A film about architect Frank Gehry and his iconic Guggenheim Museum opens tomorrow. Emma Cullinanreports.

The world has been reeling from the Bilbao effect for a full 10 years now, though it seems like only yesterday that Frank Gehry's steel and titanium angular building put the northern Spanish city at the centre of the world design map.

The person commissioned to film the glistening museum for its first decade commemoration is Dublin-born Ultan Guilfoyle. Around his neck hangs a security pass that - like expiring passport photos - shows a man 10 years younger. "I filmed the first shovel going into the clay," says Guilfoyle, who now lives in New York.

He is also the producer of a documentary about Bilbao's architect: Sketches of Frank Gehry, which was directed by Sydney Pollack. It opens at the IFI in Dublin tomorrow.

"Ten years ago Sydney Pollack, who had known Gehry for years, was in Barcelona and Frank invited him to the opening of the Bilbao Guggenheim. Pollack did wonder why anyone would go to an opening of a building but he said, 'I have a day off so let's have a drink anyway'. But when he walked around the corner and saw the building his heart stopped," says Guilfoyle.

A few nights later, at a dinner attended by the trio, Gehry said: "Why don't we make a film of all this?" Guilfoyle got the call from Pollack a year later.

The result is a documentary that follows Gehry as he visits buildings and designs, and talks. We get his views on design, his career and architecture although this isn't for those seeking an in-depth study of design: it instead gives an insight into the architect, not least through the views of his therapist.

It took five years to make. "We both knew Frank had a relatively short attention span. Sydney and I knew we would only get him good for a certain amount of time. Sydney, I found also, had a short attention span and he gets bored. So we bought two mini video cameras and said, 'Let's just shoot Frank in the most relaxed way with no film crew, no stuff'."

Guilfoyle says that if they had known it would take five years they may have thought twice about making the film - but it was worth it.

The aim - without the archi-speak - was to get inside the way Gehry designs although, if you took the film at face value, you might think it involves cutting up pieces of silver cardboard and sticking them to each other. There are telling insights, such as the way in which architects can spend their careers waiting for the one incredible building but, as Gehry says, he gradually learned, "There is no there." Although many would say that Bilbao was his "there". There is also an insight into how a mistake by builders at Gehry's building for Vitra led the architect to use computers.

"We made the film to get inside the process. Sydney was very clear about this. He wanted people to see the artistic process at work and how the aesthetic emerges. Here was a guy who didn't find real success until he was into his 60s and who had gone against the tide for all of his career. Not just to be cranky or individualistic but because he has a process and an incredible and intelligent understanding about buildings," says Guilfoyle.

His involvement in documentaries about architects began in the late 1980s, when he lived in London and ran a production company with Bob Geldof. They made arts programmes for the South Bank Show and pitched the idea of a documentary about Frank Lloyd Wright. "We made the documentary in the late 1980s when there were arguments about modern architecture, with Prince Charles joining the debate and the worst architecture was being inflicted on Britain. We did the film with Richard Rogers who suggested that we focus on one building - the Guggenheim. That's how I came to know the Guggenheim people."

Through meeting Rogers and other architects in London, Guilfoyle was also involved in the setting up of the Architecture Foundation. The Wright film led to Guilfoyle leaving London for New York, where he ran the film department at the Guggenheim. There he worked on an exhibition of motorcycles along with Frank Gehry and got an insight into how the architect worked. "He was very engaged and every day his team would send through drawings, so it was not a static process. And that's the way he works with clients: he is engaged and the client is engaged. It's not as if he goes away, designs something and comes back a year later."

Guilfoyle was, then, perfectly placed when the Bilbao Guggenheim was mooted. "The Guggenheim in New York is tiny and they were looking for a way to address the fact that late 20th century art was getting bigger. We were also moving out of white cube. If you visit an artist's studio you rarely see an expanse of white wall, yet there is a desire to exhibit art in white boxes.

"The link with Bilbao was a perfect coalition of forces. The politicians in Bilbao had an inkling that, if they created something wonderful, it would turn the city around. They were dealing with a real crisis. There was high unemployment. It is the classic story of a rust belt: where heavy industry had gone bad. They asked Norman Foster to design subway stations - these are now known as Foseritos. And Calatrava did one of his first bridges here and designed the airport. At the same time they were talking to the Guggenheim and said that they wanted something like the Sydney Opera House."

Guilfoyle was perfectly placed to watch the museum evolve and to get to know Gehry. "I had the best seat in the house. Imagine sitting in a room with one of great architects of our time and one of the greatest directors. I was there for a long time and got to eavesdrop on this conversation. It was an incredible privilege."

Sketches of Frank Gehry is at Dublin's Irish Film Institute from June 29th to July 8th.