Adattare gli standard. Un metodo parametrico per la correzione degli standard di superficie lorda nell’intervento sul costruito

The process of building system standardization allowed to define a system of clear rules to guide the design from scratch. Regarding space standards, they can be divided into two categories: those referring to gross floor area and those referring to minimum dimensions of spatial elements. Usually the first ones are used at the meta-design level for a preliminary calculation of spatial requirements, while the latter are used in definitive and executive design, to define rooms area. On the contrary, intervening on a historical building means entering into an already defined environmental system that has its own characteristics and constraints. Thus, in a conservative approach to built heritage, it’s necessary to adapt the new uses to the actual building. This involves sacrifices in terms of efficiency in space use, and it’s no longer possible to rely on predefined standards. In the absence of adequate tools to assess the compatibility between functions and existing spaces, the most common approach involves moving directly to architectural design. This implies a long and expensive evaluation whose outcome is uncertain. Only after having elaborated the whole project it is possible to check if a specific function is settable in a given building. The development of new tools to act on a meta-design level on historical buildings is an opportunity to evaluate the feasibility of intervention in a faster, more concise and less expensive way. To use space standards in historic buildings it is thus necessary to define suitable correction coefficients, taking into account the specific features of the existing building. Considering intended uses with high spatial modularity, the paper will present a procedure for defining correction coefficients. In particular we identified a series of significant factors to quantify the influence of the differences between the historical building and a newly built building for the same function.