Sector Acoustic Criteria

Relevant Standards

There are many different standards that determine acoustic performance in buildings, be they legislative or guidance. The following list describes the most important areas in relation to the acoustic properties of the SAS product portfolio.



Commercial Offices

“Over a quarter (26%) of UK employees found the acoustics of their office unpleasant, and three-quarters (77%) of those blamed this on a noisy open-plan environment. A further quarter (27%) are frustrated by a lack of privacy.”  BCO (British Council of Offices) Making The Business Case for Well Being Study 2014  

Acoustics is one of the most important specification criteria for interior systems.  

The BCO provide a specification guide called the BCO Guide to Specification 2014 that includes reference and guidance for acoustic issues.

Typically guidance has concentrated on the issue of acoustic privacy between cellular office spaces, with guidance on cell office construction techniques with ceiling sound insulation values of 25dB or 35dB. BCO guidance also proposes some objective criteria, by way of reference to the recommendations set out in BS 8233:1999, which state that reverberation times in office areas, or other adjacent circulation spaces, should not exceed 0.4 seconds for fully fitted small rooms of 50m³ or 0.7 seconds for fully fitted rooms of 500m³.

The acoustic characteristics of open plan spaces do not follow normal rules for regular proportioned rooms, and the measurement of reverberation time in an open plan office can be misleading. It is better to follow the rule that optimum acoustic conditions in open plan office spaces are achieved when the suspended ceiling offers as much sound absorption as possible and certainly not less than 0.7αw.

Reverberation in offices, particularly large function spaces, is controlled by use of sound absorbent suspended ceilings. Fundamentally in commercial office interiors the suspended ceiling is the principle means of absorbing sound.

However, no guidance is offered on how to apply principles of sound absorption in offices that rely upon exposed soffits for thermal mass, those with no traditional suspended ceiling; in these cases, the use of acoustic baffles, acoustic rafts and acoustic wall panels can all help to reduce space reverberation time.



Educational Environments

Occupant comfort is an important factor of Indoor Environment Quality (IEQ) and sound reduction measures are an increasingly significant consideration. The Green Building Council has examined this in terms of the effect that poor acoustics, lighting and ventilation can have on health and productivity.

Worldwide studies have shown that excellent acoustics boost learning potential. Classrooms with poor acoustics can have a detrimental effect on children’s learning and development as well as possibly leading to associated voice and throat problems for teachers.

The UK Building Bulletin 93 (BB93): Acoustic Design of Schools published in 2014 by the Department for Education (DfE) provides a guide for the acoustic design of schools. Its requirements are mandatory, being referenced under regulation E4 of the Building Regulations 2000. Compliance with this regulation must be proved to the Building Control Officer by issue of a comprehensive design report – site testing is not required, although recommended.

BB93 applies to all primary and secondary schools. It does not apply to nurseries (unless part of a school), sixth form colleges (unless established as a school) or higher education facilities.

Table 1.5 of Part 1 schedules reverberation time targets that must be achieved in all school spaces, in the most part represented as limiting maximum values (except for corridors and stairwells where appropriate areas of sound absorption are defined by calculation).

Suspended ceilings or acoustic baffles, lighting rafts and wall panels with sound absorbent properties can be used as part of the overall interior design strategy to meet these targets, in combination with other room surface finishes.

"Design for good speech intelligibly in classrooms and lecture theatres" is recognised as one of the key aspects of BB93, as this is important not only for the obvious issue of pupil comprehension, but also to limit teacher fatigue. To this end, a mix of sound absorbent and reflective surfaces is recommended in order to promote good speech intelligibility.

Minimum requirements for sound insulation between classrooms and circulation spaces are also set out and specific advice is provided for any ventilation air path attenuators that are necessary.



Healthcare

Within healthcare environments occupant comfort is also receiving considerable attention with regards to assisting patient recovery times and privacy. The National Health Service (NHS) in the UK has provided guidance on these matters through its Health and Technical Memorandum 08–01 (HTM 08–01) published by NHS Estates. Internationally, these standards and the requirements of individual countries are driving changes and the specification of acoustic solutions within hospitals is growing.

HTM 08–01 sets out acoustic performance requirements to control room acoustics in sensitive spaces and advises that products achieving not less than Sound Absorption Class C should be provided that cover not less than 80% of the floor area.

For products that offer greater than Class C performance, it will be possible to provide a reduced area of treatment – advice should be sought from an Acoustic Consultant to properly quantify this.