ACOUSTIC FALSE CEILING IN WIDE ROOMS, REALIZED BY AN INNOVATIVE TEXTILE SYSTEM

Abstract

The aim of this article is the study of wide rooms’ acoustic false ceilings. In order to improve indoor acoustic comfort, it is possible to install an acoustic false ceiling. Many technical solutions are used to improve the inner room quality in terms of reverberation time and speech intelligibility. Restaurants and dining halls often can have acoustic problems caused by uncontroll ed background disturbing noise. Indoor comfort can be seriously impaired in crowded rooms with many speakers, such as in restaurants and dining halls: the background noise produced by people talking damages the speech intelligibility level. If the speaker cannot be hea rd by his listener, he will speak louder. The speaker’s increasing voice power will gradually intensify the background noise producing a domino effect (cocktail party effect). In this case study we show the use of a brand new textile false ceiling system. This solution has just been installed in the Centre Hospitalier Universitaire Vaudois (Lausanne) new restaurant (1800 m 2 ) that can host 800 people. The innovative textile system, designed for this project, is composed of an aluminium structure within a shaped rock wool panel, enfolded by stretched EPS “acoustically transparent” fabric. This system, suspended from the ceiling and held by metallic lateral supports, improves the room acoustic quality, creating a nice dynamic effect as well. The installation of this system began in July 2014 and was completed in April 2015. We used the CATT-Acoustic software to analyse the room acoustic behaviour, the reverberation time and speech intelligibility. Keyw ords: acoustic false ceiling, textile false ceiling systems, indoor acoustic comfort, speech intelligibil ity, reverberation time.