Introduction
In recent years there has been an increased interest in office buildings, factory spaces and
dwellings when the acoustics is of concern. It is acknowledged that reducing noise levels
in the living environment of people does improve the quality of life and also contributes
to an improvement in health. Legal requirements demanded by the authorities in various
countries cover a wide range of characteristics — noise levels, airborne and impact sound
insulation and reverberation time. In order to enforce such requirements, relevant
measuring procedures must be provided, formulated in national or international
standards. The international standards provided by ISO (International Standards
Organization) have reflected the trend mentioned above, increasing both in number and
covering broader aspects. On the European stage, the standard organization CEN has
been very active in bringing out standards as a follow-up to the EU directives. The
cooperation between ISO and CEN under the Vienna agreement has contributed
substantially to the creation of standards of general acceptance.
However, measurement procedures applied in the laboratory or in the field is just
one part of the story. Manufactures of building components and materials must have
harmonized and practically oriented test methods and other guidelines to meet the
regulatory requirements and consumer expectations in the quality of the products. This
again is the task of the standards organizations.
Controlling the acoustical conditions, be it in the sound insulation, reverberation
time or noise levels in a building or testing the acoustic properties of components in the
laboratory may certainly be complicated tasks even for qualified personnel. There is,
however, a problem area of another dimension than the above tasks — an accurate
prediction of the acoustic conditions and properties. Nowadays, there certainly is a
number of computer-based tools at the disposal of the building acoustics expert.
However, without a thorough understanding of the physical principles one may easily go
down the wrong track when new and novel constructions are needed. The author believes
that insight into the physical phenomena and the ability to convert the knowledge into
practical use is the mark of the expert, not a morass of lexicographical wisdom.
Furthermore, from the author’s point of view the concept of building acoustics
includes all types of acoustic and vibration phenomena related to buildings.
Traditionally, one might envisage that this concept is limited to sound insulation
problems in buildings whereas the design of rooms for proper conditions for music and
speech, i.e. room acoustics, is something else. In the English language, the concept of
architectural acoustics is often used to include all these aspects but in this book we shall
use the former notion. In addition to the subjects of sound insulation and room acoustics,
it would be natural to include all types of noise and vibration problems within the
concept of building acoustics, whether the sources are internal, e.g. building service, or
external, e.g. transport or industry. This book does not aim to do justice to all these topics
but concentrate on the acoustic performance of building elements and constructions, in
particular how they may be designed to obtain high sound insulation and absorption.
A chapter on room acoustics is also included but where large rooms are concerned
the applications are generally directed towards industrial spaces, not performance spaces
such as concert halls, theatres etc. This is a choice based on the experience that the reader
will have fewer problems in finding an extensive literature on the acoustics performance
of those rooms. As far as the noise and vibration aspect of building service equipment is