required to ensure that each successive coat bonded properly to the one beneath, a master plasterer, sakan 左官, rather than a master carpenter, was often the senior craftsman on dozō-zukuri projects. Particularly in examples from eastern Japan, the daub and plaster wall was thickened near the base to define a dado and a loincloth. The plastering was also carried up to seal the area under the eaves, most often with a beveled cornice-like projection called *hachimaki 鉢巻 (headban). Roof tiles were embedded into a thick layer of mud or, if tile was not used, the daub and plaster was continued to the ridge beneath a weatherproof covering. Fully developed dozō-zukuri was an expensive and a time-consuming building technique, but the frequency of devastating fires especially in densely crowded urban areas, made the outlay a prudent investment. The terms *nuriya-zukuri 塗屋造 and *ōkabe-zukuri 大壁造 are sometimes alternative terms for dozō-zukuri, but they usually denote walling techniques, which were similar in principal but less substantial.