In the twenty years I have been an acoustics consultant, I have lost count of the number of times I hear the field referred to as “the dark art”. For a ‘niche subject’, acoustics is surprisingly broad and spans several industries, with many acoustics consultants practising within just a few. If, however, we only focus on the built environment, there is still a lot to consider and, as a result, a lot that is misunderstood. These misunderstandings can lead to conflict, which, in some cases, can lead to litigation.
I recently investigated an acoustics failure within a very expensive fitout project, which is likely to cost over a million pounds to rectify, and a substantial amount (as yet to be determined) in loss of earnings due to the unusable spaces that have been built. While that might sound like an outlier, it might be helpful to think of your own home and work lives and how they are impacted by poor acoustics.
How much of the enjoyment of your home has to do with its separation from noise? This could be as simple as being able to sleep through the night (without the sounds from the pub down the road waking you up) or being able to relax on a Sunday afternoon without hearing your neighbours arguing. In more serious cases, it could be the simple assumption that the vibration from building work next door will not result in a crack in your wall.
Likewise, how much of your ability to be productive at work has to do with its separation from noise, but also the degree of confidentiality you are afforded by private rooms? You might be the head of HR and have a sneaking suspicion that your conversations are not confidential. In more expensive cases, it could be that your scientific laboratory, which houses sensitive equipment, is unable to operate due to the significant noise and vibration from mechanical services equipment on the floor above. In more potentially serious cases, it could be that you are unable to clearly hear a fire alarm or other warning signal in the building in which you work, which could have a tragic outcome.
Who is Responsible for Acoustics?
Wherever acoustic performance is important, be it a residential, industrial or commercial building, there will be at least one of four (or more) parties upon which the responsibility for the failure lies. Let us consider a simple fitout and the role of each party:
> The Client – who has an idea of what their dream building will achieve, often on a limited budget. If the client does consider acoustics, which they might not do until there is a problem, they could express their wishes in broad terms such as “sound proofing” and “dampening”.
> The Acoustics Consultant – our first point of real risk. Generally, the job of the consultant is to provide advice and specifications for the acoustic performance of the building. They are not infallible and can, on occasion, get it wrong.
> The Designer – in many cases, the designer must take that consultant’s report and, after translating it, implement the recommendations, some of which might be difficult to understand, into the building specifications. Here we have another point of risk.
> The Construction Team – this is the final point of risk. The builder might rely on the interpretation of the designer with regards to the acoustic specifications, however, they are often also reliant on the accuracy of the information provided by the manufacturers of building products, which, in turn, relies (in some cases) on the understanding of the manufacturer’s marketing team.
A Recent Case Study
A practice of audiologists (hearing scientists) secured an investment to open a new hearing centre. Within that centre, were several audiometric suites, which, as one might expect, must perform according to certain standards of sound insulation and reverberation (echo) management. The audiologists themselves, whilst familiar with acoustics terminology and concepts, had to rely on the designer to provide the correct specifications for audiometric suites. An acoustics consultant was hired to assist with the design and specifications, and a fitout company was engaged to build the suites.
Once the rooms were finished, the audiologists complained to the designer that they could hear sound from other parts of the building and also between rooms, rendering them unusable for testing. An investigation into such a matter would require a careful review of the client’s brief and the contract to establish whether or not the client communicated their requirements clearly. Terminology such as “soundproof” can be subjective and misleading. The second part of the investigation would be to establish how the client’s requirements were interpreted by the designer and acoustician, and to determine whether the design and specifications were capable of achieving them. Importantly, are there any limitations in the base-build that have been accounted for in the design? Finally, and normally through a process of acoustically and, potentially, destructively testing the spaces, the way in which the rooms were actually built must be investigated.
In my experience, a failure at each of the design processes described above can occur and does so fairly frequently. In some cases, mistakes can be rectified fairly easily. It might be a case of replacing plenum barriers located above partitions or simply correctly sealing service penetrations through acoustic walls. However, in acoustically critical spaces, the solution frequently requires complete demolition and reconstruction.
About the Author
Ros Lambert-Porter has 20 years of experience as an acoustics engineering consultant, with degrees in both audiology and acoustics. Ros has consulting experience in the United Kingdom, Africa and Australia and has had a varied career in different sectors from vibration monitoring in mining and the creation of hearing conservation programmes, through to environmental noise impact and building acoustics design. She is the managing director and technical lead of our Acoustics Consultancy team, which comprises expert acoustic and vibration engineers and consultants. The team provides a comprehensive suite of services across various sectors ranging from simple noise surveys and noise impact assessments to investigation of acoustic shock and complex building failure claims.
Ros is also an experienced speaker, having been a lecturer on the subject of acoustics, and is frequently called on to provide knowledge workshops and CPD presentations including ‘Debunking the myths of acoustic performance’, ‘Acoustics – what could possibly go wrong?’ and ‘Acoustic design for a neurodivergent workforce’.
If you have an acoustical related issue and need the services of our Acoustics Consultancy team, please contact us.
