Making more noise?

Phil Brown, European regulatory marketing manager at Pilkington UK, discusses how a new international standard could lead to an uptake in noise-control glazing.

Do you know how quiet your home is? You may well do in the future, as a new international standard for classifying the sound insulation in dwellings is currently in development.

This could mean we start to see noise control ratings for residential properties in the same way that homes are issued with an Energy Performance Certificate, which appears on the estate agent’s description at the time of sale.

‘ISO 19488 Acoustics – Acoustic classification scheme for dwelling’ could introduce a classification scheme to make it easier for developers to specify sound insulation for new-build homes. An approach could be introduced into national building regulations, and may even be applicable to older properties after renovations have taken place.

Windows and doors can often be the part of the building envelope most susceptible to noise transmission. This means the ISO in development could have a real influence in guiding specifiers towards glazing and IGUs that have better noise control properties.

The classification scheme proposes six classes: class A being the highest and class F the lowest. For each class, limit values are given for airborne sound insulation (traffic sounds, speech and music), impact sound pressure level (footsteps, jumping and dropped objects), and noise from service equipment. 

A property that achieves the highest classification (A) would be expected to provide a high level of protection with help from advanced acoustic laminated glazing, which is appropriate for homes under flight paths or near music venues. 

Meanwhile, class B should provide good protection, under normal circumstances, without too much restriction to the behaviour of occupants, like an inner-city apartment. The lowest class (F) is described in the standard as offering no protection against intruding sounds, which could make the property fairly undesirable, unless it was in the countryside perhaps.

For buyers or renters, the classifications could add peace of mind that they are protected from noise pollution if, for example, they are looking at property on busy roads, near rail lines or in city centres. As such, the sound insulating properties of glass could add, or remove, a significant amount of value from the property as it influences its classification.

ISO 19488 would adopt two approaches to verifying compliance to ensure the desired classification is achieved in practice. One is based on field measurements only, whereas the second approach considers checks at three key stages: design, mid-construction and completion.

With building regulations on sound insulation (Approved Document E in England) being limited to transmission through walls, floors and stairs, it’s often up to the client to direct how sound attenuating they’d like the glazing to be.

Acoustic laminated glass, for example Pilkington Optiphon, will be key for specifiers to achieve a class A in sound insulation. Using a special PVB (polyvinylbutyral) interlayer, it works by reflecting sound back towards the source and absorbing sound energy within the glass. The Pilkington Optiphon range has been given the seal of approval by Quiet Mark, the international mark of approval from the Noise Abatement Society Charitable Foundation.

It can also be combined with other Pilkington products to provide multi-functional glazing solutions with additional features such as increased security, thermal insulation, solar control and even self-cleaning. 

However, specialist sound insulating glazing is not the only way specifiers and IGU manufacturers can achieve improved sound insulation. Thicker glass generally offers better sound insulation, and selecting panes of different thicknesses can maximise performance. The same rules apply for triple glazing but more care is needed in the selection of the glass types in order to optimise sound insulation.

Attention also has to be paid to the noise source, as glass performs differently against different types of noise. For example, a product effective at reducing road traffic noise transmission may not be effective against human speech (and vice versa).

Although still in development and subject to change, ISO 19488 should be under enquiry by the time you read this. If and when this standard is published, it could provide a framework for differentiation of one dwelling from another in terms of sound insulation.

We could see house buyers selecting where they choose to live on the basis of how quiet their new home will be, as well as its energy performance, proximity to schools, commute times, etc. Could quiet homes be making more noise in future?