Energetic and acoustic renovation of residential buildings of the 1950s to the 1970s

Abstract

One third of the residential buildings in Switzerland were built in the period from 1946 to 1980. Due to this large number buildings from the mentioned time period shape appearance of urban districts decisively in many Swiss cities. As these buildings do not fulfill current standards regarding energy efficiency, heat protection and sound insulation have to be renovated in the years ahead. To preserve the cityscape the renovation measures should be done with care and the outer appearance of the individual buildings should not be changed to a large extent. A research project with the title "Energetic and acoustic renovation of residential buildings of the 1950s to the 1970s" was carried out by the Department of Architecture, Wood and Civil Engineering of the Bern University of Applied Science (BFH AHB). The research project's objective was to reduce the lack of knowledge regarding the existing state of buildings from the mentioned time period in terms of energy performance and sound insulation. By means of statistical data, covering the residential building stock of the commune of Biel, reference building types for the 1950s, 1960s and 1970s were determined. In collaboration with housing cooperatives from Biel three representative residential buildings were selected and documented, one for each decade. As part of detailed structural survey of the existing buildings the energetic and acoustic values and properties regarding the reference building of the 1950s as well as the reference building of the 1960s were determined. Amongst other things the constructions of the components were inspected in a non-destructive way and the heat transfer coefficients of the heat transferring components were calculated. Blower door tests to evaluate the air tightness of the building envelopes as well as acoustic measurements for determining the impact sound protection and the protection against airborne noise were done. Within the research project exemplary concepts for gentle energetic and acoustic renovations were developed for the two reference buildings. In this paper the research project's results with main focus on the reference building of the 1950s are presented.