St Edburg’s Primary School, Bicester

Project Overview

Background

In 2014, Wilmott Dixon led the creation of a new school in Bicester: St Edburg’s Primary School. It had a capacity of 420 pupils but subsequent housing developments in the area meant that by 2020, additional places needed to be found. Consequently, with no more room available on the existing site, the client – the Oxford Diocesan Board of Education – commissioned the construction of a satellite building, close by on the same Kingsmere development. On completion, it would accommodate the nursery, reception and key stage 1 classes. The original site could then be dedicated to teaching the older key stage 2 pupils.

Works began in September 2023, supported by input from a variety of stakeholder partners and specialist suppliers.

Brief

Valued at £12 million, the new-build project had several key objectives:

  • To provide places for 360 pupils, as required by local population growth
  • To free up capacity for key stage 2 pupils in the original (2014) building
  • To provide working environments with excellent thermal and acoustic insulation
  • To meet the requirements of the DfE Spec 21 specification, which requires ‘Net Zero in Operation’
  • To achieve a ‘very good’ rating to BREEAM standards

In order to achieve these standards, the new-build specification included energy-saving and resource-efficient features including air source heat pumps, solar photovoltaic panels on the roof, low-energy lighting systems and electric vehicle charging points.

Taking a ‘fabric-first’ approach, the design also made extensive use of insulation, including external wall insulation over cement particle sheathing boards, insulated floor and roofs, and energy-efficient doors and glazing.

In line with the DfE Schools Output Specification, the chosen external wall insulation system would have a design life of at least 40 years and should achieve an A2-s1,d0 reaction to fire classification (BS EN 13501-1:2018).

Design and Specification:

The chosen EWI system comprised:

When combined with Permarock SiliconeUltra K finish, Permarock Mineral Fibre EWI systems achieve an A2-s1,d0 reaction to fire classification and can be used on buildings of any height. The Schools Output Specification Technical Annex 2C: External Fabric dictates that “cladding on a school building with a storey 18m above ground level shall achieve Class A2-s1, d0 fire resistance or better.”  Similarly, it states that the same rating is required “where school buildings are prone to vandalism… for all special schools,” and for all residential areas of boarding schools.

The Permarock Mineral Fibre Insulation was supplied in boards measuring 1200 mm x 600 mm. They were installed in thicknesses of 250 mm. Other thicknesses were used as necessary to complete the detailed design of the system. All insulation boards were affixed using a polymer, cement-based adhesive and Permarock mechanical fixings appropriate to the substrate.

Permarock SiliconeUltra K Finish is a flexible, vapour-permeable render with a textured finish. It prevents water ingress and helps to maintain airtight facades that, in turn, help to minimise draughts and the movement of heat through walls. Permarock SiliconeUltra K uses nano-quartz technology to produce a finish that resists the accumulation of dirt, which it sheds through the normal actions of weathering, leaving facades cleaner for longer than when using traditional renders.

It also features a preservative that resists the growth of algae, mould and other organisms, so it tends to stay cleaner and brighter than conventional renders, thereby minimising routine cleaning and maintenance costs.

Performance and Sustainability

Permarock Mineral Fibre insulation is manufactured to EN 13162 and is CFC and HCFC free. It has zero Ozone Depletion Potential and zero Global Warming Potential.

Permarock Mineral Fibre External Wall Insulation systems have low embodied energy and are BIM Level 2 compliant. They exhibit thermal conductivity of 0.036 W/mK, and have an Ecopoints score of 0.10 (m2). This is classified as an ‘excellent’ rating.

They enable low U-values to be achieved in order to help meet or exceed standards including BREEAM, Passivhaus, EnerPHit and the Code for Sustainable Homes etc

Planning and Project Delivery

Permarock technical staff were actively engaged in the design stages, providing material and colour samples, thermal calculations, system detailing, BIM Object files and project visualisations. In preparation for works on site, they supported the delivery team by conducting preliminary pull-out tests for the mechanical fixings used to secure the EWI system to the substrate, followed by quality checks, ongoing troubleshooting and on-site technical assistance.

The EWI system was installed by Rendserve, a long-standing Permarock Registered Installer, which has received thorough training and has extensive experience of using Permarock systems. As a result, its teams completed the work effectively, to the required standards, and in a timely manner.

Result:

All works were completed on schedule in September 2024. Staff and pupils then made a smooth transition that did not interrupt learning within the school.

The fabric-first design has resulted in a building that is modern, attractive and very energy efficient. The mineral fibre insulation has played an important part in maximising its thermal performance, keeping rooms warm in winter and comfortable in the hotter summer months. It has also provided good acoustic insulation, minimising the risk of extraneous noises causing distractions to staff and pupils.

Client and Community Feedback

Councillor Liz Brighouse, Oxfordshire County Council’s Cabinet Member for Children, Education and Youth Services, said: “This extra capacity will have huge educational benefits for pupils at St Edburg’s CE Primary School. It is yet another exciting project from the county council, working with communities and partners on our commitment to provide first class education for Oxfordshire’s children and young people.”

The school’s head teacher Andy Terrey said: “With demand growing for places at the school, we knew we needed to expand our facilities. By constructing a purpose-built satellite school, we have the opportunity to create a brand-new building that is ideal for the needs of younger children … We’re also able to meet the needs of local families head on – with a further 1,000 homes expected to be built locally.”

Michelle Cotterill, director at Willmott Dixon, said: “The school is the oldest in Bicester, but it continues to move with the times – modernising and expanding its facilities to offer the very best for pupils, so we were really pleased to be involved in the school’s expansion.”

Tony Wilson, Director of Education at the Oxford Diocesan Board of Education said: “We are honoured to have been a partner in the realisation of this state-of-the-art construction … With our commitment to confronting the climate emergency, ODBE is delighted that this expansion is designed and built with sustainability as a key consideration. ODBE believes that the pupils of St Edburg’s CE Primary School will thrive and flourish in their new learning environment.”

Project
New Build / Education
Client
Oxford Diocesan Board of Education / Willmott Dixon
Specifier
Acanthus Clews Architects
Substrate
Cement Particle Sheathing Board on Steel Frame
System
Permarock Mineral Fibre External Wall Insulation Systems
Finish
Permarock SiliconeUltra K Finish