Education & Health & Justice
Studies have shown that poor acoustics in classrooms have a detrimental effect on learning. It is vital that the latest guidance is used so that the level of speech intelligibility between teacher and pupil is optimised by considering sound insulation between spaces, mid-frequency reverberation times, indoor ambient noise levels, sound absorption in circulation spaces and the special needs of spaces for children with hearing impairments.
The implementation of the Approved Document E of the Building Regulations (which came into force in England and Wales in July 2003) made it a mandatory requirement to consider the acoustic design of new school buildings in accordance with Building Bulletin 93 Acoustic Design of Schools – A Design guide (BB93). However, the demonstration of compliance with BB93 through commissioning was not mandatory and the requirement to do so was dependent on the type of contract between developer and funder.
To ensure that your school is acoustically fit for purpose, it is important that you appoint a suitable qualified acoustician who can take you from feasibility through to handover. Typically the acoustic design will start with an acoustician looking at the orientation of the building and the ‘zoning’ of sensitive teaching spaces further away from external noise sources. A noise survey at the proposed school location will also help determine a suitable facade strategy. Other design advice would follow, such as a review of constructions for adequate sound insulation between spaces and surface finishes so that teaching spaces are not overly reverberant, ensuring good speech intelligibility between teachers and pupils alike.
Many ANC registered acoustic consultancies also offer three dimensional computerised modelling to determine the level of reverberation or speech intelligibility in large or unusually shaped spaces such as multi-purpose halls.
The ANC recognises the importance of good acoustics in schools and have put in place The ANC Good Practice Guide (GPG) which aims to standardise the test method for demonstrating that schools comply with requirements. Indeed the ANC have gone one step further with the proposal of The Schools Testing Certification Scheme, a testing scheme that would be recognised should commissioning be mandatory in the future.
Currently the main guidance document for schools is Building Bulletin 93 Acoustic Design of Schools – A Design guide (BB93) 2014 and for PSBP contracts the earlier Acoustic Performance standards for the Priority Schools Building Programme introduced in September 2012.
Whether it be a walk-in health care centre or a hospital it is important that new healthcare developments have good acoustic conditions to maintain privacy and good speech intelligibility for users, and to aid in the recovery of patients. Health Technical Memorandum 08-01: Acoustics sets out acoustic design targets and practicable ways of meeting these targets whilst considering many other design drivers such as retaining hard (reflective) hygienic surface finishes in operating theatres.
HTM 08-01 provides guidance on the layout of healthcare buildings, airborne and impact sound insulation of partitions, construction specifications, detailing, services penetrations and mechanical services noise, as well as external noise break in and environmental noise impact.
Like schools, credits sought under Building Research Environmental Assessment Method (BREEAM) can be important design drivers too. So that you maximise the quality of the internal acoustic environment in your health care building make sure that you appoint an ANC listed acoustician.
Court and prison buildings need high levels of speech privacy between spaces in addition to good levels of speech intelligibility within spaces. Poor speech privacy could mean important legal arguments are overheard and a case is ultimately compromised; the same could apply to interview cells. In court it is important that all speaking members are not only heard but also understood; any information misconstrued could have a significant impact on the case being heard. It is therefore important that the acoustic design of these buildings is seriously considered in conjunction with other design drivers such as security.
So whether your development is driven by Courts Standard Design Guide 2010, Police Building Design Guide or is contractor lead, make sure you have a suitably qualified ANC acoustician in place from the start.