Giles Deacon: cutting a splash

Phew, I'm hot!' announces Giles Deacon, bounding athletically into the ES photo shoot. 'I could really do with a shower - I've just been cycling.' Crop-haired, muscly and wearing his trademark ostentatiously enormous Aviator specs, a yellow polo shirt and jeans, Giles looks a bit nerdy. If you didn't know who he was, you'd probably think he was a website designer.

In fact, Giles, 39, is the proud owner of one of the most impressive CVs in the British fashion business. A couple of years out of college, he successfully relaunched Bottega Veneta, then worked for Tom Ford at Gucci. His own first collection, which he showed in 2004, was modelled by the sort of supers who wouldn't normally soil their platforms with the dust of a catwalk (Karen Elson and Eva Herzigova). In 2006, he was voted British Designer of the Year. Just last week he won the ANDAM award, a fashion Oscar given by the French Ministry of Culture. This means an extra £160,000 to play with and a Paris catwalk slot.

He's designed for Mulberry and Louis Vuitton and for several years has been creating a designer diffusion line called Gold by Giles for New Look. 'The supply base and the speed of the turnaround are incredible,' he says in his soft Cumbrian accent. 'I really enjoy it. The whole concept of designers and the high street is well-established now, but when we first started there weren't many doing it. The reason I wanted to work with New Look was that they wanted to stick with one designer and do lots of collections a year. So I can reach people who don't know who I am but they know the line, and that's what I wanted. I love the idea of democracy of design. Even if you have a lot of money, you may not want to spend a lot of it on clothes.'

His new swimwear collection for the high street label, which also includes beach bags, kaftans and studded flip-flops, has just been launched, which is why we have met here at the unfeasibly glamorous swimming pool of the Haymarket Hotel.

(Left) Giles with Agyness Deyn at the Giles after-party at London Fashion Week last September

In contrast to Giles's own resolute sartorial practicality, the Gold by Giles woman (who he thinks of as a cross between Agyness Deyn and Drew Barrymore) will be wearing heels and jewellery to the pool this year. The graphic monochrome patterns on the swimwear were inspired variously by book jackets (he cites a Tama Janowitz book with a scribbly cover, and an old copy of Evelyn Waugh's Vile Bodies 'which is quite a good one to have for poolside reading'). 'People are often a bit more adventurous with swimming costume prints; they like the idea of something a bit more jolly,' he goes on. 'I really like the black and white graphicness of my costumes. People have said they're 1980s-style but I think of 1980s swimsuits as really high cut, Victoria Principal-style. I don't think most girls are keen on that unless they've got legs like a giraffe.'

The other major inspiration for the line came from a stay at the Chateau Marmont. 'I go to LA three or four times a year. It's great for research. I'm terrible at going on holiday, but it's a great excuse to see friends and look at vintage stores. I can get a hell of a lot done there. It's the exact opposite to London - it's meetings by the pool and you see people wearing swimwear as daywear. The LA girls are very different from London girls. They're not edgy but that's part of their mass appeal. In my fantasy other lifestyle, I could definitely consider moving.'

Meanwhile, he bases himself in the less fashionable part of Islington, and reputedly leads an ordinary sort of life, swimming, gardening and meeting friends in the pub, even if those friends are likely to be Katie Grand, Agyness Deyn and Alexander McQueen. He strenuously avoids the excesses of his industry. 'The era of designers being away with the fairies is gone,' he declared recently.

So what does he think of Brüno? He rolls his eyes contemptuously. 'I'm not a huge fan of Sacha Baron Cohen at all,' he says. 'I'd be naïve not to say that fashion is about posturing and showing off - stress over sequins - but within it, it's a very important business that employs a lot of people. It's a grafting, full-on job. The timelines are super-strict and everyone works incredibly hard.' He goes to his studio near Brick Lane at 10am every day and works till 8.30 in the evening. No wonder he was appalled by the behaviour of Karl Lagerfeld, who kept him waiting for eight and a half hours to do an interview (Giles had briefly turned his hand to journalism but didn't repeat the experiment). 'I just thought that was a little rude.' That's not Giles's style (in fact, in what may well be a fashion first, he actually arrived early for our interview).

Giles has no fashion in his background. 'Well, I can't think of one designer who comes from a line of designers,' he retorts rather defensively. He was born in Darlington and spent most of his childhood in rural seclusion in the Lake District, roaming the hills for hours on his own, drawing animals and plants. His father, David, worked in agricultural sales; his mother, Judith, was a housewife who enjoyed flower arranging. His elder sister teaches riding, and Giles was a keen horseman as a teenager.

Art, rather than fashion, was his passion. He finds it weird when designers claim they spent their childhood drawing frocks for their grannies - he wasn't particularly interested in clothes. 'The world of creativity definitely interested me,' he says, 'but it could have been animation or music. I used to go to Newcastle a lot with my mate Glen and buy records at HMV because we liked the covers, and get magazines like The Face and i-D.'