Comparison of sound insulation of windows with double glass units

Level of external noise grows every day in modern cities. New buildings usually have large windows or the whole areas of glass walls therefore protection from external noise is very important. Façade with good sound insulation properties is required to ensure acceptable internal noise level. Sound insulation of façade mainly depends from sound insulation properties of insulated glass unit (IGU). Different IGU with double, triple or even tetra glass could be used. In this paper is presented experimental study of window with three different type double glass units: 1 – two ordinary glass; 2 – one glass ordinary second one laminated; 3 – two laminated glass. The experimental results showed that sound reduction index (R) values are lower than 30 dB below frequency of 315 Hz (first type IGU), 250 Hz (second type IGU) and 125 Hz (third type IGU); sound reduction index (R) exceeds 45 dB above frequency of 4000 Hz (first type IGU), 2500 Hz (second type IGU) and 1600 Hz (third type IGU).