Better urban microclimate via a proposed city planning tool. A case study in Greece

Abstract

In Greece, the minimum mandatory distance (D) of a building from the plot’s boundaries, relates only to the building’s maximum height (H), given as D = 3 + 0.10*H. This is the main institutional tool that shapes urban open spaces and, consequently, the urban microclimate in Greece. In this paper, we will illustrate a numerical model for city planning, named D (b) in an attempt to define mandatory minimum distance between building structures on different plots, taking into account the ground relief and climatic conditions of an area. The methodology we used to create the model is based on bibliographical sources for bioclimatic design. In particular, we were interested in identifying data regarding the sun’s height angle (V sun), the height of the building causing shading (Z building), the desired shadow height (Z shadow), and the ground slope (ω). Our model was a pilot one applied in the city planning of a sparsely built area (a separate unit) to be incorporated in the master plan of Serres town in Northern Greece. Two city planning scenarios were developed (one using the presently applied, and the other using the proposed tool), and the results of the expected thermal islet, as given by the two scenarios, were evaluated in comparison. The results of this pilot program suggest that bioclimatic distance between building structures [D (b)] contributes to the utilization of passive energy saving systems. Thus, it could be institutionally utilized and, in combination with currently observed distances, could constitute a valuable addition to the existing city planning tools in Greece.