The new buildings acoustic classification scheme in Spain: the standard UNE 74201

In September 2021, the document that develops an acoustic classification scheme was approved in Spain. It is the UNE 74201 standard that is described in this paper. The Spanish ACS is applicable to new and existing buildings for private or public residential use, for health/hospital and educational use. The development of this document has been a challenge which, requested by the construction sector, has been completed after 5 years of collaborative work, within the Technical Committee CTN74/SC2 - Building Acoustics of the Spanish Standardisation Body, UNE. It's been achieved an ACS compatible with the "DB HR" Spanish building acoustics regulations and, in turn, in agreement as much as possible with ISO/TS 19488:2021. The standard defines different levels of noise protection by using a system of six classes for the requirements, A to F, where Class D defines the minimum requirements for acoustic quality that are mandatory to fulfil in the building code. Criteria for airborne, impact and façade sound insulation, for service equipment noise and for reverberation time are included. This paper shows in detail the verification, sampling and class assignment procedures developed in the standard. A comparison of the most general aspects with other European schemes is also shown.