Official ruling by the High Council of Public Works (Consiglio Superiore dei Lavori Pubblici): The D.P.C.M. of 5 December 1997, in defining its scope of application as “buildings and their on-site components”, did not specify that the regulations introduced apply only to new constructions. Consequently, in the Section’s opinion, the relevant provisions — and in particular the compliance with and fulfilment of passive acoustic requirements — must also be applied to the renovation of existing buildings involving even the partial reconstruction of technical systems and/or of horizontal or vertical partitions (floor slabs, roofing, partition walls, etc.) and/or of the external building envelope (excluding mere painting of façades), or the subdivision of property units within the building — that is, ultimately, all renovation interventions affecting the parts of the building subject to the passive acoustic requirements regulated by the D.P.C.M. of 5 December 1997, as can be inferred from the decree itself.

Achieving the values required by law is neither difficult nor particularly expensive when addressed during the construction phase, whereas it becomes more complex and costly — and sometimes technically impossible — once the work is completed. During the design phase, by applying the appropriate construction techniques, it is possible to select low-thickness or low-cost materials, generating substantial savings on the overall cost of the project. Upon completion of the construction work, the Works Director certifies the building’s fitness for occupancy, also declaring compliance with health and safety requirements, including the parameters identified in Table B, Annex A of D.P.C.M. 05/12/1997; to this end, a report is attached, prepared and signed by a technician competent in environmental acoustics, who may draw on the results of instrumental measurements carried out on site.