Background
South Hampstead High School, part of Girls’ Day School Trust (GDST), refurbished two distinct spaces: a basement conversion into a modern wellness studio with a fitness gym and activity studio alongside changing rooms, and the transformation of an existing rooftop terrace into a sanctuary for outdoor learning, socialising and relaxation.
The school commissioned the refurbishments to provide their pupils with room to breathe, move, reflect and connect – essential foundations for both academic success and personal wellbeing.
Walters & Cohen Architects appointed Anderson Acoustics to provide acoustic design advice at RIBA Stage 4, working alongside the wider project team to help the scheme meet the suitable acoustic conditions as required under the Independent School Standards, referencing Building Bulletin 93 (BB93) and other design guidance.
The challenge
In the basement, the wellbeing hub sits close to existing mechanical plant and beneath a busy circulation corridor. Gym activity needed to be controlled so it wouldn’t transmit sound through the structure to other parts of the school, and the mechanical ventilation strategy needed careful review, as the airspeeds of the diffusers serving the gym would exceed BB93’s standard noise criterion.
The roof terrace space sits above existing art classrooms and is exposed to road traffic from College Crescent and further main roads, aircraft noise, and noise from existing rooftop plant, including a kitchen exhaust. The terrace includes a new teaching wall and canopy which needed to work acoustically as well as architecturally, creating an opportunity for the canopy to act as a screen to reduce plant noise.
What we did
We began with a site visit, carrying out a short-term attended noise survey to benchmark existing conditions on the terrace and in the basement, including measurements with and without the kitchen exhaust and mechanical plant running. This gave us a reliable picture of the existing sound environment to design against.
For the wellbeing hub, we proposed an alternative performance standard for ambient noise level in the gym space, with reference to CIBSE Guide A, with the supporting technical justification set out for the school’s sign-off. We also recommended a resilient rubber floor finish, with an enhanced specification for the free weights area, to control structureborne noise from gym activity, along with anti-vibration mounts for the sound system.
For the roof terrace, we advised on a teaching wall and canopy of solid, imperforate construction to screen existing plant noise. We also looked beyond noise control to the quality of the outdoor environment itself, recommending planting to encourage birdsong and the gentle movement of leaves to help foster a calmer, more pleasant soundscape for teaching and learning. Feasibility of acoustic screening from the rooftop glazed panel balustrade and between the outdoor seating booths was also explored.
To manage reverberation in the wellbeing hub, we specified a woodwool acoustic ceiling finish, sized to help the space achieve BB93’s target reverberation time, with an enhanced target expected to be achievable in most areas.
Throughout, we set out clear design guidance for the M&E engineer on duct velocities, terminal selection, and attenuation, to support compliance with the agreed noise criteria.
Result
The proposed design is expected to achieve suitable acoustic conditions to comply with the Independent School Standards, with one alternative performance standard identified for the ambient noise level in the wellbeing hub and clearly justified for the school’s approval.
The wellbeing hub’s floor build-up and absorption strategy will control both structureborne noise and reverberation, supporting a comfortable and usable space for staff and students. On the terrace, the teaching wall and canopy will provide meaningful screening from existing plant noise, and our soundscape recommendations give the design team a practical route to a calmer, more engaging outdoor teaching environment.
The defined acoustic strategy agreed at Stage 4 enabled the project to move into the construction stage with confidence.
Project Progress
Planning permission was granted earlier this year. A ground-breaking ceremony was held on 11th June and works are now nearing completion. For further reading head on over to Walter and Cohen website where the school’s Head of Student Support and Academic Access said:
“The new roof terrace will bring benefits to the whole South Hampstead community. Through the use of texture, fragrance, and colour, we aim to create a sensory-rich environment that supports calm and focus, particularly for pupils with anxiety, ADHD, and ASD. A central idea in planning the roof terrace space was to provide quiet, sheltered spots where students and staff can pause for a moment of reflection when needed, helping to reduce their stress levels and promote wellbeing. The lovely views, framed by trees, will offer a connection to the outdoors, encouraging curiosity and a sense of wellbeing.”
