The Sound of Silence & Noise in a Built Environment
Posted in Acoustic Consultants News on Aug 03, 2018
There's no denying that the general public is becoming more and more aware of noise in the environment. Although only 8% of land in the UK is taken up by cities, 54% of the population lives, and 60% works, in a city. It's not only cities where the impact is felt either. Even in relatively small towns and villages the shortage of available building land leads to in-filling and knocking down houses to build flats in their place; all of which increase population density.
An inevitable impact of that increasing density is more noise from neighbours, traffic and other sources. The trend is to regard noise as a nuisance though, rather than a serious issue on the same scale as air pollution or energy conservation. Certainly, changes to building regulations in recent years have focussed more on energy efficiency and safety than noise insulation.
But new and better-developed building materials offer increased acoustic insulation and enable buildings to factor noise in from core design through to build.
The personal price paid for excessive noise
Noise is an issue for people when it prevents them from being able to sleep or focus on learning, work or even their social lives.
European Environment Agency (EEA) studies discovered that people experiencing noise levels above 40dB while sleeping (the highest level recommended by the World Health Organisation (WHO) outside a bedroom) will be disturbed and wake up during the night. Those experiencing levels above 55dB can suffer from high blood pressure and heart disease.
A UK study published in 2015 by the University of the West of England looked at the effect of noise on problems known to be exacerbated by high blood pressure. It concluded that high levels of noise exposure had resulted in increased cases of dementia, strokes and heart attacks and that the probable cost to the country was around €1.34 billion.
Overall, a WHO study revealed that up to one million healthy life years are lost each year in Western Europe as a result of over-exposure to noise in the environment, making it second only to air pollution as an environmental factor contributing to ill health.
There are other health issues apart from those caused by high blood pressure. Tinnitus caused by traffic or leisure noise is becoming more common and is believed to cost the UK £52 million every year, in terms of demand on health services and lost productivity. Hearing loss from loud music costs an estimated £52 million and the cost of slower learning in children from excessive day and night-time noise is believed to be £252 million.
Nuisance and disturbances
There's considerable disruption on a social level too, with noise behind many complaints about anti-social behaviour. Monitoring and responding to these complaints is the responsibility of the local authority and the cost averages out at between £180 and £360 per incident for the local authority. It also, of course, causes distress and waste time for the complainant.
A case study of noise complaints by Westminster City Council showed the percentage of noise for the top five causes for complaints in 2008 were split as follows:
- 48.4% - Residential noise (neighbours)
- 17.9% - Noise from commercial premises
- 11.1% - Building sites
- 10.5% - Noise in streets
- 7.5% - Burglar alarms
It was also observed that, for all complaint types apart from building site noise, complaints peaked between 8pm and midnight and at weekends, showing that residents were most likely to be affected by noise when trying to sleep, or get children to sleep.
Hotels are also putting more effort into sound insulation when building or refurbishing, then referring to it by featuring the benefits of a good night's sleep in their marketing. The rise of TripAdvisor has played a huge part in advertising the poor quality noise insulation of individual establishments to a global audience.
This all demonstrates that people are becoming more and more aware of the impact of noise in the built environment. A few decades ago, having an energy efficient property would not have been a particular draw for buyers. But after ten years of steep energy price rises, it certainly is now. As awareness of the nuisance of noise increases, built-in acoustic insulation is likely to become a larger factor in house buying.
Commercial buildings such as office, factories, schools and health establishments can also benefit from having acoustic properties considered at the design stage. The benefits of quieter schools, offices and buildings associated with health care, such as hospitals, nursing homes and surgeries, are obvious to anyone who's looked at the WHO and EEA studies referenced above.