Madrid airport's new international terminal dwarfs Heathrow's T5, yet will cost half the price and be built in half the time. Building visited the site to see why things are going so well and found political will and national pride an unbeatable mix.
Saturday afternoon, and we're standing on a low hill outside Madrid overlooking the biggest construction site in Europe. It stretches as far as the eye can see and it is deserted.

"Nothing happens on the weekends here," says Mike Davies. "Everyone packs up at one o'clock on Friday." Two thousand workers have gone home; dozens of red-and-white tower cranes stand motionless and the legion of trucks, diggers and giant earth-movers is parked in orderly silence.

Davies is a director at Richard Rogers Partnership, the architect of the £700m international terminal at Madrid's Barajas Airport. Along with about 120 fellow workers from the London practice, he has come out to Madrid for the weekend. It's an office jolly with a bit of sightseeing thrown in – a tour around the mammoth airport project. Lord Rogers is here with his wife, snapping away with his digital camera and grinning with pleasure.

As we walk down a dirt road towards the main terminal building, most of the young staff are still discussing the previous night's revelries in central Madrid. For many of them, the wavy form of the terminal's roof will be familiar – RRP is also the architect of T5, the £2bn terminal-to-be at London's Heathrow Airport. But although there is a strong similarity in the design concept of the two buildings, the differences are more striking.

For a start, Barajas dwarfs its west London counterpart. "T5 looks tiny compared to this," says Davies, who is project director of the 445,000 m2 T5 extension, which will be the biggest project in the UK when it finally goes on site later this year. However, the Barajas site covers an awesome 6 km2 and involves constructing over a million square metres of buildings: a 470,000 m2 main terminal, a 315,000 m2 satellite and a 335,000 m2 car park for 9000 cars.

Then there is the size of the team: client BAA has a squad of about 500 working on the Heathrow project. In Madrid, the total is less than one-fifth of that. This may partly explain why Barajas is so much cheaper to build. "The cost per square metre is less than half T5," says Lennart Grut, one of the RRP directors working on Barajas. "Here, the whole team is small. Everything conspires to keep cost down."

Grut is keen to point out that, despite the long lunchtimes and mass Friday afternoon bunks, the Spanish easily match the Brits in terms of their work ethic. "We're gobsmacked by the quality at Barajas. When I first went to Spain I thought they'd be very southern European – have a bit of a mañana culture. But no way. Once they've made their mind up to do something, they get on with it."

The greatest contrast between the two projects is in their chronologies. RRP was appointed to T5 in 1989, but the first phase won't be ready until 2008. Over a decade was lost in a record-breaking planning inquiry that was resolved earlier this year.

Over in Madrid, RRP won the Barajas competition in autumn 1997, took possession of the site in May 2000 and is looking to hand over the job in late 2005 – more than twice as fast as T5. "That's five years from the start on site – which is an extraordinarily short time to build an airport," says Grut.

"Everything in the process in Spain is set to build things fast," Grut adds. "In Spain, theoretically there is a planning process, but if there's a political will, it happens. They work a lot more behind the scenes getting the interested parties to agree."

While T5 has been dogged by opposition, the Barajas expansion is a matter of immense regional pride, and prime minister Jose Aznar is personally championing the project. The terminal will give Madrid the fifth biggest airport in Europe, handling 70 million passengers a year – double the present number – and processing 120 take-offs and landings an hour. Madrid wants to poach a chunk of lucrative transatlantic air traffic from rival hubs such as Frankfurt, Paris and – above all – Heathrow.

Local residents appear supportive. The small town of Paracuellos del Jarama is only 500 m away from the site and its main road has been severed by the works. But when the town's mayor was interviewed by Spanish newspaper El Pais earlier this year, he sounded delighted: "Almost 70% of our working population has some kind of link with the airport. Because of the terminal, we anticipate to grow from 4000 to 25,000 inhabitants in four years."

RRP's involvement in the project began in early 1997, when Madrid practice Estudio Lamela asked the London firm to enter the competition with them as part of a team also comprising Spanish engineers and planners TPS and Initec. After winning, the team – with Rogers at the helm – worked up the final design. "We delivered scheme design and tender in 8-9 months," Grut recalls. "Normally, two years would be fast."

The design tries to resolve the great airport conundrum: how to build a structure that efficiently processes thousands of people going in different directions at the same time, while maintaining architectural elegance and environmental performance – in other words, how to avoid building a bloody great shed.

Rogers' concept starts by organising the main terminal building into four parallel linear blocks, each dedicated to a different stage of the airport's functionality. Each block has three levels – the upper two floors for arrivals, the lower for departures – and nestles under an identical elevated roof structure with the profile of a comedy moustache. The lightweight, perforated roof allows natural light to flood into the building – a technique borrowed from Foster and Partners' influential 1991 Stansted Airport.

The first block contains the drop-off zone where travellers disgorge from cars, taxis and buses. The second contains the check-in areas and the third, the retail and processing zones. The fourth block – which measures an awesome 1.2 km from tip to tip and is clad in floor-to-ceiling glass – contains the gates. This sequence is reversed through the lower, departure levels: gates in the first block, baggage hall in the second, processing in the third and pick-up in the fourth.

The terminal's design novelty is the "canyons" – three parallel, 24 m deep gorges that run between the four blocks. These allow light to penetrate the lower levels and create visual punctuations on the vast floor slabs, helping passengers to orientate themselves. The canyons are traversed by dramatic steel bridges.

Many of the design ideas are borrowed from T5. "Having worked for 10 years on T5, we'd come up with every conceivable airport solution," says Ivan Harbour, another RRP director. Site and budget constraints at Heathrow meant luxuries such as canyons had to be squeezed out, but at Madrid, the team is building exactly what they first designed. "In conceptual terms, this is better [than T5]," says Harbour. "This project went so quickly that we've never had the opportunity to do value engineering. We've ended up building the [original] diagram, which is wonderful."

The few changes the client has requested have been easy to accommodate. Aena, Spain's state-owned airport operator and Rogers' client, has cottoned on late to BAA's lucrative trick of shoehorning shopping malls into terminals and has now demanded swaths of retail. But the vast halls at Barajas can swallow this comfortably and unlike Heathrow, the architects get to design the shops, too. "We'll have more control than we'll ever be able to have at Heathrow," says Harbour.

Today, two and a half years after work started on site, the concrete work is nearly complete at the main terminal building and the canyons – protected by flimsy barriers – are a giddying sight. The modular roof of the longest block is nearing completion and contractors are trying out the rainbow colour palette on the steel columns. Far above, craftsmen have been experimenting with the stripped Chinese bamboo that will line the bays of the undulating soffit. On the floor, the first of 165,000 m2 of Spanish limestone floor tiles have been laid in a test area. They are so highly polished, they reflect the filigree steelwork above.

Along both sides of the building's stupefying length, the first panes of the 9 m high glass curtain wall are being installed. The glass is mounted on steel transoms suspended from slender tie-rods, which are 9 m apart and hung from the edges of the roof. These rods double as tensioning devices to keep the lightweight roof in place: each exerts a 45 tonne pull on the wavy roof trusses above. Even so, the roof modules – supported at the centre on slender V-trusses balanced on concrete piers – will sway in the wind, and the glass is designed to deflect up to 90 mm.

As we walk back up the hill to the buses, Mike Davies tells me about his last visit to the site. It was the week before, and he was accompanied by a high-powered delegation from BAA, his bosses at T5. "I thought it would be very useful to bring them out," he says. "They loved it."

We look back, where the skeleton roof of the terminal is silhouetted in the fading light. The ranks of swooping roof trusses resemble pterodactyls in flight and the construction team has already nicknamed them "the dinosaurs". I wonder what they would have thought of the men from BAA?

Getting the project off the ground

Whereas British airport operator BAA bombards its supply chain with novel procurement routes and ruthless benchmarking, Madrid airport client Aena likes to keep things simple. For a start, team sizes are pared to the bone. There are 40 people in the design team: five architects from Richard Rogers Partnership, 15 from Estudio Lamela and 15 engineers. There are also small consultant teams advising the client on quality control, cost and programme. The client team is just 15 people. There are no intervening layers of management; instead, the consultants report directly to the client. Their point of contact is a single person – the director del obra, or works director, who heads the client team and is in charge of the entire project. “All the decisions and responsibilities lie in his hands,” says RRP’s Grut. “It’s a totally different approach.” The director del obra is very much in control and can do pretty much as he pleases. “In one sense we’re at the beck and call of the client – he doesn’t have to listen to us,” says Grut. “You have to build up respect.” But he adds: “In Spain, there’s an acceptance of the role of the architect. Colours for example – that’s the architects’ decision.” The client also signs up and instructs the contractors, again without go-between management. At Barajas, all four main contractors and most of the subcontractors are Spanish. Dragados is building the parking and rail elements as well as the satellite terminal. The main terminal is being built by a joint venture between ACS, FCC, Ferrovial Agroman, Necso and Sacyr. Consultants advising the design team include Anthony Hunt Associates (structural engineering), Hanscomb and Gabinete (cost), Sandy Brown Associates (acoustics), Warrington Fire Research (fire) and Arup (facade).