Services/Acoustics and Noise
Noise Assessments
Identifying noise impact and site suitability, drawing from our multi-disciplinary expertise.
We measure the site’s noise conditions and review its viability for natural ventilation. We also establish the criteria for external MEP plant to limit the impact of the development on neighbouring properties. By utilising our expertise in ventilation and overheating, the strategies are coordinated from the start.
Winner
CIBSE Building Performance Consultancy of the Year2022, 2023, 2024, 2025, 2026
Noise conditions have environmental consequences beyond the ventilation strategy.
A noise assessment for planning covers three things. What the site is already exposed to, measured rather than estimated, whether that comes from a road, a railway, a flight path or an industrial neighbour. Whether the homes inside the scheme will meet the internal levels planning authorities expect, which come from BS 8233 and the professional practice guidance built on it. And where the development is itself a source, whether its plant is acceptable against the background, which is rated under BS 4142.
Meeting internal noise levels on a noisy site usually means windows cannot be relied on for ventilation. As a result, overheating criteria can be more challenging to comply with. This is a scenario where two environmental comfort standards drive conflicting solutions, and the reconciliation may require acoustic ventilators, mechanical ventilation with attenuation, deeper reveals, winter gardens, or layout changes.
XCO2 can carry out both assessments. By coordinating both drivers, we ensure solutions are robust and compliant. This often means quicker turnaround of the assessments and lower planning risks.
What we do
Scope is set around the site, its sources and the stage the design has reached. Most commissions combine several of the following.
Noise impact assessment for planning
Environmental noise surveys
Internal noise criteria for habitable rooms
External amenity space noise levels
Facade and glazing performance requirements
Plant noise rating against background
Acoustic ventilation strategy
Noise and overheating reconciliation
Building services noise and vibration
Noise chapters within an EIA
Planning condition and objection response
At Lexden Road the overheating analysis explicitly took the site’s environmental noise constraints into account, alongside air quality, health, wind and pedestrian comfort, on a scheme committed to Passivhaus. West Green Place carried the same environmental scope across Pocket Living’s largest development. Images Karakusevic Carson Architects and Pocket Living.
How we work
01
Baseline survey
The existing noise climate measured on site across day and night periods, long enough to characterise the sources that actually matter rather than the ones that happened to be there.
02
Criteria and exposure
Internal levels for habitable rooms and external levels for amenity space set against the applicable guidance, and the facade performance needed to reach them established room by room.
03
The ventilation trade
The acoustic requirement tested against the overheating and ventilation strategy, so the glazing, the openings and the plant are specified once rather than argued between two consultants.
04
Plant and reporting
Where the scheme is a source, its own plant rated against the measured background, with mitigation and a report written for the environmental health officer who will read it.
Where we work
01Residential and estate regeneration
02Mixed use
03Cultural and performance venues
04Healthcare
05Workplace
06Masterplanning
Selected projects
Schemes where noise set the constraint
Carpenters Estate
The masterplan for a 9.3ha public housing neighbourhood beside the Queen Elizabeth Olympic Park, replacing 710 homes with around 2,500 across fifteen plots. XCO2 provides M and E and environmental services at masterplan level and on individual phases, including acoustics and noise.
Around 2,500 homes, 50% affordable
Ledbury Estate
The redevelopment of a 1960s estate in Peckham, providing 224 council homes for existing residents and 116 mixed tenure homes alongside a community hall and commercial space. XCO2 provides M and E and environmental planning consultancy, including the noise impact assessment.
Planning granted, June 2022
Selby Urban Village
A former secondary school and underused playing fields transformed into a neighbourhood centred on a new Selby Centre community hub. XCO2 provides M and E and environmental consultancy, with acoustics and noise assessed alongside overheating, air quality and wind.
202 council homes for rent
Works with
Common questions
What is a noise impact assessment?
A study submitted with a planning application setting out the noise a development will be exposed to, whether its occupants will be adequately protected from it, and whether the development itself will disturb anyone nearby. It starts from measurement on the site rather than from published data, because the sources that matter are local and the difference between a road at fifty metres and a road at twenty is the whole answer.
Does my application need one?
Usually where residential development is proposed near a transport corridor, a commercial or industrial neighbour or a venue, and generally where the scheme introduces plant close to existing homes. Most authorities set this out in their local validation requirements, and where noise is likely to be contentious the scope is worth agreeing before the survey rather than after the objection.
What is BS 8233?
It is the British Standard giving guidance on sound insulation and noise reduction for buildings, and it is the source of the internal noise level guidelines that planning authorities apply to habitable rooms, separately for daytime and night time, along with guidance for external amenity areas. It is guidance rather than regulation, which is why the reasoning in the report matters as much as the numbers.
What is BS 4142?
The standard for rating and assessing sound of an industrial or commercial nature. It compares the rated level of a specific source, typically plant, against the measured background sound level, with corrections for character such as tonality or intermittency. It is the method used when a development’s own equipment has to be shown to be acceptable to its neighbours, and it is the assessment that most often produces a plant selection or attenuation requirement.
How do noise and overheating conflict?
Directly. Internal noise levels on an exposed site are usually met with the windows closed, and overheating criteria are usually met by opening them. Assessed separately by two consultants, the scheme can satisfy each in isolation and still be undeliverable. Resolved together, the answer is a specification: which rooms can ventilate naturally, which need acoustic ventilators or mechanical ventilation with attenuation, and whether the layout should put habitable rooms on the quieter facade instead.
Is this the same as a workplace noise assessment?
No, and the two are often confused because they share a name. Occupational noise assessment concerns employee exposure and hearing protection under health and safety legislation. This service is environmental and building acoustics: the noise a development is exposed to, the noise it creates, and the design that reconciles them. Different standards, different regulator, different specialists.
What about sound insulation testing?
We do not do sound insulation testing. Pre-completion sound insulation testing between dwellings is a separate, accredited discipline carried out on site once the building is up. Our work is the design stage: establishing what the facades and separating construction have to achieve, and specifying the ventilation and plant that follow from it. Where testing is required we coordinate with the tester rather than replacing them.
Where do you work?
We are based in London and work across the UK, with a second office serving projects in Singapore and the wider Asia Pacific region. Contact us to discuss a scheme.