Determination of passive acoustic requirements of buildings
All new buildings must comply on site with the sound insulation limits set by D.P.C.M. 5/12/1997 “Determination of passive acoustic requirements of buildings” (in force since 20.02.1998).
Despite over the years there being several regulation vicissitudes that led to discussions about its applicability, currently the D.P.C.M. 5/12/1997 is in force and must be applied to all newly constructed buildings.
Although the decree does not specify anything in regard, by virtue of various interpretations by authoritative organs of the State, it is recommended to apply the D.P.C.M. 5/12/1997 in the event of renovations and change of use destination.
In particular, the limits imposed by the regulations are:
1. Insulation of walls and fl oors against airborne noise;
2. Impact sound insulation;
3. Insulation of the facade against airborne noise from outside the building;
4. Insulation of discontinuous operating systems (elevators, plumbing drains, bathrooms, services, toilets, taps);
5. Insulation of continuous operating systems (heating, ventilation and conditioning);
6. Limitation of the reverberation time of classrooms and gyms.
TABLE A - Classification of living environments
|CATEGORY A||Buildings used as residence or similar purposes|
|CATEGORY B||Buildings used as offices and similar purposes|
|CATEGORY C||Buildings used as hotels, pensions and similar activities|
|CATEGORY D||Buildings used as hospitals, clinics, nursing homes and similar purposes|
|CATEGORY E||Buildings used for school activities at all levels and similar purposes|
|CATEGORY F||Buildings used for recreational or worship activities|
|CATEGORY G||Buildings used for commercial activities or similar purposes|
TABLE B - Passive acoustic requirements
CATEGORIES REFERRED TO TABLE A
* R’w values refer to the separation element between two separate housing units.
As it regards the limitation of the reverberation time within school buildings, the D.P.C.M. 15/12/1997 dictates that “The average reverberation times measured at 250-500-1000-2000 Hz frequencies, shall not exceed 1,2 sec. in a furnished classroom, with the presence of two people at most. In gyms the average of the reverberation times (if not to be used such as an auditorium) must not exceed 2,2 sec “.
In case of failure to comply with the limits set by the D.P.C.M. 15/12/1997, the responsibility will fall on the following subjects:
1. The Designer, the Director of Works and their advisors: for the choice of materials and construction systems and for monitoring their correct installation.
2. The builder: for correct installation of materials and construction systems.
3. The Municipality: for the failure to check the documentation demonstrating compliance in place of passive acoustic requirements.
4. The Client: in case of sale of the property to a third party not regulated.
It is important to stress that the D.P.C.M. 15/12/1997 requires compliance ON SITE of the passive acoustic requirements: the performance of laboratory certificates or reports of calculation is not nearly enough to certify compliance with the regulatory limits.
Therefore for the purpose of verifying whether the building complies or less than what had been expected from D.P.C.M. 15/12/1997, after its completion, you should always conduct sound level tests, which will be edited by acoustic consultants, writing in the applicable provincial or regional list (as provided by Law No. 447/1995). Sometimes, it is preferable to perform sound measurements even during construction, to make any constructional modifications in case you encounter any exceedances of the regulatory limits.
D.M. OCTOBER 11, 2017 - Minimum environmental criteria for the awarding of design and construction services for the new construction, renovation and maintenance of public buildings.
The most recent and most revolutionary regulatory novelty of recent years is represented by the entry into force of the Ministerial Decree on Minimum Environmental Criteria (CAM).
The decree deals with the new construction, renovation and maintenance of public buildings, in particular schools, nursing homes and hospitals, but also swimming pools, gyms and sports halls. For these works, unlike what happened previously, the designer must prepare a report that demonstrates compliance with very restrictive limits, both for soundproofing (walls, floors and systems) and for sound absorption. The new Decree, in point 22.214.171.124 (Acoustic Comfort), clearly specifies how the acoustic descriptors required by the UNI 11367 standard (shown in the following pages) should be used, with regard to the passive acoustic requirements of the real estate units.
Furthermore, the D.M. October 11, 2017 establishes that, for internal environments intended for the word, the descriptors reported by the UNI 11532 standard must be used, with particular reference at least to reverberation time and to the STI (Speech Transmission Index). It is expected that the professionals in charge must provide evidence of compliance with the rules, both in the planning and forecasting phases, delivering respectively an acoustic project and a test report showing the results of the phonometric tests performed in situ.