Redefinition of Building Placement Regulations towards Conservation of Historical Urban Fabrics: A Case Study of Lahijan

The current research is an attempt to reconsider one of the key regulations in the contemporary building control system pertaining to the historical fabrics of old cities in the southern coasts of the Caspian sea. It specifically concentrates on building placement and plot coverage regulations. These two interwoven regulations perform as a mediator between urban design and architectural design disciplines. The research emphasizes that these regulations should be based on vernacular building placement patterns. In this paper first a report is provided of the negative effects of the current building placement and plot coverage regulations. After that it is attempted to identify the principal characteristics of a desirable approach to the subject based on an analysis of a number of relevant international experiments. Next, as a case study the paper continues to examine historical urban fabric of Lahijan city, an old city in Guilan province. An examination of the aerial photos of the city from 1956 on, and extensive field visits indicate that in the vernacular architecture of Lahijan there were two main types of building placement patterns. First and the most common pattern was the perimiter placement of the residential building/buildings in a plot of land. It could take 15 different forms. The second pattern was a pavilion-like placement pattern which could take five different forms of arrangement. In order to investigate the frequency of each pattern, in the aerial photo of the city of 1956 the whole city is divided into 50 square pieces among which 10 pieces are selected and examined. In each piece the number of houses that uses any one of those placement patterns, is calculated. In sum 286 houses are examined and the most popular patterns are identified. These vernacular patterns can be used as a basis to rewrite the relevant regulations.