A study on conditions of residential environment brought about by the local building code in Meiji Period

1) Aim of the Study Before the enforcement of the Urban Building Act in 1919, construction of buildings were under control of local police codes of Prefectures, Metropolitan Police Office and Hokkaido Administration Office. As an individual administration used to take an independent action in operating the codes, there was hardly a systematic relation between each other. In past years we collected as much data as possible to systematize the codes. In the process we learned that the environmental conditions brought about by operation of such codes have not yet been fully studied. Thus we decided to study the Local Building Control Code in the Meiji Period with a focus on the architectural aspect, specifically the Meiji Building Code, and tried to clarify what environmental conditions were expected with the Code. 2) Contents of the Study As a preliminary survey, we collected urban maps of the concerned districts at first and then as much literature and data as possible to learn how the urban districts looked like those days. We found out that both on plans and on sections, the districts of the Meiji Period appeared quite characteristic. In many of the districts there seemed to be much space between streets. Blocks were made up of alleys along which were built houses in rows that are called NAGAYA. In a main survey, codes of the Meiji Period were analyzed in detail. An analysis of rules for forms of buildings suggested us a model building with which we assumed various conditions; sky factors of the alleys and the duration of sunshine available for the model building can be calculated by preparing a sky diagram. The assumption tells us that in case of the 9-shaku (2.70 m) wide alleys with one-storey houses, reasonable standard of environmental conditions can be maintained.