Acoustics, Noise and Vibrations

Every building is different and we provide the acoustics services for all of them, including very special spaces such as schools, laboratories, theatres or historic structures as well as complex hospital buildings that require careful, strategic design to address the acoustics in a multitude of different spaces and functions.

Trends evolve, such as the increasing use of timber, and we embrace changes and innovate accordingly. For example, the move towards open plan offices and space use flexibility in commercial buildings, have made acoustics more important in employee satisfaction. In healthcare facilities, while the link between sleep quality and recovery is evident, confidentiality in wards and patient rooms also needs to be taken into account. We often use sound masking systems to artificially raise ambient noise level within a space (white noise). It provides the benefit of speech privacy while reducing sleep disturbance.

We have provided acoustical design for numerous tall buildings around the world and are experienced in developing different solutions for a building when its structure changes from concrete to steel. Our specialists advise on what sound insulation is required between a mixed-use scheme’s different functions, such as retail, leisure, offices and residential apartments, and how to control noise and vibration from entire floors of mechanical and electrical plant to highly noise-sensitive spaces directly adjacent.

Our rich portfolio includes commercial buildings such as Salesforce Tower in San Francisco, The Shard in London and 720 Bourke Street in Melbourne, cultural buildings like Dubai Opera and Zayed National Museum in Abu Dhabi. For the latter, we carried a complex 3D acoustic modelling to assess transmission of noise between spaces as well as to enhance acoustic for presentation and performance.

We have also worked on transport terminals including London Bridge Station, hospitals such as Alder Hey Children Health Park in Liverpool and Sahlgrenska University Hospital in Gothenburg. Our work in the hospitality sector includes hotels such us Primus Hotel in Sydney and Park Hyatt in Auckland, where we placed reverberation control treatments to ensure noise from function rooms would not impact guests.

ROOM ACOUSTIC MODELLING

We use bespoke 3D acoustic modelling to enable our clients and design teams to hear, or ‘auralize’, the acoustics of a space long before designs are finalized and the building has been constructed.  This enables fine-tuning the sound characteristics of a building’s spaces and means we can influence the layout and the materials used from the outset. It saves time and prevents expensive remedial treatments after projects are completed. An example is The Place, a commercial building in London, where we used auralization for the foyer to demonstrate sound insulation between meeting rooms.

Our teams advise contractors and architects on building layouts to minimize the need for expensive acoustics countermeasures, or retroactive sound insulation between rooms. We use detailed 3D room acoustics computer modelling to test different options and evaluate which enables speech privacy and intelligibility.

 

ACOUSTIC DESIGN FOR PAVA SYSTEMS

The Public Address and Voice Alarm (PAVA) refers to the ability to clearly hear and understand announcements over public address and voice alarm system. From retail malls and commercial buildings to cultural buildings and airports, we ensure the effectiveness of this system through the compliance of quantitative speech intelligibility. This involves studies to assess the ease of understanding announcements, appropriate choice and placement of loudspeakers and calculations to work out delays between the loudspeakers. With the rise of security measures in every type of building, the importance of good PAVA systems is non negligible. For instance, in an emergency situation, people will react in a more structured way if they hear correctly the announcements.

 

BUILDING SERVICES NOISE CONTROL

Our acousticians can assess mechanical and electrical building services with respect to both internal and external noise breakout. We design in extra measures to protect user comfort. These include traditional air conditioning system attenuators, plant vibration isolators, rooftop acoustic screens, and occasionally something more innovative such as quiet and sustainable ground water cooling systems as opposed to noisy mechanical chiller plants. We are constantly developing new ways to reduce the noise from building services equipment such as chillers, generators and combined heat and power (CHP) plants.

VIBRATION STUDIES

Many buildings are located beside or above sources of potentially significant vibration, such as railways, leading to concerns about the transmission of vibration and structure-borne noise into acoustically-sensitive spaces. We conduct specialist studies to assess the impacts of vibrations on a building, including tactile vibration and re-radiated noise.

Vibration from underground railways often manifests itself within buildings not as tactile vibration (vibration you can feel) but as low frequency re-radiated noise, perceived as a low rumble as a train passes along the line.

Our detailed vibration studies address these concerns, while our experience ensures we recommend the right solutions for our clients. Techniques such as using room finishes and treatments to reduce re-radiated noise, enable us to limit the need for whole-building insulation to only situations where vibration impacts are high and cannot be mitigated by other means. In these cases, we advise architects and developers on when and how to install the complex vibration isolation systems.

 

CONSTRUCTION NOISE MANAGEMENT

Construction noise management involves not only the outdoor aspects of noise in the area surrounding a construction site, but also its impact on and within local buildings. We develop noise and vibration control plans to enable contractors and project managers to know ahead of time where problems are likely to occur and what kind of mitigation would be appropriate to proactively implement. We also perform noise and vibration monitoring and oversee contractor compliance on larger construction projects.

 

COMMISSIONING TESTING

Commissioning testing is the analysis of ambient noise levels, reverberation time, airborne and impact sound insulation, speech transmission index and plant noise emissions. Our acoustics testers are registered on the Association of Noise Consultants scheme in accordance with building regulations and BREEAM.

We also evaluate already constructed buildings and provide insights to the owner on how to improve the acoustics.

We offer in-depth expertise in all aspects of environmental acoustic services, from baseline noise level monitoring and the development of noise models, to monitoring programmes in support of environmental impact assessments. State-of-the-art equipment, coupled with strategic modelling and risk assessment techniques, enable us to evaluate problems accurately and engineer workable solutions to complex and potentially costly environmental issues.

Our core environmental acoustics management services include:

• Acoustic impact assessments

• Baseline noise level assessments

• Best practical available technology assessment

• Noise source inventories

• Noise source monitoring – point, line and area

• Predictive acoustic modelling

• Quantitative health risk assessments for hazardous noise levels

• Vehicle noise monitoring

 

INSTRUMENTATION AND MONITORING

We have installed and monitored geotechnical ground and building monitoring systems associated with shored excavations, tunnels, dams, dewatering projects, and for slope stability. Our clients include large-scale general contractors, governments, transit and transportation organizations as well as major energy companies.

• Vibration and Ground Movement Monitoring

• Remote and Real Time Monitoring

• Shoring Monitoring

• Building/Structure Deformation Monitoring (Movement, Tilt, Strain, Load, Pressure)

• Underwater surveillance for marine infrastructure

 

NOISE AND ACOUSTICS

Our experience includes noise exposure forecasts, noise level surveys, regulatory compliance, noise source identification and noise reduction proposals.

• Noise level surveys (compliance studies)

• Construction surveillance

• Regulatory and Community noise impact studies

• Source identification and noise reduction recommendations

• Exposure forecasts using computerized simulations

• Noise reduction implementation, including turnkey projects

 

INDUSTRIAL NOISE

Our team also contributes to project management with a view to implementing corrective measures to reduce noise in industrial areas.

• Workplace noise studies, including sound measurement and employee dosimetry

• Evaluation of exposure to hand/arm vibrations and whole-body vibrations

• Acoustical imaging

• Establishment of noise control programs and Corrective noise reduction measures

• Turnkey projects for implementing noise/vibration controls

• Noise level specifications for equipment purchases

• Acoustic design for new facilities (noise mitigation)

• Employee noise exposure surveillance program

 

MARINE ACOUSTIC MONITORING

Working with our Maritime and Natural Environment and Ecology teams, we offer specialist marine acoustics services, including:

• Baseline underwater noise measurement and noise rating curves analysis

• Real-time monitoring and spatial location of marine mammals

• Determination of underwater sound levels emitted by different types of machinery: power hammer, pneumatic drill, vibratory hammer, hydraulic excavator, ships, ferries, dredger, etc.

 

VIBRATION

• Real-time vibration monitoring (construction site)

• Mitigation measures elaboration for constructions close to railways or shutting yards

• Mechanical equipment isolation (isolator isolation, inertia base design)

• Blasting monitoring and optimization (vibration, flyrock and overpressure)