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SEEN BUT UNABLE TO BE HEARD: OPTIMISING THE ACOUSTICS OF EDUCATIONAL SPACES

INTRODUCTION

The importance of early childhood development for later success, health and emotional wellbeing is undeniable. While ‘nature’ will always be an important part of who we are, ‘nurture’ has been receiving significant recognition for its role in an individual’s development throughout life, with the largest impact on personality being attributed to “largely unknown environmental influences”.1 While the specific influences of early childhood development may be unique to each individual, ensuring exposure to beneficial environments and well-designed architecture is comparatively a relatively simple step, and one that is crucial in determining how children grow.2

People may not necessarily agree on an exact definition of well-designed architecture from the perspective of form, but the end-user is an imperative consideration irrespective

A REVIEW OF THE STANDARDS

The Australian Standards, a non-binding but widely accepted set of standards for Australian construction, recommend in AS/NZS 2107-2016 that teaching spaces and single classrooms operate within the range of 35-45dB, with “minimal reverberation times”.3 This is both for the purpose of noise control as well as for the benefit of students with learning difficulties and students with English as a second language.4 The Association of Australian Acoustical Consultants (AAAC) go into more depth with acoustic recommendations in their Guideline for Educational Facilities’ Acoustics, and are more stringent with their results, recommending a peak of 35dB for standard classrooms and 30dB for teaching spaces with hearing impaired students.5 The AAAC also highlights specific maximum reverberation times.6 These figures may not be static, however, with one study suggesting through collated standards internationally that younger children are more susceptible to higher levels of noise.7

Despite these recommendations, further studies have shown classroom levels far exceeding any of the recommended levels, particularly within open plan classrooms.8

Poor acoustics in educational environments can compound everyday

stressors associated with teaching (and

learning), detract from early development among

students and result in numerous other issues

for the end-users.

of stylistic choices. There is increasing evidence linking acoustics to functionality, and while acoustics may have once been an unknowable factor within architecture and design, this is no longer the case. Rather, it has become an aspect of design that should be addressed sooner rather than later. In order to achieve optimal soundscapes and match acoustics with design intent, it is necessary to engage with suitable methods, products and adequate detailing as a part of a combined approach.

One consequence of not meeting these needs include jeopardising the final functionality of the space. Poor acoustics in educational environments can compound everyday stressors associated with teaching (and learning), detract from early development among students and result in numerous other issues for the end-users.

On a day-to-day basis, excessive noise in the classroom can lead to a number of short-term problems. Teachers working in classrooms with a reverberation time of greater than 0.5 seconds have shown greater stress levels, whilst excessive noise has been linked to a reduced ability in students “to understand teachers’ spoken instructions and absorb written information.” ,9,10 Outside noise increased students’ dissatisfaction with their classrooms and excessive noise was linked to stress within students as well, while the presence of less external noise can be connected to higher student achievement.11 The sources of noise include anything from

fellow students (particularly in open plan classrooms, where one cannot control the activities of other groups), air conditioning, road traffic and planes overhead.

Proving to be more than just everyday annoyances, these same impacts over time can lead to long-term problems as well. Teachers consistently report more voice problems than the general population, and almost fifth of teachers have missed at least one day of work because of those problems.12 When it comes to students, a 20dB increase in either road or air traffic can delay the reading age of a 9-10 year old by up to eight months.13

THE IMPACTS OF NOISE IN THE CLASSROOM

MANAGING NOISE IN THE CLASSROOM

There are two primary ways of managing noise levels in the classroom. The first is to block external noise from entering the space, relying on materials with a high R-value. These include dense materials such as concrete or acoustic insulation in the walls, and methods such as ensuring all potential gaps are sealed off. Windows are often primary points of entry for intrusive noise. However, by swapping single glazing for double glazed windows, the R-value of windows can be significantly improved.

While higher R-values will prevent airborne noise from entering spaces, preventing structure-borne noise requires the separation of elements that would otherwise allow vibrations to carry through the structure. Preventing both airborne and structure-borne noise requires adequate detailing and correct construction practices, along with the specification of satisfactory materials.

The second method of managing noise levels in the classroom is to reduce reverberation levels through the installation of absorptive materials. While hard materials such as concrete and steel will cause sound to bounce around the room for longer, leading to increased reverberation times, soft materials will reduce reverberation. However, reverberation is affected by the surfaces present in a room, and not the density or thickness of them as would be considered when blocking sound. Every surface in a space affects the reverberation time, from the walls, floors and ceilings to the windows, desks, chairs and even people present in the room. Carpet, curtains, padded seats and people are all examples of absorptive surfaces, which will reduce the overall reverberation time. Acoustic wall panels or ceiling products are also specially designed to reduce reverberation in a room, and are generally more effective than incidental materials.

Reducing reverberation improves the intelligibility of speech, although it should always be done to a level that makes sense for the purpose of the space. As suggested by the aforementioned standards and studies conducted, a reverberation time of less than half a second is best to ensure the wellbeing of a classroom’s occupants, as well as maximising their comprehension of spoken instructions.

When specifying materials that will ultimately affect a space’s final soundscape, it’s important to keep in mind aesthetics and the overall design intent. There’s no purpose to creating the ideal acoustic environment if it’s still an unpleasant space to occupy for other reasons. For the same reason, maximising the effectiveness of a classroom can only be done when considering the needs and preferences of the target audience. Simple elements such as colour are an easy way to engage children and enhance learning environments, as well as preventing a space from feeling sterile.

The psychology of colour in education environments is a well-documented topic, with certain shades being associated with specific atmospheres. Blues are often associated with calmness and increasing concentration, while shades of yellow are typically seen as being more appropriate for language and creative pursuits.14 Greens are suitable for creating a sense of balance between the former two and warmer colours such as oranges and reds are more fitting in environments intended for physical activity, given their potential to overstimulate.15 Any leading supplier or manufacturer can most often customise the colour and appearance of acoustic wall and ceiling treatments without hassle, allowing for specific design intentions to be met.

A space’s intended use is also crucial to consider when designing the layout of an educational facility. In order to maximise the effectiveness of acoustic solutions, it is best practice to avoid positioning spaces that demand quiet, such as classrooms and libraries, next to spaces that typically have no acoustic demands, such as canteens or gymnasiums. However, even the design of the classroom will need to be taken into account, with the acoustic demands of open plan classrooms being harder to meet than their individual counterparts, despite being popular for other reasons. Making decisions around these various factors require a weighing up of whatever is the most important, along with other constraints such as budget, size and time.

OTHER CONSIDERATIONS FOR ACHIEVING THE BEST ACOUSTIC SOLUTION

CSR Himmel Interior Systems are Australia’s leading brand in acoustic and aesthetic solutions. As an amalgamation of Ceilector Ceiling Solutions and Alsupply Aluminium & Hardware, Himmel represents a complete interior systems offering, with products suitable for any interior space.

Products available in the Himmel range have featured in a number of educational facilities around the world including Darwin, Australia, Portsmouth in the UK, a university in Spain and a primary school in Germany.

Himmel’s acoustic ceiling and wall panels are available in a variety of sizes, materials and appearance in order to match all design briefs, and further customisations are available in product profiles and finishes. Bespoke solutions are also available for any particularly challenging brief. Backed up by the CSR group, customers can be assured of the high quality of Himmel’s products and services.

For more information, visit Himmel’s website via the URL below. www.himmel.com.au

CSR HIMMEL

www.himmel.com.au

REFERENCES1 “11.3 Is Personality More Nature Or More Nurture? Behavioral And Molecular Genetics”. 2010. In Introduction To Psychol-

ogy. University of Minnesota Libraries Publishing. http://open.lib.umn.edu/intropsyc/chapter/11-3-is-personality-more-na-ture-or-more-nurture-behavioral-and-molecular-genetics/. Creative Commons License (CC BY-NC-SA 4.0), https://creative-commons.org/licenses/by-nc-sa/4.0/).

2 “The Importance Of Early Childhood Development”. 2017. Aedc.Gov.Au. Accessed September 5. http://www.aedc.gov.au/parents/the-importance-of-early-childhood-development.

3 Standards Australia and Standards New Zealand. AS/NZS 2107-2016: Acoustics – Recommended design sound levels and reverberation times for building interiors. Homebush, Australia: Jointly published by Standards Australia and Standards New Zealand, 2016. https://infostore.saiglobal.com/en-au/Standards/AS-NZS-2107-2016-1882409/

4 Ibid.

5 Association of Australian Acoustical Consultants. 2010. Guideline For Educational Facilities Acoustics. Association of Austral-ian Acoustical Consultants. http://www.aaac.org.au/resources/Documents/Public/AAAC%20Educational%20Buildings%20Acoustic%20Design%20Ver%201.pdf.

6 Ibid.

7 Mealings, Kiri. 2016. “Classroom Acoustic Conditions: Understanding What Is Suitable Through A Review Of National And International Standards, Recommendations, And Live Classroom Measurements”. In Acoustics 2016: The Second Australa-sian Acoustical Societies’ Conference. https://dspace.nal.gov.au/xmlui/bitstream/handle/123456789/521/Acoustics2016%20P145_RevisedPaper_Mealings_5_rev.pdf?sequence=1.

8 Mealings, Kiri Trengove, Jorg M Buchholz, Katherine Demuth, and Harvey Dillon. 2014. “An Investigation Into The Acoustics Of An Open Plan Compared To Enclosed Kindergarten Classroom”. In International Congress On Noise Control Engineering. Toowong, Qld: Australian Acoustical Society. http://hdl.handle.net/1959.14/340315.

9 Tiesler, Gerhart, and Markus Oberdörster. 2006. “Noise - A Stress Factor? Acoustic Ergonomics Of Schools”. In Euronoise 2006. http://www.acousticbulletin.com/EN/SS07-014.pdf.

10 Biamp Systems. 2013. Building In Sound. Biamp Systems. http://www.airport-technology.com/downloads/whitepapers/public-address/building-in-sound/.

11 Schneider, Mark. 2002. Do School Facilities Affect Academic Outcomes?. Washington, D.C.: National Clearinghouse for Educational Facilities. http://www.ncef.org/pubs/outcomes.pdf.

12 Roy, Nelson, Ray M. Merrill, Susan Thibeault, Steven D. Gray, and Elaine M. Smith. 2004. “Voice Disorders In Teachers And The General Population”. Journal Of Speech Language And Hearing Research 47 (3): 542. doi:10.1044/1092-4388(2004/042).

13 Clark, Charlotte, Rocio Martin, Elise van Kempen, Tamuno Alfred, Jenny Head, Hugh W. Davies, Mary M. Haines, Isabel Lopez Barrio, Mark Matheson, and Stephen A. Stansfeld. 2006. “Exposure-Effect Relations Between Aircraft And Road Traffic Noise Exposure At School And Reading Comprehension: The RANCH Project”. American Journal Of Epidemiology 163 (1): 27-37. doi:10.1093/aje/kwj001.

14 O’Brien, Sylvia. 2014. “Psychology Of Colour In The Educational Environment”. Colorobjects.Com. http://www.colorobjects.com/en/color-columns/the-colour-real/item/357-psychology-of-colour-in-the- educational-environment.html.

15 Ibid.