Soundproof and acoustic glazing
Increasing levels of acoustic pollution in both residential and industrial area, request high performances to windows also in terms of noise insulation. Reducing nuisance reduction generated by cars, trains, planes and human activities improves our quality of life. Italian laws specify maximum sound levels and consequent façade acoustic insulation figures. These values require a minimum attenuation of 40 dB for residential buildings, 42 dB for offices and shops, 45 dB for hospitals and 48 dB for schools. But how can we unite light ans silence?
We usually make an acoustic glazing with panes of different thickness in order to improve attenuation and thermal insulation at the same time. Anti noise glass are laminated panes with an optimized PVB (polyvinyl butyral) film called acoustic PVB for its insulating properties. These panes are usually available in 3+3, 4+4, 5+5 and 6+6 mm, united by a PVB film 0.38, 0.76 or 1.52 mm thick. This film can also be painted as in gray or bronze glass, or as in the dark band on the top part of windshields.
Soundproof glass must be chosen according to the kind of noise to be attenuated: a road or a railway emit low frequencies, while planes and industrial plants emit noise at higher frequencies. Performances of these glazings can be surprising: an krypton-filled 4+4/16/6+6 double glazing can reach a 50 dB attenuation, that is a reduction of about 10,000 times.
Best help in noise reduction comes from a window with appropriate insulating figures. However, with regard to both acoustic and thermal insulation, we must not void advantages provided by an optimized glass with an inaccurate installation. A perfect setting is obtained with a counterframe, using specific products for acoustic attenuation, like expanding foam tape and acoustic foams.