Finnish Handbook for Dimensioning of Sound Insulation of Building Facades

A handbook for the dimensioning of the sound insulation of building facades has been published in autumn 2003 by Ministry of the Environment of Finland [1]. The publication discusses the signs and symbols used in land use plans, as well as plan regulations, to indicate sound insulation requirements for building facades. It describes how these requirements are laid down and presents calculation methods for use in dimensioning of the sound insulation of building facades. The method aims to ensure that the required minimum sound level differences are achieved in the majority of cases, and there should be no need for in situ sound level or sound insulation measurement. The use of this method does not guarantee that the target value for indoor noise is reached in all cases. The method enables the builder to choose façade components and specify their sound insulation at early stage of the designing, and to show that the building shell fulfils the requirement. For the authorities the method gives the possibility to ensure that the indoor noise stays at a satisfactory level. The dimensioning of the façade for different kinds of noise incidents is a problematic task. This paper describes the published design method, the special features taken into account and how some problems are tackled. Since nowadays the design methods, concepts used for sound insulation etc. vary very much in Europe, this presentation tries also to arouse discussions which in turn may lead to a more comprehensive and coherent harmonisation in the future.