New builds are required by most planning authorities to meet the acoustic BS 8233 standard. This standard was published in 2014 in response to the plethora of residential properties constructed/converted from pre-existing buildings being developed within noisy urban densely populated areas.
M.L. Duong
The past decades have seen a trend towards glass buildings. These designs offer interiors full of light, often with breath-taking panoramic views. One of the weakest components of a building in terms of noise mitigation is its windows. In terms of acoustic integrity these glass heavy designs amplify the urban soundscape.
Curtain walling and large quantities of glass are both challenges to the acoustician. Glazing a curtain wall construction requires the primary units to be attached to the metal/concrete structural frame of the building. This method of attachment means that
these hotel windows lack the properties of their more traditional cousins fixed into timber grounds, which serve as an effective dampener to sound waves.
With the increasing amount of development on noisy brown field sites, coupled with the ‘en vogue’ glass heavy designs, specifiers are under a lot of pressure to create quiet internal spaces, to satisfy the needs requirements of the occupiers and building owners.
Through the din, developers and planners cling to building standards, both legislative and non-legislative. From the non-legislative guidelines planners can choose additional, more stringent acoustic standards for new developments. Often developers will add their own requirements, superseding requirements from the planning authority.
In the case of this Treatment of the Month, the hotelier required the contractor to achieve The World Health Organisation (WHO) recommended levels: (30 – 35 dB) for all its bedrooms, rather than settling for the BS 8233:2014 (45 – 55 dB) hotel bedroom requirements.
Room |
Noise Level |
Bedrooms |
30 - 35 dB |
Music rooms |
30 - 35 dB |
Living rooms |
30 - 40 dB |
Classrooms/meeting rooms |
35 - 40 dB |
Libraries |
35 - 40 dB |
Open offices |
45 - 50 dB |
This brand new hotel had been installed with double glazing specified to achieve these levels. However in order to meet the needs of the architect’s design, the contractor was forced to choose a glazing product known to be working at the very limits of its acoustic capabilities. This resulted in the building failing its acoustic tests a situation which can spell disaster for a contractor.World Health Organisation - reasonable noise levels
Series 41 Acoustic secondary units - open and shut
Selectaglaze was called in to design a retrofit solution, which in this design of building can be limiting and cause difficulties.
Ideally, a secondary glazing unit should be installed in such a way that it is independent of the primary. However, for this project, Selectaglaze was required to design a solution where the secondary glazing was attached to the primary window.
Although not the optimum installation method, the quality of the series 41 acoustic secondary units combined with the primary window resulted in the building passing the all-important acoustic tests and the guests at the hotel having a peaceful and good night’s sleep.