Urban noise and required facade acoustic insulation of buildings: the case of some agglomerations in Italy

The paper presents the results of a study on the relationship between environmental noise and façades sound insulation requirements to ensure acoustic comfort in indoor environments. In particular, it analyzes the relationship between outdoor noise determined according to the European Noise Directive and limit values necessary for the acoustic classes of buildings. The relationship is proposed as a contribution to the new Italian legislation on acoustics that is going to be adopted and in general to other countries’ legislations. A short description of the buildings acoustic classes proposed by the COST Action TU 0901 that is going to be im-plemented as new ISO standard is included. Building exposure to noise is described through the indicator Lden as reported in the noise maps of the Italian agglomerations. The relationship between façade acoustic classes and outdoor noise level is studied taking into account the proposal of COST Action TU 0901 and is applied to some important cities in northern, cen-tral and southern Italy (Turin, Milan, Bologna, Florence and Bari), estimating the number of buildings exposed to every noise level band.