Sound insulation of different types of shutters used in Jordan

Abstract

Window shutters, which are mainly installed in buildings for thermal accommodation, can provide appreciable external noise insulation. Five widely used types of these shutters were tested in a controlled laboratory environment similar to what might be encountered in the field. These shutters were subjected to a 1 3 octave band noise signal and traffic noise recorded and replayed using an open-close arrangement. Two types of window framing were tested, one with aluminium framing (slide leaves) and the other with plastic framing (openable leaves). The weighted sound reduction index of the window with plastic framing was 35 dB and that for the aluminium framing was 20 dB. The additional insulation provided by these shutters, when installed in front of plastic-framed windows, is in general negligible and only noticeable at high frequencies (above 1 kHz). If these shutters are used with aluminium-framed windows, they provide 10–15 dB of additional sound insulation in the frequency range 31·5 Hz to 8 kHz. Sound insulation of the shutters when the window is open is equal to 14 dB for the wooden shutter, 16 dB for the plastic shutter, 14 dB for the metal with foam shutter, and 20 dB for the plastic with foam shutters. Plastic-framed windows provide an insulation of approximately 37 dB averaged over the frequency range 100 Hz to 8 kHz based on 1 3 octave bands, while aluminium-framed windows provide an average insulation of 24 dB.