Acoustic Standards in Building Regulations: Why Minimum Isn’t Enough

How do you achieve acoustic performance in walls and floors that is better than the minimum standards in the Building Regulations, and why is it necessary?
Providing good acoustic insulation in homes and non-domestic buildings often means going beyond the minimum standards. There are a number of reasons why this could be the case in both new build and refurbishment projects, but one clear trend in Hush Acoustics’ experience is that there is increasing interest amongst developers, property owners and architects to deliver improved sound insulation.

Given the numerous possible construction materials used to create walls and floors, there is no single solution that can be deployed to improve acoustic performance above compliance. Take, for example, a project where an additional 10 dB sound reduction above the minimum airborne level is required in a 1930s-era timber joisted floor. The approach you would adopt here would be very different to what it would be for a building featuring masonry floor construction.

However, the good news is that the range of acoustic products now available means a higher performing, bespoke acoustic design is almost always achievable. Going better should no longer be regarded as aspirational and restricted only to bigger budget or high-end projects – it can actually be incorporated into the specification of mainstream projects without adding significant cost or complexity.

Minimum performance levels are lagging behind

Unfortunately, raising the minimum acoustic standards for the UK’s built environment in our Building Regulations has been a low priority for policymakers in recent decades whose focus has very much been on higher thermal performance, fire safety, sustainability and more recently, ventilation.

As a result, we have not seen a significant upgrade to Approved Document E, the Building Regulations applicable to England & Wales relating to the passage of sound in buildings, since 2003.

Over that 20+ year period, the quality and performance of acoustic insulation products, coupled with innovative approaches to combining them to create acoustic systems, has improved massively. This has resulted in a mismatch between what the Building Regulations stipulate as a minimum – and, therefore, deem acceptable – and what is actually achievable.

To put the lack of progress on the acoustic regulations into perspective, in 2003, the thermal insulation required in external walls by UK Building Regulations was typically a minimum U-value of around 0.35 W/m²K. Today, that has dropped significantly for new builds to 0.18 W/m²K, helping to facilitate the construction of much more energy efficient homes versus those built in the early 2000s.

This illustrates a missed opportunity. If the minimum acoustic standards in Approved Document E had been increased at regular reviews over the last 20 years, the vast majority of homes being built today would be much better insulated against noise.

Many architects and developers recognise this, hence why they are seeking better performance by setting their own performance targets.

Meeting application-specific acoustic targets

One of the most common reasons why a higher performance over the Building Regs minimum is required is where a residential unit is connected to commercial premises. This could be, for example, flats created in a conversion project above a shop, bar, office or restaurant.

Here, the purpose and use of the commercial premises may determine if additional sound reduction measures will be required in the separating floor and walls. The levels could even be stipulated by local authority officers as a condition for planning consent.

Take the example of an office on the ground floor with a flat above. Noise will be generated in the office typically from people talking in-person and on their phones, computers being used, furniture being moved and office equipment like printers operating.

It may not be 24/7 noise, but due to the presence of numerous people at any one time, relatively high noise levels could be generated. In this example, a 5-10 dB increase above the Building Regs minimum may suffice for the separating floor to reduce the potential for excessive noise being heard in the flat above.

If the same flat were located above a bar where live music was being performed regularly, that 5-10 dB improvement is likely to be ineffective given how much louder the sound would be. An additional reduction of 10-20 dB may be needed here.

However, these are only illustrative figures – the exact uplift in acoustic performance needed in dB will depend on the project. This is why an acoustics specialist like Hush should be consulted to achieve the best results for the budget available.

The difference in the level of sound reduction offered will usually be due to the amount of mass it contains and the performance of the decoupling elements such as resilient bars. In general, the more mass you add to the floor construction by incorporating dense materials like cement particleboard acoustic floor panels and Soundbloc plasterboards, as well as mineral wool slabs where voids are present, as in timber joisted floors, the greater level of sound reduction can be achieved.

Improving acoustic insulation to create healthier homes

Another major driver for going beyond the minimum acoustic standards is to offer improved health and wellbeing for residents or building users.

The need to create homes and non-domestic buildings that are well insulated against unwanted sound is becoming increasingly important as our understanding of the link between poor acoustic control and ill health deepens. Rather than noise being regarded simply as a nuisance, many studies published over the last three decades suggest it is much more dangerous.

In the recent European Environment Agency (EEA) ‘Environmental noise in Europe 2025’ report, researchers declared that over 110 million people, equivalent to more than 20% of Europeans, are exposed to high levels of noise that harms our health, the environment and the economy. Whilst the study largely focused on noise from traffic, what is most notable is the evidence it found on long-term exposure to noise being linked to negative health impacts including cardiovascular diseases, mental illness, diabetes and even premature death, with children and adolescents being particularly vulnerable.

In time, we may see new minimum acoustic insulation standards being set to ensure our homes are not damaging to our health, but in the meantime forward-thinking developers are taking the initiative. And the social housing sector is taking the lead here, often developing a specification for separating floors and walls that goes beyond the minimum levels to lessen the risk of noise complaints and neighbour disputes resulting from anti-social behaviour.

Highly marketable benefits

Better acoustics can also be a powerful selling point in the residential market. New build and conversion properties which are better insulated against noise may have a competitive advantage in the open market compared to those built to compliance levels.

The prospect of being protected from the sounds generated in neighbouring properties and external sources is appealing to many homebuyers and tenants. While the trend of working from home that emerged during the pandemic has declined recently, the way we use our homes today is still very different to how we did in the early 2000s.

Hence why additional sound insulation is advantageous in domestic properties where noise generated by home gyms, cinema rooms and home offices is more effectively controlled to prevent being a nuisance to neighbours or even within the same property.

The same competitive edge may also apply to hotels, HMOs (houses of multiple occupancy) and student accommodation, including PBSA (purpose-built student accommodation) buildings. In these types of buildings, taking the acoustic performance of the separating walls and floors to a much higher level provides marketable benefits in respect of being able to offer rooms with ‘excellent soundproofing’.

Meeting higher sustainability ratings in Scotland

Higher acoustic standards are also often incorporated into the definition of more sustainable homes, particularly in Scotland.

The Scottish equivalent of Approved Document E, Section 5.0 Noise of the Scottish Building Standards, already sets minimum performance standards that are higher than in the rest of the UK – you can read more on this here. However, there is an additional section within the Technical Standards which aims to encourage clients, developers and architects to create more sustainable homes which also raises the bar on acoustic performance.

This takes the form of Silver and Gold sustainability standards under Section 7.0 Sustainability. A key feature of this is “quality of life”, and considerations around creating homes that can accommodate more flexible living, working and studying patterns. Importantly, these standards seek to offer protection from noise from adjacent buildings to higher levels than those published in Section 5.0 in recognition that more peaceful homes contribute to better health outcomes.

For example, the compliance acoustic performance in Scotland for airborne sound in the separating wall of a new build home is ≥ 56 dB (DnT,w). To achieve the Silver sustainability standard, an improvement of 2 dB is required, and for Gold standard the wall would need to achieve ≥ 60 dB (DnT,w) – both of which would need enhanced acoustic designs.

Supporting developers who are setting their own higher standards

Hush Acoustics provides specialist technical advice to architects and developers on how to improve the acoustic performance of walls and floors beyond the minimum standards set by the Building Regulations.

Our range of acoustic products spans everything from high mass acoustic floor panels, multi-purpose boards and resilient bars to rubber membranes, sound absorber slabs and acoustic battens. This, coupled with the extensive experience and technical knowledge of the Hush team, ensures that a solution can be developed to meet any building sound reduction challenge.