The internal environment is the focus of this second article about designing for noise to improve well-being. According to several recent studies, noise in cities has become an increasing hazard to health. Environmental noise, that is, noise from traffic, industrial activities, or amplified music, which reaches internal spaces, is not merely an annoyance. It has been linked to cardiovascular disease, diabetes, dementia, and mental health issues. As the world urbanizes, more people are exposed to excessive levels of noise. In medium- and high-density housing, in office buildings, and in schools, noise pollution can emanate from internal as well as external sources.
According to both the World Health Organization (WHO) and the European Environment Agency, at least 20% of the population of the European Union suffers from prolonged noise exposure. In Western Europe, this results in the loss of 1.6 million 'disability adjusted life years' (DALYs), or years of good health, per year. Noise levels at night are particularly problematic as they lead to sleep disturbance, which in turn can elevate the risk of developing anxiety and depression. The WHO recommends nighttime noise levels of a maximum of 30 decibels in bedrooms for quality sleep, a level which is often exceeded in urban environments.
In places of work and education, similarly, noise pollution can have a detrimental effect on mental health, concentration, and well-being. Sources of noise include traffic and airplanes, loud music, chatter in open-plan places, or impact sounds from adjacent properties. Design offers powerful solutions to minimize acoustic disturbances. Thoughtful architectural and interior design choices can significantly reduce noise, creating more comfortable and productive environments. In places of education, good internal acoustics also help with the audibility of the instructor.
External Noise Mitigation
The first line of defense from outside noise is the building envelope. For all building types, dense materials in the facade attenuate sound from entering, as can sound-proof windows with double or triple glazing. The position and orientation of the building can alleviate the necessity of high-performing acoustic materials, simply by facing away from sources of noise such as busy roads or railways. The need for adequate ventilation often conflicts with external noise attenuation, where open windows become a breach. Mechanical ventilation or acoustically insulated opening vents can be a solution.
Noise in Homes
Successfully eliminating unwanted noise within homes can have a profound improvement on occupants' well-being. Design strategies reduce the passage of sound from the external environment, from adjacent homes, and between spaces within the dwelling. Good planning can be very effective. Enclosing balconies to create winter gardens on noisy facades can help attenuate external sound. Placing bedrooms away from lively areas such as the kitchen and from lift shafts improves sleeping, while the rooms themselves can be separated by wardrobes and storage.
Preventing noise transfer between adjacent apartments involves reducing airborne sound and impact sound. Using density in separating walls and floors, such as with concrete, acoustic wool, and dense plasterboard, reduces airborne sound transmission. Impact noise is most commonly transferred through the floor and can be mitigated using floating floors and the use of rubberized acoustic layers in the floor build-up. Communal corridors and staircases can also be sources of noise, where the hard surfaces in these long spaces can amplify sound as it reverberates between them. Introducing soft materials such as carpets and acoustic absorbent ceilings and panels is a possible mitigator.
Noise in Offices and Schools
Internal sources of noise are perhaps more significant in these building types, especially with open-plan offices becoming more commonplace for their collaborative potential and low cost. Open-plan offices have received a good share of criticism due to their impact on well-being and productivity, mostly because of noise. There can be some mitigation by subdividing large spaces and by separating meeting and communal areas from quiet working spaces. Meeting rooms can be enclosed by walls and doors to contain any sound.
To reduce the inevitable hum of background noise, sound-absorbent materials can be used in the internal finishes. Ceilings are well-suited for this, where acoustic rafts, baffles, or acoustic ceiling tiles can form part of the strategy. Soft furnishings also act as sound absorbers. High-backed chairs, soft cubicles, and screens between workstations all help to subdivide the space further. Plants and internal greenery offer more sound absorption while simultaneously being visually pleasing.
Teaching spaces have similar acoustic requirements to office spaces. The impact of a noisy environment here can have a significant hindering effect on the education of children, with some estimates putting the loss of speech intelligibility at 33% of the content of a lesson. This is in addition to irritation and loss of concentration, with potential mental health issues developing. Improving the acoustics in a classroom focuses on the reduction of reverberation time. The use of absorbent materials, for example, on the ceiling or on the walls, can reduce this to no more than 0.6 seconds at mid-speech frequencies. This reduces the overall background noise of the room while making speech more intelligible.
A Holistic View
Controlling the level of noise in the internal environment is essential for well-being. This has to deal with both external and internal sources of noise, and is required in places of residence, work, and study. In all cases, there is a hierarchy of strategies, beginning with the building's positioning and orientation, through to the space planning within, the building technology and materials, and finally with the furnishings. When thoughtfully implemented, these measures can reduce the burden of noise-related health issues and foster environments that support rest, focus, and resilience
This article is part of the ArchDaily Topics: Building Wellbeing: Designing Spaces for Healing, presented in collaboration with the Hushoffice.
With its line of A-class pods Hushoffice helps create acoustically balanced workplaces that offer great environment for collaboration and focus, foster employee wellbeing, and accommodate the needs of neurodiverse staff, as well as employees with motor impairments.
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