Correlation between facade sound insulation and urban noise: a contribution to the acoustic classification of existing buildings

The aim of this work is the definition of a methodology to analyze the number of buildings exposed to every noise level band, to estimate the required facade sound insulation for indoor comfort, and to evaluate the acoustic classes that would characterize existing building facades adopting the proposal for a new International Organization for Standardization standard. In particular, a relationship based on a statistical approach is analyzed between outdoor noise, determined according to the European Noise Directive, and the limit values for the acoustic classification of buildings that are going to be implemented in the proposed International Organization for Standardization standard. Building exposure to noise is described through the indicator Lden as reported in the noise maps elaborated, according to the European Noise Directive, with reference to some major Italian towns. As a result of the application of the proposed methodology, the facade insulation required to obtain an adequate indoor comfort is determined.