The impact of 60% +2 code on Tehran's common row house construction

It has been said that the legislation of rules and regulations, has been affected the form, construction and the relationship between different forms of life in residential buildings. In the city of Tehran, the occupancy code along with the regulation of construction exactly in the northern 60 present of plot with the feasibility of projection for 2 meters, considering beveled corners (45 degree), was one of the codes legislated for the common row type houses. It seems that this code had a lot of effect on Tehran’s residential areas which created a type of housing called row houses. In this type we can distinguish two different species called the northern houses and the southern one. There are obvious differences between these two types that know to be as a reason of the regulation specially the construction portion and its beveled corners. Howbeit the beveled corners are not obligatory any more but we can see its effect on city image. Row type houses along with its northern and southern species with the high of three to six stories is defined as the common residential building patterns of Tehran’s houses. Because of this dominance in Tehran as a capital and then in all Iranian cities, it is very important to address this issue as a research topic. So in this research we are going to investigate around the effect of these kinds of regulation and codes on residential buildings. The question arises here is that to what extent this code can influence Tehran’s housing. The main question of this research is to realize the effect of the 60 percent occupancy of the plot with a possibility of 2 meters projection on residential areas in three scales including residential unit’s itself, its surroundings and other residential buildings and its neighborhood to have a comprehensive study. For the three above mentioned scales, three type of characteristics covering the quality of architecture mentioned by capon, has been selected which consist of performance-behavior, structure and building physics and perception-space. Then these characteristics have been evaluated in available Tehran’s samples of row houses. The characteristics and the scales shape a matrix which forms the theoretical Framework of this research. So this frame work used to evaluate the effect of this code. Therefore each of the 9 portions of the framework matrix filled by three instances of effects. With a help of logical reasoning as a research method of this paper, the effects of 60 percent plus 2 meters projection code, has been evaluated through this framework. All the 27 effects which have been founded, consist of day lighting factors, view and landscape, overlook through the triangular balcony created because of the beveled corners, etc. categorised in three main groups of overlook, the quality of day lighting and spatial proportions. These three factors can seriously affect the quality of living in each residential units or apartments which has been increased by solely a code called 60 percent plus 2 meters.