Funds: Commission for Technology and Innovation KTI

The low quality of impact sound insulation of wooden floor slabs is a major obstacle to an enhanced use of timber-frame structures in multi-storey buildings. The theoretical investigation of vibration transfer through such slabs has shown a multi-layer structure with the layers out of tune and also an immediate conversion of the vibration energy into heat to be necessary. On this base, a real quantum jump in impact sound insulation has been realised with the aid of granular materials (sawdust): standard impact noise levels as low as 56 dB and 42 dB (with carpet) were attained (concrete slab 20 cm: 70 dB, 25 cm: 66 dB). A patent has been assigned. Further optimisation as well as the transfer into practice are in process.

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