Leading UK acoustic products manufacturer Hush Acoustics has provided a highly effective reverberation and echo reducing solution to transform a particularly noisy school hall into a comfortable multi-purpose environment, offering the optimum balance of performance and cost.

The hall at Sandy Lane Primary School in Bradford had become an extremely noisy environment due to how it is used today versus its original purpose, and the number of children who are likely to be using the space at a given time. The school is a large educational facility with a capacity of over 300 boys and girls aged 4-11, as well as a nursery for 2-4 year olds, which has grown significantly from the small Victorian school founded 130 years ago.

The school hall is extensively used as a dining room, for assemblies, physical education sessions and other communal learning activities. This meant it was affected by a very common acoustic issue in spaces of this kind, reverberation and echo, which occurs when a high level of sound is generated in rooms where many hard surfaces are present. In the case of the Sandy Lane hall, this included painted masonry walls, a lino floor, an exposed soffit and six large glazed panels.

Long-running noise issue, swiftly resolved

Keen to resolve the issue within the shortest possible timeframe, a high priority for the school was to find an acoustics specialist capable of responding quickly and completing the work without disruption to day-to-day school operations. Hush Acoustics were able to accommodate these demands with ease, given the company’s experience of working on numerous other similar school projects across the UK involving reverberation.

Reverberation is the phenomenon of soundwaves, generated by everyday activities such as talking, music, sporting activities and furniture being moved, bouncing off surfaces back into a room, rather than being absorbed as they would be by softer materials like carpets and fabric curtains. This causes a cacophony in the room, creating an often unbearably high level of noise that contributes to teachers feeling exhausted and children disengaging from learning and social activities as a result of poor speech intelligibility.

Hush Acoustics were approached by the school to propose a solution for the 12.2m wide x 11.8m long x 6.9m high hall, along with two other suppliers. The process began with an initial site visit that enabled Hush to properly assess the space, identify any physical or operational constraints and gather all the relevant data.

From this, the Hush technical team were able to carry out the necessary acoustic calculations to generate a detailed report. This offered three options for reducing reverberation and echo according to the budget and level of noise control required.

Targeting a two-thirds reduction in reverberation time

The initial assessment revealed that the school hall’s reverberation time (RT) – the time it takes for sound to decay by 60 decibels (dB) in a space after the source stops – was 4.97 seconds. Some frequencies even showed spikes exceeding 7.0 seconds, highlighting the severity of the acoustic issue.

These existing levels were significantly higher than those stated in the design guidance for schools in England & Wales, BB93 (Building Bulletin 93), which stipulates an RT of between 1.5s and 2.0s in indoor spaces of this type.

The solution agreed with Sandy Lane was to install 52 x Hush Absorber 50 sound absorption panels within the space to provide 75 sq. m of absorption that did not previously exist. The proposal was to install the 1200mm x 1200mm panels on the soffit within the existing bays created by the ceiling beams and on selected wall locations.
Prior to the installation work commencing, the Hush team revisited the school to discuss layout in detail, the colour and logistics for completing the project, which was handled fully in-house.

Hush Absorber 50 panels are formed using a specialist acoustic foam core wrapped in a high quality interior fabric available in numerous colours. At Sandy Lane, a light grey colour called Chrome was selected to complement the existing décor.

Installation was completed in just one day during the school holidays to prevent term-time disruption, utilising a scaffold tower to access the soffit areas which could be repositioned as the work progressed. This was an additional challenge for the installation team, given that the soffit was up to 6.8m above the floor level.

An instant acoustic transformation

The installation of the Hush Absorber 50 panels instantly reduced the RT by almost two-thirds, bringing the internal environment in line with the BB93 guidance. The school hall is now calculated have an average RT of just 1.87s.

Commenting on the success of the project, Stephen Wood, caretaker at Sandy Lane Primary School, said:

“Given the severity of this noise issue that had developed, the Head of the school wanted to install an acoustic treatment in the hall as a matter of urgency to allow for the space to be used more effectively by pupils and staff. Hush provided the most competitive price for the acoustic solution, allowing for the greatest number of panels to be placed into the space within our budget. This, combined with their technical expertise, was the key reason why Hush were appointed.”

Robert Crampton, Managing Director of Hush Acoustics, added:

“We were delighted to be appointed to help resolve the severe reverberation and echo issues experienced at the Sandy Lane Primary School hall. It is a common problem in schools and one that we are highly experienced in resolving with maximum efficiency – a factor that means we can usually provide a solution at a more competitive cost and more quickly than other suppliers.”

Find out more about Hush Absorber 50 absorber panels and all the acoustic products and systems available from Hush Acoustics at https://www.hushacoustics.co.uk/