Background
In February 2024, Neilcott Construction Ltd commissioned Anderson Acoustics to review the acoustic design for the refurbishment of Churchill Court, an office building in Bromley which will house the Civic Offices for the London Borough.
The project involved internal CATB fit out works including a refurbished main reception, a secondary reception serving its residents, a new democratic hub with committee rooms, council chambers, and a mayoral suite, as well as external landscaping works and the introduction of updated mechanical and electrical plant.
What we did
Brought on at RIBA Stage 4, our review focused on ensuring the project met the acoustic performance criteria set out by Mach Group and that it complied with the relevant acoustic standards and guidelines.
Key Areas of Focus
Our review addressed several critical areas:
- Internal Airborne Sound Insulation: Ensuring walls and floors effectively block sound transmission.
- Impact Sound Control: Minimizing noise from footsteps between floors.
- Reverberation Control: Managing sound reflections in sensitive spaces and circulation areas.
- Building Services System Noise: Controlling noise from mechanical systems in noise-sensitive areas.
Design Risks and Mitigations
Several design risks were identified, along with proposed mitigation measures including for:
- Partitions with Glazing: Glazed screens may not match the acoustic performance of partitions. Mitigation involves specifying appropriate acoustic ratings for doors and glazed screens.
- Partitions with Doors: Doors can significantly reduce partition performance. Using high-performance doorsets or lobbied doors can mitigate this issue.
- Reverberation Times: Changes in ceiling materials may affect reverberation. Additional absorption areas were recommended.
Design Opportunities
Opportunities to enhance the acoustic design were also identified:
- Council Chamber Acoustics: Reducing reverberation time to improve speech transmission and aid communication during video conferencing.
Commissioning Testing
We have recently undertaken a programme of pre-completion sound insulation testing to determine the resultant sound insulation performance of partitions, as well as the internal ambient noise levels and reverberation times in rooms across the redevelopment.
The measurements on site indicate that the reverberation time criteria have been achieved in all spaces. Therefore, the associated BREEAM credits can be awarded.
Result
By addressing design risks and identifying opportunities for improvement, our acoustic design strategy aimed to create a comfortable and acoustically optimized environment for its occupants.
Project Progress
The project won South Project of the year at the Procure Partnerships Framework National Project Excellence Awards in September 2024, congratulations to the Neilcott Fit Out team. Read more about the project on Neilcott’s website here and on the London Borough of Bromley’s website here
Testimonial
“I would like to thank all the staff and contractors who have worked tirelessly to deliver the new Chamber on time and to support the transition of staff to the new building. This has been a very complex task.” Mayor of Bromley, Councillor David Jefferys
