Don't be fooled by the foppish style: Britain's favourite interior designer is set to have a say in the way we build entire towns. Which may be of interest to Prince Charles … we find out more.
"You're not just going to talk about his hair and his cuffs are you?" Laurence Llewelyn-Bowen's assistant asks nervously after the interview. As if I would. Of course, he is well known for his impeccable dress and grooming – Beau Brummell out of Duran Duran – but there is much more to him than visibility. The 38-year-old front man of Changing Rooms, the dashing cavalier of mass-media interior design, the crown prince of medium-density fibreboard, has plans to change entire towns.

More specifically, LLB (as he is known to friends) has been hired by housebuilder David Wilson to design its showrooms. But if he has his way, he will soon be designing the layout and architectural detailing of entire estates. Cynics may see this role as a PR stunt – The Mirror called him the 80th least influential person in Britain earlier this year – but this would be to underestimate the seriousness with which he is taking his task, and the importance of the year 2003 in the history of post-war British housing.

Surprisingly, there was a time when LLB wasn't on our televisions. He actually began his career working for the Harefield Group, a flooring and door maker, before setting up his own design firm.

His commissions there included interiors for Christie's auction house and the Richmond and Criterion theatres in London. This man is capable of higher-level activity than embellishing perfectly good living rooms with gold stencilling and purple felt. He is part of the great tradition of British design … "gently updating tradition, merging contemporary and historic, making it genuinely very exciting".

Traditional housebuilders can be very mealy-mouthed and brief designers to create schemes that are not going to excite anybody

This job description locates LLB pretty much up to the second with respect to the après-postmodern British zeitgeist. As Building has reported in recent weeks, we are on the verge of a 200,000-unit housebuilding programme, and it is looking more and more likely that a leading model for that programme will be Poundbury, Prince Charles' faux-trad vernacular community in Dorset. LLB loves Poundbury. Not only does it gently update tradition and merge the contemporary and the historic, it is popular as well.

"Ten years ago, everybody was so scathing about Poundbury," E E says LLB. "It's reinventing the past but it looks ravishing. People are enjoying living there. It's being taken a lot more seriously now. The past is getting sexy."

LLB then launches straight into his deep interest in the nation's housing stock. He seems to think we may not be faring that well compared with, say, the Victorians or Georgians. "Doing a programme like Changing Rooms, you see every imaginable habitable dwelling. I have been wondering over the past few years how we are going to be perceived by future generations, where we will fit into architectural history," he says. "I don't think it's something we have the right mindset or imagination for." But he is excited by the way design has become a British preoccupation. "The market is so more design-literate than it was 20 years ago. Every level of the industry, from housebuilders to developers and manufacturers – all of them have to keep abreast of what's happening."

As LLB sees it, the market has developed and housebuilders have not. Their products have to be updated if they are to appeal to the newly design-savvy buyer. "One of problems with architects and housebuilders is that they don't have the user in mind," he says. "Charles Rennie Mackintosh talked so little about architecture but one of the most fantastic things he said was that spending time on the detail of buildings shows love. I feel very strongly about that."

And he is scathing about the way showrooms are presented: "Traditional housebuilders can be very mealy-mouthed and brief designers to create schemes that are innocuous and are not going to excite anybody."

In contrast, David Wilson's output ticked all Llewelyn-Bowen's design boxes, ranging from the company's architectural mix to its "sexy" use of different materials. "I was very interested when I saw what David Wilson was doing. It was something that struck a chord, the idea of updating the past rather than creating enormously aspirational statements of the time. The developments were also very carefully thought-out in terms of the end user.