SOUND INSULATION OF DIFFERENT TYPES OF SHUTTERS USED IN JORDAN

Window shutters, which are mainly installed in buildings for thermal a ccommodation, can provide appreciable external noise insulation. Five widely used types of these shutters were tested in a controlled labora tory environment similar to what might be encountered in the field. Th ese shutters were subjected to a 1/3 octave band noise signal and traf fic noise recorded and replayed using an open-close arrangement. Two t ypes of window framing were tested, one with aluminium framing (slide leaves) and the other with plastic framing (openable leaves). The weig hted sound reduction index of the window with plastic framing was 35 d B and that for the aluminium framing was 20 dB. The additional insulat ion provided by these shutters, when installed in front of plastic-fra med windows, is in general negligible and only noticeable at high freq uencies (above 1 kHz). If these shutters are used with aluminium-frame d 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 wh en 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 rang e 100 Hz to 8 kHz based on 1/3 octave bands, while aluminium-framed wi ndows provide an average insulation of 24 dB.