Iain Borden is a professor of architecture and urban culture at the prestigious University College London. But his teaching is also about skateboarding: his passion.

When you first meet Iain Borden, you can't really imagine him skating through the city of London or hanging around at Southbank with the cool kids. His wire-rimmed glasses and his black shirt give him an academic appearance. His look definitely fits in better at his office at the University College London (UCL), packed with books about urban culture and architecture, than in a graffiti-covered skate park. "I wouldn't call myself a hardcore skater anymore, but I still love to go down to Brixton with my long board from time to time," says the 51-year-old with a wink.

Borden had his first skate experience in London, at the Undercroft at the Southbank, the epicentre of British skateboarding. He was one of the first skaters to use the dead space when he was around 16. "I used to come with my friends and at least at one occasion we even slept at Southbank over night and skated in the morning in the sunny open-air," he says. Recalling those days his blue eyes light up and a bright smile appears on his face. Only the crow's feet around his eyes reveal his real age in that moment.

In his 20s Borden broke his leg while trying a new trick at a half-pipe. It was a complicated fracture and he had to stop skateboarding, only to pick it up again years later during his time in America where he earned his doctoral degree at the University of California. But in retrospect, Borden's time at the Southbank gave him the initial impulse to think about skateboarding in an academic way that connects it to architecture.

A post-war critical urban youth movement

Skateboarding is for Professor Borden more than a sport, it's a way to take part in urban culture and provides a gathering place for young creatives. "Skateboarding normally attracts people who are not quite into team sports. They are more individualistic with having a bigger connection to art, photography, journalism, creative writing, but also entrepreneurship - the biggest shoe-companies nowadays are run by people with skater-backgrounds," he says.

Skateboarding is also an opportunity to co-create spaces and facilitates a new way of looking at architecture. "Skaters have a special perspective, one that allows them to see buildings and spaces beyond what they were intended to be," he says. "It promotes a critical attitude to the world outside." Skaters perceive public spaces as a collection of tactile surfaces to be jumped on, grinded, and conquered.

A bench in a public space is no longer simply a place to sit as the architect or designer intended. A skateboarder sees a bench and contemplates. How many different ways can I engage the form of this bench with my wooden board, metal trucks and wheels?

Utilizing a vast archive of skateboarding magazines as sources of historical evidence, Borden has observed what skaters thought was significant at certain places and times, and how they co-created spaces and areas. In his PhD thesis he details how skateboarding evolved from a modified scooter for children in the fifties, to being a leisure-time activity reserved for U.S., west coast surfers in the 70s, to being a youth subculture which exists today. In 2001 Borden even published a book on skateboarding called ' Skateboarding, Space and the City: Architecture and the Body.'

A unique and occupied space

According to Borden the Southbank Undercroft demonstrates his theory that skateboarders apply a critical perspective towards architecture. He shows pictures of the old Undercroft space in his over 400 page doctoral thesis. A whole chapter is devoted to the iconic skate park.

Borden sees the space at the Thames as a so-called SLOAP - a space left over after planning. The lecturer enunciates every single word of his invented word and underlines it by pointing his fingertip in the air.

"The Undercroft in the 1970s was meant to be a dead space, not to be a space for skateboarding. The architects creating this area had the idea that if you left space over people will find alternative use for it, so in a way the skateboarders were doing what they were expected to do and took over the space," says Borden in his posh British accent, which makes him sound like an absolute academic.

With expansive hand gestures the professor describes other aspects which interest him - like the architectural qualities of the Southbank. When drawing the heavy monumental structure, the low ceiling, the changing patterns of light and the extraordinary sound provided there, Borden can't stop rhapsodizing. "It's a bit like Wembley Stadium: it has a historical quality and it's a very unique feeling to skate there," he says.

But even more important for Borden is the floor. It plays another important function in the professor's theory about skateboarding. "The vibrations, the textures and the surfaces of the city come up through the skateboard into your body. You actually feel the surface of the city as you move around. It's an almost sexual experience," he says and laughs out loud at his unusual comparison.

His smile only freezes when confronted with the possible replacement of the Southbank Undercroft with café's and restaurants. The professor is member of an expert panel and involved in the ongoing discussion about the future of the skate park.

For the professor the issue is more than just a fight between skateboarders and businessman. "In a way it's a discussion about how we want our public spaces to be," he says. "Do we really want our public spaces turning into a soya-latte-macchiato-café culture?" Borden raises his eyebrows critically.