Acoustic performance of double panels in closure systems with point connections

Resumo

The transmission loss (TL) that occurs though closure system panels used in construction buildings is
a parameter used to evaluate it acoustic performance. TL depends on the frequency of the incident sound, the
type of fixation of the panels to the structure as well as other factors and its curve can be obtained through tests
or graphic methods based on empirical formulation, which can be converted into computational models. In this

work, TL is evaluated in compositions of double closing systems and the highest TL correlated with the Line-
Line (LL) connection is verified, which is when the panel is directly fixed to the metal profile of the closing

system on both sides. Double panels composed of expanded polystyrene (EPS), plasterboard (GEA) and
cementitious board (PLC), with glass wool (LVI) in the air cavity between the panels, are analyzed. Simulations
are performed in a computational model, based on a graphic method, developed to estimate TL in single and
double panels. The frequencies of 500, 1000 and 2000 Hz are considered. It is verified that the EPS panel
provides higher TL values of 68dB, 74 dB and 80 dB for the respective frequencies. The GEA panel presented
values of PT of 47 dB, 52 dB and 43 dB, respectively. Furthermore, the PLC panels presented TLs of 57 dB, 63
dB and 69 dB. Therefore, the EPS double panel is the one that provides the best acoustic performance in terms of
sound transmission losses at the frequencies considered. The computational model could help in the
determination of this parameter in double panels, interspersed with glass wool and Line-Line connection,
allowing a quick analysis of the acoustic performance of the panels.