Nuisance reverberation halved inside school dining hall
| Client: | Camelot Primary School |
| Location: | Peckham |
| Region: | London |
| Sector: | Education |
The acoustic environment inside the dining hall of Camelot Primary School in south London was transformed through the installation of Hush Absorber 50A panels.
Having been impressed with the ability of Hush Acoustics to effectively treat poor acoustic conditions within educational buildings in a previous project, the school’s executive headteacher approached the company to explore the potential for reducing noise levels in a number of areas.
The key room to address, given how busy it can be at lunch and break times, was the dining hall. The high ceilings which feature in the hall create a large volume and it is typically built and decorated with materials that result in many hard surfaces. While these surfaces are highly durable and low maintenance, they can contribute to poor acoustic conditions.
The dining hall had become excessively noisy and echoey at peak times, with a significant build-up of background noise resulting from sound reverberation. This is caused when sound waves are
reflected off hard surfaces back into the room, meaning that sounds generated through routine use, such as talking, music playing and furniture being moved, become unbearably loud.
MEETING THE CHALLENGE
Hush Acoustics was tasked to provide a solution to the reverberation and echoing problem. The company worked with executive headteacher James Robinson and the school trust previously to successfully address a similar issue at its nearby Cobourg Primary School in 2018 with outstanding results.
Step one was for Hush Acoustics to conduct a site survey to gather the information needed for the reverberation calculations in areas of concern. Whilst the survey concentrated on the dining hall, the team was also asked to assess another school hall and four classrooms which were regarded as being very poor acoustically with a view to improving these in future.
The survey gathered information on material finishes within the room and the size of the areas as well as providing an opportunity to explore the possible positioning of the panels. The Hush team was then able to feed this information into its calculation software to arrive at the best possible reduction in reverberation.
THE SOLUTION
24x Hush Absorber 50A panels were mounted to the existing soffit because of the limited space available on the walls, where sound absorber panels are often positioned. The 1200 x 1200mm panels, which feature a 50mm thick acoustic foam and supporting brackets, were installed symmetrically within the bays that formed the ceiling and finished in an outer fabric colour that is consistent with the rest of the room.
In terms of the acoustic improvements that could be achieved given the building design and usage, the installation of the absorber panels sought to reduce reverberation by half. The initial acoustic survey estimated that the dining room’s overall mid-frequency reverberation time (T mf ) was 6.01 seconds, but after the Hush Absorber 50A panels were fitted, this was cut to 2.97 seconds.
Installation was completed during the school holidays by Hush Acoustics to avoid any disruption to the day-to-day operation of the school.
Robert Crampton, Managing Director of Hush Acoustics said:
“As is the case with many older school buildings, some of the rooms within Camelot Primary School are not ideal from an acoustic perspective, but through the installation of high-quality absorber panels we can make a huge difference, as we’ve seen here.
“Whilst BB93 rightly stipulates a very low mid-frequency reverberation time (T mf ) of 0.4-0.8 seconds for optimum speech intelligibility, this is not always achievable in retrofit projects because of the amount of space available to mount absorber panels. This is why having a solution like Hush Absorber 50A that is ceiling mounted, can be extremely useful in rooms such as the dining hall at
Camelot.”
