When Established & Sons, the new British furniture company with a facetious name, launched two years ago at the Milan Furniture Fair, it literally took the roof off. As its 4m Aqua table (designed by the Iraqi-born architect, Zaha Hadid) proved too big for the door, the company hired a crane and sawed through the metal roof struts (to be re-welded later) to winch it into the pavilion.

Since then, Established & Sons has deftly and repeatedly made international waves. Sometimes this is because of its sheer coolness: the guest list to its first birthday party included Gwyneth Paltrow, Scarlett Johansson and the cult stylist Rachel Zoe, alongside the company’s CEO Alasdhair Willis, his wife Stella McCartney, and father-in-law Sir Paul. Sometimes this is because of its flashy success, as when a prototype of the Aqua piece sold for $296,000 at auction in New York. And sometimes this is because its critics suspect its dramatic ascendancy owes more to hype than intrinsic quality. Recently, a controversy surrounding an Established & Sons side-table started by internet bloggers exploded on to the pages of The New York Times. Signed by respected designer Jasper Morrison, the piece, made from Douglas fir, was a replica of an old wine crate: was this design at its most truthful, or just piss-taking cynicism?

This month, the company launches its cheekiest initiative yet. To tie in with the London Design Festival, Willis is holding an exhibition – Established & Sons Elevating Design – in a vast subterranean space in Marylebone. The firm’s high-volume production pieces have been replicated in Carrara marble and will be displayed on grandiose plinths. None is for sale. The exhibition is intended to provoke a debate about so-called “Design-Art”.

“We want to position ourselves as commentators,” says Willis. “I’ve always said the company is more than just a simple manufacturing firm, and this is our first exhibition to put our cards on the table and say we believe our role is to be bold.”

When we meet at the company’s offices in Shoreditch, Willis is reeling, and not just from a condensed task list prior to a “big family holiday” on Long Island. He and McCartney are expecting their third child, due on New Year’s Day. “We always wanted several kids but this is a…” he picks his words carefully, “…a delightful shock.” Their son, Miller, is two; their daughter, Bailey, seven months. If Willis is pivotal to Established & Sons’ success, its core ethos was generated as much by two of its other founders, Sebastian Wrong and Mark Holmes. They are from diverse backgrounds. Willis’s businessman father was one of those men who could build half their house and the kitchen table they ate from. Wrong’s father, Henry, was the first director of the Barbican Centre. Holmes grew up in Grimsby where his father held down a variety of jobs, from taxi-driver to pub landlord. Each, though, trained in fine art, and they met either studying for BAs at Norwich or MAs at Slade.

Wrong and Holmes later set up a small company manufacturing their own designs. When Willis, who had risen from advertising sales to publisher of Wallpaper*, left the magazine, the three joined forces. They shared a frustration over the design brain drain from Britain. “It was a given that you had made it as a designer if B&B Italia or Cappellini came knocking at your door,” says Willis. “So we asked: can we change this?”

If they could succeed in forming a company to commission British or British-based designers and manufacture their products in Britain, there would be inherent advantages – more control, shorter lead times – as well as environmental benefits. “And yes,” says Holmes, “there’s pride involved. There was a sense of the decline of British manufacturing and we wanted to prove everybody wrong.”

Willis had been introduced to Angad Paul, head of Caparo, a manufacturing group that makes parts for everything from Aston Martin cars to Challenger tanks, by a colleague of Stella’s. Paul provided seed money and a manufacturing platform for the embryonic company. At this point, the team recruited another art-school buddy, Tamara Caspersz, who brought marketing contacts to the mix.

All five are 36, photogenic and at similar life stages: Willis, Wrong and Paul have young children; Holmes and Caspersz are both single. Paul also wears a film-producer’s hat and funded Guy Ritchie’s two best-known movies. Persuading established designers to work with an untried outfit was not out of the question, given their profile. Willis knew many through Wallpaper*. And when Stella hit her address book, she recruited the architect Amanda Levete of Future Systems.

While it can take as long as a year to develop an item of furniture, Established & Sons gave themselves just five months to produce the range they took to their first Milan Fair. Tamara Caspersz remembers a blur of 19-hour working days. But it paid off. They were the media triumph of the fair. Their designers turned out to support them, as did Stella.

The paparazzi scrambled for shots of the McCartney-Willis corps d’élite at their launch and anniversary bashes. The first was held in a Hoxton bus depot, the second in Grosvenor Place to celebrate a new red Aqua table to benefit Bono’s Red (Aids in Africa) Campaign. “Our general approach has been brash,” admits Holmes. “If we’re going to compete in an international arena we have to be as flamboyant as the Italians and as efficient as the Germans. We can’t sit shyly in a corner.”

“Some people can’t wait to see if we’ll fall flat,” Willis adds. “Noses are always shoved out of joint when you come from relatively nowhere and start getting a lot of positive attention.”

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