dBx Acoustics

Acoustic Design and the WELL Building Standard

Various environmental characteristics can have direct impacts on mental health and well-being, such as housing, crowding, noise, indoor air quality, and light

The WELL Building Standard, originally introduced in the US, is steadily gaining importance in the design of UK office buildings. The intent of this performance-based standard is to produce workplaces which have a positive impact on human behaviours related to health and wellbeing. The standard covers things you would expect, such as air quality, light and of course acoustics. However, it also requires designers and occupiers to consider the nutrition, fitness and cognitive and emotional health of building occupants.

What’s the point?

At first glance, aiming for WELL standard (whether formally accredited or not) might seem off-puttingly costly. It’s important to remember that the biggest cost to any business is its people. Therefore, anything done to reduce sickness, improve productivity and enhance workplace satisfaction actually becomes a crucial investment. If you’re a regular reader of our blog, you’ll know that we firmly believe that an investment in acoustic design will quickly pay for itself – studies have shown that distracting noise can contribute up to a 66% decline in performance on office related tasks. If you add in the effect of other environmental factors, the quality of our working environment is evidently crucial to our individual and corporate success.

WELL Building Standard Features – Acoustics

The standard consists of a number of ‘features’ (rather than credits) against which we can assess buildings. This includes a thorough consideration of acoustic items under the following six headings. You can access the full information on each feature here.

Exterior Noise Intrusion (Feature 74)

This one is an ‘easy win’ for UK office design, with a less stringent criterion than that recommended by the BCO Guide to Specification 2014 and BS 8233:2014. We’d continue to recommend that reducing exterior noise intrusion (e.g. traffic noise, plant noise) in line with current design standards is best practice. dBx Acoustics can help you here, by carrying out environmental noise surveys and acoustic modelling for new buildings to advise on facade requirements and ventilation strategy. For existing buildings, we can carry out a noise survey to establish what current noise intrusion levels are.

Internally Generated Noise (Feature 75)

Something we love about this two-stage feature is the requirement to begin with an acoustic planning exercise to identify loud and quiet zones, and noisy equipment. This information allows us to design the space intelligently to minimise disturbance and distraction. Once again, we would recommend carefully considering this when planning any work space. Not only will this help with space planning, it will enable early integration of the acoustic features suggested in Feature 80 and Feature 81. Allowing for intelligent value engineering of the acoustic design.

This feature also covers the control of noise from building services, both in the system design and in ensuring best practice in installation to minimise noise issues. dBx Acoustics can not only help specify noise limits for individual plant items; we can calculate requirements for silencers and crosstalk attenuators, predict the risk of regenerated noise within the system, and advise on maximum duct velocities to help keep regenerated noise under control.

There are also criteria for noise within schools, which are in conflict with the current UK best practice set out in Building Bulletin 93, and for ‘disruptive music’, which may be in conflict with the requirements of Local Planning Authorities. In both instances, we would advise clients to meet their statutory obligations. Which, in the majority of cases, will provide a better condition than the WELL Building Standard.

Reverberation Time (Feature 78)

Reverberation time is, in essence, how ‘echoey’ a space is. You can learn more about this in our Jargon Buster article. WELL sets relatively stringent criteria for conference rooms and open plan office spaces which are appropriate to ensure that noise build-up is controlled, and that colleagues can comfortably communicate. Reverberation time is controlled by the use of ‘sound reducing surfaces,’ addressed in Feature 80 of the Standard.

Sound Masking (Feature 79)

We use sound masking systems to artificially introduce broadband noise into the workplace. The intent of this is to raise the background noise level to provide some speech privacy across the floorplate, without the noise itself being distracting in nature. Our experience is that such systems are common in the US. Typically they are only used in the UK where the ‘natural’ background noise is too low. These systems can be costly and we’d therefore recommend using building services and a level of controlled noise intrusion to provide this sound masking organically wherever possible. Fortunately, this is considered an ‘optimisation’ by WELL rather than a precondition of awarding certification.

Sound Reducing Surfaces (Feature 80)

We have to admit, this feature seems somewhat redundant when considered against Feature 78 (reverberation time). Both features are ‘optimisations’ and perhaps the intent is to allow designers to take an either-or approach (or to be able to achieve this feature without the aid of an acoustic consultant!). This feature recommends minimum acoustic absorption performance and percentage areas for wall, ceiling and floor finishes. This will have the effect of controlling reverberation time throughout the space.

Sound Barriers (Feature 81)

Finally, another ‘optimisation’ feature offers best practice and some design guidance for acoustic separation between spaces, and for the acoustic specification of doors and walls. Most aspects of this feature should already be considered in a good office acoustic design and recommendations are provided by BCO and BS 8233:2014. Residential acoustic privacy is already covered in the UK by Approved Document E of the Building Regulations, with a requirement for pre-completion acoustic testing.

On average, employees lose 80 minutes each working day due to distractions

Feeling Better?

Overall, we’d like to see the WELL Building Standard take off in the UK. The holistic design of buildings to make our lives better should surely be the intent of all designers. A framework to work against can only be a good thing. Some aspects of the standard are contradictory and may need some refinement. It would be good to see a UK version for the UK based on our existing standards and best practice which in many cases exceed the US requirements. This shouldn’t take away from the effort to create a better, more pro