A quiet place

Steve Smith of Knauf Insulation explains why a happier, healthier home starts with a quiet building.

With people living in closer proximity to industry, infrastructure and each other than ever before, it’s no surprise that complaints about noise are rising. At the same time, how we use our homes is changing. In 2017, 1.6 million people worked regularly from home, and a further 4 million workers wish to do so. As a result, the issue of noise pollution and good acoustics within the home has never been so important.

But noise is far more than just an annoyance. In recent years, there has been a growing body of research that has linked noise to poor health. In fact, incidence of heart attack increases at 60 dB, and people living on a busy road or near an airport are 25 per cent more likely to experience depression. People subject to noise are also more likely to suffer from stress, poor sleep, and a loss of concentration.

Taking these points into consideration, it stands to reason that designing our homes to offer better protection from unwanted noise will contribute to the economy through a reduction in sickness, lower healthcare costs, increased productivity and enhanced wellbeing.

There are three aspects to consider when designing a home with good acoustics. Firstly, reducing the impact of noise from outside of the home. Secondly, preventing noise made by its occupants from affecting its neighbours, and vice versa. And finally, with regards to internal acoustics, and preventing sound transfer within the building itself.

Approved Document E (Part E) of the Building Regulations (England and Wales) sets out the acoustic performance requirements of residential dwellings in order to protect residents from unwanted sound. This states the level of sound insulation that must be achieved within walls and floors that separate dwellings such as semi- detached houses or flats, and for walls and floors separating bedrooms and bathrooms within a dwelling.

However, there is an argument that Part E doesn’t go far enough. For example, in Scotland, the minimum sound insulation requirements are more stringent than in England and Wales. It is therefore quite possible that regulations relating to acoustics could form part of wider reforms to Building Regulations.

Good acoustics also have resonance with home buyers, and could be used to create a truly unique selling point for the housebuilder.

Consider for a moment a scenario that takes place in homes up and down the country. One parent is listening to music while cooking in the kitchen, two young children are squealing with excitement in the play room, and a third is playing computer games in the living room. All of which create a distracting cacophony for the other parent trying to work in the study because no sound insulation is required between these rooms.

Furthermore, the minimum standards for sound insulation set out in Part E do not protect a home’s occupants from external noise from traffic, planes or trains – arguably the most damaging to our health.

Choosing to add acoustic mineral wool insulation to internal walls and partitions not covered by Part E would make a huge difference to family life, yet could cost as little as £30 more for a three-bed house, with no increase in mass and very little additional labour.

Where external walls are concerned, brick-built constructions generally achieve good acoustic performance thanks to their mass. Other construction methods such as timber frame or rainscreen generally achieve better thermal performance than masonry walls of comparable thickness. However, the reduced mass  means an acoustic solution is also required to protect occupants from external noise such as road or flight noise, and that from surrounding properties.

Acoustic mineral wool insulation, is not only non-combustible while offering good thermal performance levels – it will also achieve high levels of acoustic performance. However, if they choose non-absorbent materials for thermal insulation, they may also need to specify a separate acoustic solution.

It is important to remember that, as with thermal and fire performance, not all insulation is equal where acoustics are concerned. For example, PIR insulation has a closed cell structure and therefore has very limited sound absorption qualities. There is also a misconception that rock mineral wool offers superior acoustic performance to glass mineral wool, but recent research has shown them to perform equally in most applications.

When choosing a solution, it is very important to specify a product designed to provide acoustic performance. Many people believe that mineral wool loft insulation products, which are designed for thermally insulating lofts, will also offer good acoustic absorption. However, this is not the case, because loft insulation products are not designed to provide high levels of acoustic performance.

If there’s one thing that’s loud and clear, it’s that good building acoustics are going to become an increasing priority for legislators and home buyers alike. Those housebuilders who incorporate good acoustics into their design will be ahead of the competition, giving them a benefit they can really shout about!

Steve Smith is head of product management and business intelligence at Knauf Insulation