The Project

Nottingham Girls’ High School is an independent school that educates girls from infants to sixth-form. Located in the heart of Nottingham, the school forms part of the Girls Day School Trust, the UK’s leading network of independent girls’ schools. With the aim to expand the school’s facilities, a newly built performing arts centre, which consists of a 275 seated auditorium, was constructed. This £9 million centre marks an important milestone in Nottingham Girls’ High School development and provides a state-of-the art facility for the performing arts department.

To coincide with school holidays, work began at the school towards the end 2015, with the first phase of the project installed by mid-December 2015. The whole project was completed by 30th July 2016.


The Challenge

As a performance arts block within the school grounds, acoustic performance was an essential requirement of the flat roof system, so this dominated the specification process. Tasked with completing the project’s flat roofing system, Nottingham–based roofing contractor, NRA Roofing and Flooring Services Ltd had to overcome two acoustic problems that are common in performing arts buildings: prevent the breakout of sound from the auditorium to surrounding areas of the school, and provide an efficient acoustic environment within the centre to reduce or remove any impact from external noises, including rain. The contractor had to demonstrate that the roof had been designed and installed to provide suitable control of rain noise reverberation and achieve a noise performance standard of LAeq 30dB.

NRA Roofing and Flooring Services Ltd had to take into consideration the requirements set out in Building Bulletin 93 (BB93), a document that explains minimum performance standards for the acoustics of school buildings. With all school buildings subject to detailed design checks and onsite inspections by building control bodies, NRA Roofing and Flooring Services Ltd also had to ensure all sound regulations were met.

As well focussing on the building’s acoustic performance, the roofing system was also required to meet thermal standards. As a new build auditorium, the building had to achieve thermal performances of 0.16, 0.18 and 0.20 W/m²K.


The ROCKWOOL Solution

A combination of ROCKWOOL flat roofing solutions was specified to accommodate the building’s thermal and acoustic performance requirements. The team at NRA Roofing and Flooring Services Ltd installed two layers of 5mm acoustic matting, followed by a polythene vapour control layer. The team then installed 319m2 of the 150mm HARDROCK® Multi-Fix (DD) underlay, 638m2 of the HARDROCK® Multi-Fix (DD) Tapered, over 325m2 of HARDROCK® Multi-Fix (DD) in 60mm, 85mm and 185mm thicknesses and 1010m2 of 10Kg/m2 ROCKWOOL® Acoustic Membrane onto the roof. The roof was completed with a bonded, single-ply waterproofing membrane.

Offering maximum density and exceptional dimensional stability, HARDROCK® Multi-Fix (DD) boards were installed with staggered and tightly butted joints on the roof. The HARDROCK® Multi-Fix board helped to deliver a comprehensive thermal, sound and fire safe solution that is suitable for this type of application. Designed to reduce the risk of ponding and standing water, HARDROCK® Multi-Fix (DD) Tapered boards were used to help maintain the acoustic ambience below the roof.

HARDROCK® Multi-Fix products are excellent sound level controlling products and fully compatible for use with other flat roofing systems to offer a thorough noise reduction scheme.

In addition to HARDROCK® Multi-Fix products, a ROCKWOOL® Acoustic Membrane was laid directly onto the structural deck of the roof with the HARDROCK® Multi-Fix (DD) Underlay placed across the roof. 



The inherent acoustic properties of ROCKWOOL products have provided the performing arts centre at Nottingham Girls’ High School with a highly efficient sound prevention system. In addition, ROCKWOOL insulation has also provided the school with optimum thermal conditions.

Project Location

Nottingham Girls School

9 Arboretum St

We required an insulation solution that would restrict the sound coming from the performing arts centre as well as provide an efficient acoustic environment within the centre. The ROCKWOOL roofing board’s open wool structure was ideal for absorbing and regulating noise in the building. Additionally, the acoustic membrane acted as a sounded deadening layer to prevent noise interruption during performances.

Kevin Dixon

NRA Roofing and Flooring Services Ltd
Project Manager
Nottingham School for Girls
Nottingham School for Girls
Nottingham School for Girls
Nottingham School for Girls
Nottingham School for Girls

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