Design process

The design project started with visits by the headteacher and a small group of stakeholders to a number of local schools. From these visits the school composed a wish list including a central street, outdoor spaces for each of the classrooms, a separate entrance for foundation-stage classes and adequate storage.

The county council was keen that the building should contribute to the sustainability agenda for Worcestershire. The architect put considerable effort into testing the design throughout its development stages using the UK Climate Impacts Programme (UKCIP) adaptation wizard. This made it possible to assess the impacts of climate change on the proposals, the design and construction phases and through the design life of the building.

The building had to be located on the lowest part of the site even though this area is potentially prone to flooding. This risk has been addressed by creating a sustainable urban drainage scheme (SUDS), using swales, ponds and underground box storage. The SUDS is used as an educational tool to support environmental studies and other curriculum subjects. This was designed by the landscape consultant, who has particular expertise in this area. A rainwater harvesting scheme storing up to 20,000 litres of water beneath the playground is used for flushing toilets. An overflow from this discharges water into a channel adjacent to the playground so that pupils can see when the tank is full. A sedum roof is also used to reduce run-off. Large overhangs on the roof and canopies protect level thresholds (required for disabled access) from heavy rain.

The risk of mould growth during predicted milder and more humid winters has also been considered. There are no cold spots (‘thermal bridges’) in the building fabric, ensuring continuity of insulation. All vulnerable areas are well ventilated, particularly wet areas like toilets and showers. Proprietary extract vents are powered by small photovoltaic panels.

The building is heated using ground source heating feeding an underfloor system. A total of 33 boreholes were drilled to a depth of 100 metres and water is pumped through them to obtain a small temperature increase. Heat pumps, run on electricity purchased on a green tariff, then raise the temperature to the level where it can feed the underfloor heating system and provide domestic hot water. Cooling in the ICT suite is provided by running the ground source heat pumps in reverse. Overall, the school reduces carbon dioxide emissions by 20 tonnes each year compared with using fossil fuels.

The main framing material for the school is steel. This helps form the curved geometry of the building and provides some future flexibility, as internal walls are non-loadbearing. Internal and external walls are mainly timber framed, which was chosen as a renewable resource with low embodied energy content. This was used in conjunction with high levels of insulation, using materials of high recycled content. For robustness and for added thermal mass, both sides of every internal wall have a double layer of plasterboard. The zinc roof is fully ventilated beneath the timber boarded substrate which supports the zinc, allowing warm air to circulate naturally in summer, reducing heat transfer into the building.

The specification for the building was reviewed by the Waste and Resources Action Programme (WRAP) as a pilot scheme, and this enabled the architect to identify any materials that could either be recycled or have a recycled content.

An artist worked with the pupils during the design stage, creating work that reflected sustainability and environmental issues. This has been incorporated into stained glass panels that are set into the windows facing the internal courtyard. External art work is also prevalent in the form of sculptural pieces found in the growing garden and the internal courtyard. The school grounds have been developed and have a variety of external spaces for pupil play and educational activities. Along with the SUDS, swales and ponds area there is a terraced growing garden which is actively attended by the pupils.