TempSchall

The requirements for the airborne sound insulation of external building components are defined in DIN 4109-1. The requirement is based on the use of the room and the external noise level. In the new version of DIN 4109-2, an additional explicit consideration of the external noise level at night was introduced. If the external noise level at night is not more than 10 dB lower than during the day, the sound insulation is calculated using the relevant external noise level at night plus an additional 10 dB to take into account the increased nocturnal disturbance effect in bedrooms.

The sound insulation of a window can be significantly improved by an external, closed closure (roller shutter, window shutter). This eliminates the need for costly additional measures on the window itself, so that required sound insulation at night in bedrooms can be confirmed at low cost.

To what extent can night-time sound insulation be improved by external closures? Which parameters determine the level of improvement? Can the improvement be determined from the design features of the external closure? How can the results be standardised?

By means of experimental (measurements in window test stand according to DIN EN ISO 10140) and numerical investigations (finite element models) on the airborne sound insulation of windows in connection with external closures, a component catalogue is to be developed on the one hand, and on the other hand the basics for understanding the acoustic relationships are to be recorded. This data can then be used to develop a calculation model for calculating the resulting sound insulation of windows with external closures. The single-number values (weighted sound reduction index) generated in this way will then be used to provide the necessary proof of sound insulation.

The results are to be used to provide data in the DIN 4109 component catalogue for the mathematical verification of sound insulation against external noise, taking external closures into account. Furthermore, a simple, manageable calculation rule is to be developed, which will then be standardised in DIN 4109.