St Mary’s Catholic Primary School

Baxall secured the design and build contract via the Department for Education’s (DfE) Contractors Framework for the new 1FE St. Mary’s Catholic Primary School (located within the current school’s grounds), followed by demolition of the original school. With zero reliance on fossil fuels, St. Mary’s is one of the first Net Zero Carbon in Operation (NZCiO) schools in the South of England to be delivered on behalf of the DfE.

Baxall’s team commenced on site in summer 2023 working within a highly constrained and landlocked environment, with the existing (live/operational) St. Mary’s primary school metres away and segregated by solid hoarding.

The main structure of the new school building is a Modern Methods of Construction (MMC) closed-panel timber frame, manufactured off-site by Streif and selected for its low embodied carbon footprint. Baxall’s design team adopted a passive strategy to maximise natural daylight via external glazing, in line with the DfE Output Specification’s daylighting requirements. Energy-efficient LED lighting and controls, including absence detection and automatic daylight dimming, help to further reduce energy waste.

St. Mary’s is designed with a ‘fabric first’ approach, incorporating high levels of insulation and optimising air tightness. This state-of-the-art school exceeds the requirements of standard Building Regulations, minimising heating demand and energy consumption. Efficiency is further enhanced through the use of a highly effective heating plant, LED lighting, heat recovery systems, sustainable drainage solutions, and 136 photovoltaic (PV) units positioned above a biosolar green roof. The planting and substrate layers on the biosolar roof not only serve as ballast and additional insulation, but also promote biodiversity by enabling the entire roof area to be vegetated.

Baxall installed low carbon, highly efficient air source heat pumps (ASHPs) – which exceed Building Regulations’ standards – in addition to ceiling-mounted radiant panels. These work efficiently with the ASHPs with low distribution temperatures compared to conventional radiators.

Air handling units in classrooms incorporate heat exchangers to recover heat, while triple glazing on external windows and doors minimise heat loss (low U-values), maximise daylight (high LT Values) and minimise heat absorption (low G-Values). Internal heat gains are minimised via energy efficient LED lighting and insulating heating/hot water pipes. All façade-facing rooms have natural ventilation with hybrid ventilation systems and crossflow in all teaching spaces and main hall, thus avoiding mechanical ventilation.

Hot/cold-water consumption is regulated with water-efficient fittings and flow-limiting devices, with decentralised hot water to minimise distribution losses. Automatic monitoring of all energy sub-metering triggers alarms to alert facilities staff should the building’s energy consumption exceed typical levels.

Phase 2 comprised demolition and site clearance of the old school premises – including the creation of a new Multi-Use Games Area (MUGA), landscaping and pond area – once pupils and staff had moved into the newly built school. Permeable tarmac on the MUGA forms part of the Sustainable Urban Drainage Systems.

Following handover in September 2024 (in time for the start of the new school term), the building underwent seasonal commissioning to ensure all systems operated according to the original design intention and to the DfE’s Key Performance Indicators (KPIs) – including Urban Greening Factor targets.

Throughout the project’s life cycle Baxall upheld the ‘golden thread’ principle by ensuring accurate and accessible information for safety, compliance and transparency. The site team utilised Oculo for the first time, a construction technology platform featuring a 360-degree camera to accurately record site progress, enabling real-time visual documentation, remote inspections and enhanced collaboration amongst all project stakeholders. Oculo proved a powerful tool for both the client and wider project team, offering real-time reporting showcased at monthly client meetings. Due to its resounding success on St. Mary’s, Baxall has since rolled out the use of Oculo across all projects including site visits and inspections.

The team consistently achieved full marks on St. Mary’s against the DfE’s set KPIs, accompanied by positive feedback from the client, such as: “Baxall work well to share information and engage well with the project’s stakeholders” and “Baxall report in a timely manner and engage well.”

In line with the DfE’s requirements and Baxall’s own commitment to training the future generation of construction professionals, Baxall employed a T-Level student throughout the project from nearby East Kent College in Folkestone. Baxall also donated surplus bricks from St. Mary’s to the College’s bricklaying apprenticeship programme.

As part of its now-complete Knowledge Transfer Partnership (KTP) – which feeds into Baxall’s ‘whole life’ and building optimisation strategy – the team installed smart sensors in the new school to remotely monitor indoor air quality including carbon dioxide, humidity and radon levels. Baxall will share the data with St. Mary’s and the DfE to inform future environmental optimisation of the building and maximise occupancy comfort and wellbeing.

“Baxall work well to share information and engage with the project’s stakeholders”

Department for Education (DfE)