Examining both primary and secondary schools, including a five to 18 all-through school, each team was given a site specific scenario – including confined inner-city and rural sites – and asked to come up with a RIBA Plan of Work Stage C or D.
The brief required that they be inspirational, cost-effective designs that would stimulate pupils and teachers alike; be flexible to allow short-term changes in teaching methods and adaptable to enable the size and number of classrooms to be altered at a later date. At the very least the environmental design had to meet the standards of Building Bulletins 87 and 93 and be suitable for some degree of off-site construction. In addition the design teams had to demonstrate that their schemes could be adapted to cope with a number of variations to the core brief, typically responding to different curriculum or organisational requirements, or variations in the size of the school.
The teams were made up of both small and large practices, these included architects, cost consultants, structural engineers and environmental engineers. To make the design process realistic each group was allocated a partner school to help identify their needs and question some of the traditional design approaches. They were also assigned a 'buddy' within the Schools Building and Design Unit to act as a client and be their first point of contact within the DfES to offer advice.
Key themes
A number of ideas and concepts emerged from the designs put forward and these developed in different ways to meet a broad range of issues. A lot of consideration was given to the spatial arrangement of buildings. Increasingly, schools are used out of hours by the community at large and this was often reflected by having clear separation of the main school buildings from those used by the community. Those on confined sites, which used multi-storey solutions, regularly allowed the ground floor to be accessible to the community with shared amenities, while the main school facilities were located on the upper levels where access is more tightly controlled. Another common concept was the idea of a 'school within a school'. This was prompted by the notion of schools in the future varying the length of the school day, as well as introducing vocational studies and organising themselves into smaller units. The concept allows the general teaching spaces of a single unit to be grouped in a distinct area, with only large performance spaces being shared.
Interestingly the report states that the need for shared information and communication technology (ict) resources may be declining. 'In discussions with heads and educational advisors, the secondary school exemplar brief is based on the option of large classrooms, to allow for an increasing amount of ict in the class (as well as further inclusion of pupils with special education needs or disabilities), and assumes IT rooms are only needed to teach IT as a subject.' This will certainly be the case if, as is likely, ict becomes smaller and more mobile in the future.
Many of the design teams developed schools which were effectively a 'kit of parts' that could be assembled at the early design stage to accommodate schools of different sizes and age ranges. Open plan arrangements were commonly adopted for parts of the school, allowing future adaptability. Learning areas that could provide a traditional arrangement, or be used as larger rooms with smaller seminar rooms adjacent were common. Linear cloister arrangements were developed by many of the teams in response to the issue of adaptability. Schemes incorporating lines of classrooms off an extendable circulation route were developed. This can lead to long travel distances in larger schools, however the variety of classroom sizes can be achieved by moving walls both between individual classrooms and classrooms and corridors, effectively using the corridor as a shared teaching space.
Learning clusters of between four and five classrooms, were also prevalent particularly in the secondary school schemes and all-through school. For instance, BDP's multi-storey 'beehive' school uses a hexagonal module as it basis (shaped like a piece of honeycomb), wrapping around a closed central area which offers a space for children away from the dirt, noise and fumes of the street. However, while these provide a sense of community for year groups or houses, the cluster approach can have a negative effect on adaptability. 'Even in clusters of six, a seventh classroom is inevitably left out in the cold with less links to the group' states the report.
The often overlooked area of acoustics was tackled in many of the designs with the introduction of acoustic ceilings and baffles to reduce reverberation times. The use of moveable walls rather than screens and furniture to divide up open plan spaces was commonly adopted to satisfy acoustic and flexibility requirements.
Environmental design
Comfort was one of the key considerations invested in the designs and was recognised as a vital attribute for any building used for teaching and learning. Careful consideration of orientation and the adoption of heavyweight construction have allowed many of the schemes to provide high thermal mass as a means of stabilising internal conditions throughout the year. All designs chose to supply 100% fresh air with no recirculation, most opting to provide a best practice 8 litres/s, despite the current minimum requirement of 3 litres/s. However natural ventilation, mixed mode and full mechanical ventilation have all been explored.
Over the next 10 to 15 years £2 billion a year will be spent on ‘Building Schools for the Future’ with the aim of rebuilding and renewing all secondary schools, along with substantial investment in primary school buildings.
Buro Happold was environmental consultant on Alsop's tight urban site school. This uses a mixed mode solution for the classrooms whereby fresh air is drawn in at low level and distributed around the building through the raised floor voids. Large opening windows provide natural ventilation when the external air temperatures match the internal requirements for ventilation and temperature. In the summer the system operates overnight to provide a secure way of cooling the exposed concrete slabs. Buro Happold also adapted a similar scheme for Feilden Clegg Bradley Architect's large urban site scheme. A labyrinth below the structure is used to provide pre-heating in winter and cooling in the summer to ventilation air.
Atelier 10 opted for a mechanical system on Penoyre & Prasad Architects large urban site scheme, predicting it will have lower energy running costs than a naturally ventilated approach. The prototype facade system used to clad and insulate the building incorporates local mechanical ventilation with sound attenuation to ensure sufficient fresh air is fed directly into the classrooms. Significantly the energy required to heat the incoming air is higher than the heat losses. 'Heat gains in a school are around three times as great as the conduction heat losses. A 60% efficient heat exchanger to the ventilation system will be sufficient to reduce the overall heating load to zero, apart from the 10 minute warm up period in the morning.' Night-time cooling of the mass however is still achieved through high level windows at night. Excluding abnormals, the cost estimate for the scheme is within the DfES net building cost guide, however the novel approach to the mechanical and some of the electrical services distribution will need to be carefully considered and costed in detail.
Natural ventilation schemes vary in their complexity. Max Fordham LLP was environmental consultant on Cottrell and Vermeulen's sloping site primary school. Here they went for natural ventilation utilising a temperature and pressure driven stack effect system. A series of buried vitrified clay pipes supply fresh air to each classroom with stale air extracted via a central ventilation chimney. Mechanical ventilation is only required in the toilets, main hall and kitchen.
Wilkinson Eyre's sloping site school comprises of two building types: learning clusters and central facilities (containing assembly, sport dining and admin spaces) linked by a covered street. In the learning clusters Arup adopted a natural ventilation approach that relies on rooftop ventilators to provide each of the 3·3 m tall classroom spaces with good ventilation without noise transfer.
Much use has been used of clerestory windows, north lights and roof lights in the schemes to maximise daylighting of the internal spaces. Atelier 10 also proposes that, with the predicted lower than average build costs, its scheme will be able to include venetian blinds within the triple glazing to cut out glare and heat, yet reflect sunlight and daylight onto the ceiling using technology such as Serraglaze or reflective venetian blinds. In this way large areas of glazing with blinds down and the lights on is avoided.
One of the most ambitious schemes put forward by de Rijke Marsh Morgan Architects, with environmental engineers Fulcrum Consulting, for a rural site secondary school, sits beneath a vast ethylene tetrafluoroethylene (etfe) dome. This mainly transparent structure creates a huge volume in which a variety of classroom types can be configured and also creates an unusual inside/outside space with its own macroclimate. This ties in with the daylighting scheme, whereby the triple layer variable transmission etfe skin enables control of direct solar gains and delivery of appropriate daylight levels deep within the building.
The reality
While the compendium of designs isn't intended as a set of templates, the individual schemes are meant to stimulate imaginative and sustainable designs for the future. They also highlight just how much future schools will rely on the input of building services consultants, not least in the m&e services but also in the treatment of acoustics and lighting (both artificial and natural).
Over the next 10 to 15 years around £2 billion a year will be spent on 'Building Schools for the Future' with the aim of rebuilding and renewing all secondary schools. And over the same period there will be substantial investment in primary school buildings. The legacy of the last major schools building programme is still with us. The many over-glazed, poorly insulated and often leaky buildings of the 60s and 70s have high running costs and often don't provide the learning and working environments needed today. For building services engineers this marks a great opportunity to make sure the same mistakes aren't made again.
Source
Building Sustainable Design
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