A Parametric Tool for Assessing Optimal Location of Buildings According to Environmental Criteria

Site-climate design is the first phase to be carried out for a sustainable design of a building. In some local building codes and environmental rating tools, specific requirements related to building location on the plot are included. Generally, in site design, solar access and wind protection/exposition are the two most considered parameters, together with local temperature conditions. An effective tool to analyse the environmental quality for localising a specific function and activity on a plot is the “site microclimate matrix”. This technique, firstly developed in the US, includes solar and wind access analyses for specific days of the year and hours of the day (able to represent seasonal limits). Sunny and shaded areas in the plot are overlapped to areas protected and exposed to wind in order to classify the entire plot in four classes (sunny-calm, sunny-windy, shaded- calm, shaded-windy). These classes can help in applying a score of bioclimatic suitability for the location of several indoor/outdoor functions and activities. Solar access is generally determined by using instruments such as solar charts and shading mask protractors, while few science-based tools have been applied so far for assessing wind access and protection. For overtaking this gap, a method is presented here, including a parametric definition of wind wake core areas. The paper will introduce a parametric tool able to calculate, for parallelepiped solids, wind wake cores and shadow profiles to calculate a site microclimate matrix. This calculation can be performed not only on the plot plane but also in three dimensions. By using this matrix, it can be possible to classify the volume of the plot for a sample of activities and suggesting their more suitable localisation. Considering the algorithmic nature of the proposed tool, able to directly interact with a CAD- based environment, it will be possible to define indicators for assessing the optimal environmental quality of an urban design project.