Legislation
Framework Law No. 447/1995 defines the fundamental princi-
ples for the protection of external and residential environments
from noise pollution, and considers four types of noise: air-
borne, façade, foot traffic and systems. Therefore, in designing
an underfloor radiant system, it is of fundamental importance
to consider materials that allow compliance with the foot traffic
noise levels established by the DPCM (Decree of the President
of the Council of Ministers) of 5 December 1997, whose limits
are listed below.
Forecast calculation of the index of attenuation of the sound
pressure level of foot traffic
The use of floating floors with foot traffic sound pressure abate-
ment properties is defined by the UNI EN 12354-2:2002 stand-
ard. This standard establishes that the use of a panel with
acoustic characteristics varies its foot traffic abatement power
based on the mass that is placed above the panel itself.
Below is an extract of the standard that shows the variation of
acoustic performance based on the surface mass placed above
the panel.
“Index of attenuation of the sound pressure level of foot
traffic, ∆Lw, of floating floors" .
The evaluation index of the attenuation of the sound pressure
level of foot traffic, ∆Lw, depends on the mass per unit area, m',
of the floating floor and the dynamic stiffness per unit area, s’, of
the resilient layer, as per EN 29052-1"Acoustics - Determination
of dynamics stiffness - Materials used under floating floors in
dwellings", measured without any pre-load.
Category A
Category B
Category C
Category D
Category E
Category F
Category G
residential buildings and similar
office buildings and similar
buildings used as hotels, guest houses and similar businesses
hospitals, outpatient clinics, nursing homes and similar
schools of all levels and similar
recreational or religious buildings and similar
commercial buildings and similar
•
For floating floors of concrete sand or calcium sulphate,
the values can be deducted from Figure C.1 of UNI
EN12354-2:2002, shown below.
CLASSIFICATION OF RESIDENTIAL ENVIRONMENTS
and PASSIVE ACOUSTIC REQUIREMENTS
ACCORDING TO the DPCM of 5 December 1997
Index of the foot
traffic noise level
of floors (meas-
ured on site) L’n,w
63
55
63
58
58
55
55
45
A
40
35
30
25
20
B
160
140
120
100
80
60
42
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15
4
6
8 10
15
20
30
40 50
C
Legend:
A. Evaluation index of the attenuation of the sound pressure
level, ∆Lw, in dB
B. Mass per unit of area of the floating floor, in kg/m2
C. Dynamic stiffness per unit area, s', of the resilient layer,
in MN/m
3
