Brand new sports kit

"In the early days of the lottery it was important to be seen to be spending the money," says Clapp, "so we knowingly funded a lot of pretty rubbishy projects." Instead, he hit on an idea that would guarantee lottery bidders a high-quality product at a low cost: an off-the-shelf design for a sports hall that could be repeated anywhere in the country.

Clients, he reasoned, would be able to buy a package containing a complete set of detailed designs, schedules and bills of quantities for between £300 and £400. They would then take the project to tender locally, saving £80,000 in design fees and up to a year in time. The entire sports hall could then be built in about six months.

And so, 13 months ago, Clapp assembled a design team to come up with the Optimum Sports Hall. "We deliberately chose non-specialists," he says. "There are architects on the RIBA register who hold themselves out as specialists but who have been turning out awful buildings." Instead, he selected architect Studio E, which had designed just one sports building: the swimming pool at Haileybury School in Hertfordshire. Despite the firm's lack of leisure experience, it was one of the best small leisure facilities Clapp had seen.

The rest of the team consisted of structural engineer Techniker, services engineer Max Fordham & Partners and cost consultant David Langdon & Everest. Clapp also appointed Willmott Dixon buildability consultant to ensure that each part of the design could be produced easily and cheaply.

Their brief was to design a centre containing a standard 33 × 18 m sports hall, a dance studio and an exercise studio, plus a reception area capable of housing a cafe or community facilities. In addition, the centre had to contain high-specification changing rooms, plus space for staff and plant and equipment storage. The need to keep building costs down E E drove the whole project, and a cost model was drawn up based on the best-value sports halls in the country. "We monitored everything against that model," says DL&E's Tony Brennan. "It was both exhaustive and exhausting." Once the basic design had been worked on, each component was ruthlessly value-engineered. Rooflights over the courts were thrown out: "They invariably leak and it's expensive to produce glare-free light," says Clapp, adding that water damage to wooden court floors is a major avoidable expense in centres.

Glazed end-walls – de rigueur in many leisure centres – were axed after whole-life costing found that the saving in electricity bills would not justify the initial expense: each centre is calculated to cost £1400 per year to light, while a glazed wall would cost about £15,000.

Likewise, a concrete floor slab beneath the hall was rejected in favour of tarmac. "It can go down in any weather, it's easier to get the tolerance and it's half the cost," says Clapp.

Design fripperies were swept away with equal ruthlessness: Studio E wanted to put a step in the roof where the main hall met the ancillary area, but this was dropped after DL&E calculated that the feature would add £22,000 to the build cost.

Following consultation with private leisure operators, the initial layout changed to accommodate larger exercise and dance studios to make the centres more commercially viable. The final layout allows the hall to be divided off from the studios so that schoolchildren and adults can use the facilities without mixing.

"We were not only interested in funding the hall, but it had to work economically," says Clapp. "We have to fund the fitness and exercise studios in order for the centres to survive." Sports halls are often little more than industrial sheds in both structure and appearance. The design team was encouraged to refine their structural solutions as far as possible. Instead of the standard industrial portal frame with heavy columns and ugly haunches and braces, Techniker designed a slender, braced steel frame that can be built at the same cost. "We worked very hard to get the weight down," says project engineer Kevin Lyons. "Our objective was to make this thing highly buildable but we wanted to prove we could get away from the portal frame shed." Apparently, the curved aluminium standing seam roof has an unexpected benefit: high shuttlecock visibility. "It's better for badminton players," says the brochure.

Despite the team's best efforts, the hall, with its profiled steel cladding and curved roof, still looks somewhat like a crinkly tin shed. However, it promises users a surprising degree of comfort. The changing rooms feature underfloor heating and natural light, while automatic doors and intelligent lighting – operated by presence detectors – are used throughout. Even the colours of the walls were researched in depth to identify a range of shades that gave the optimum lighting conditions on the courts.

Many of the components, such as lights and heating systems, were developed specially in collaboration with product manufacturers. Clapp hopes that as more Optimum centres are built, suppliers will begin mass-producing components and improving on the initial design. "The concept is for a product that, following the Egan philosophy, will be improved and improved. It's more akin to producing a car that will be improved over time. As we build more and more, the price will drop." But the first sports halls will go out to tender locally and largely be built in the traditional way. After initially considering prefabricated wall panels, the team opted for painted 140 mm blockwork since this worked out far cheaper and gave the added benefit of providing temperature control in the summer.

Clapp hopes Optimum will give schools and community groups that would otherwise be wary of embarking on a building project – particularly those in poorer urban areas – the confidence to bid for lottery funds. The complete drawing package should prevent many of the claims that arise when architects' drawings arrive late, making final costs predictable. In fact, clients will only have to employ a design team to deal with site-specific details such as ground conditions and access.

Since the Optimum project was started, the government has announced a new £600m pot of money to fund school sports facilities over the next three years. Sport England hopes that much of this cash will be spent on their new product; up to 400 Optimum halls could be built across England.

Negotiations are now being finalised for the first prototype at a school in Dagenham, Essex. "We're very anxious to get the first ones up because until people see it, they're not going to believe they can get so much for so little," says Clapp. "Once the first ones go up, there will be no turning back for sports halls."