Logo TFI

Development of an innovative system of textile impact sound insulation and screed for the acoustic renovation of old buildings (textile impact sound insulation)

The reduction of indoor noise is of great importance for the perception of comfort, efficiency and health. Due to the increasing energetic refurbishment of buildings, sound from outside penetrates only to a reduced extent through facades, doors and windows. As a result, the basic noise level can fall below the hearing threshold, while the sound inside the building is simultaneously reinforced and perceived as disturbing. This effect is increased by the trend toward hard floors. Textile floor coverings, which significantly reduce impact sound, are being replaced by laminate and wood flooring. Impact sound thus increases and is perceived as disturbing.

Especially in buildings from the post-war period up to the 1980s, impact sound insulation is a neglected issue, resulting in a need for renovation systems for retrofit impact sound insulation.

In addition to the requirements for impact sound insulation, systems for retrofitting impact sound insulation must also meet requirements for low mass due to structural reasons and a low installation height to maintain connection dimensions.

The low height and associated mass of the systems developed in this research project pose challenges to the spring properties of the impact sound insulation.

The aim of this research project was to develop a textile impact sound insulation (TTD) for the refurbishment of old buildings, which is permanently installed together with the screed (

Dry screed flooring board on textile impact sound insulation during measurement of impact sound insulation in the TFI building acoustics laboratory.


For this purpose, in addition to a specification sheet, a calculation model was created at the beginning of the project, which formed the basis for the first developments of the TTD. The TTD developed in the project, together with 23 mm thick dry screed flooring boards, reaches impact sound reduction (ΔLw) between 19 dB and 25 dB with a maximum thickness of the TTD of 10.5 mm.

To reduce compressibility, tufting structures with reinforcing areas made of particularly bend-resistant yarns (3300 dtex, 8f) were developed. This allowed the compressibility to be reduced to a standard-required level of

Funding program and project number

IGF 20301 N


01.01.2019 – 30.09.2021



Christian Goetz

Phone: +49 241 9679-160



Subscribe to our newsletter here!

Subscribe now