Sol Campbell has had quite a month. Only five weeks after starting a four-year deal at Notts County, the former Arsenal and England defender has quit, apparently by mutual consent. It’s not such a big commute from London, but the fact that he and his interior designer fiancée, Fiona Barratt, have put so much time into building a home together may have been a factor. “I’d love to think he left because of the house, but it’s more complicated than that,” Barratt says. “He got upset that I was here and he was in Nottingham, and we only got one day a week together. It was very tough for both of us.” To be fair, he owns the sort of house that is worth giving up stuff for.

Judging by OK! magazine, most footballers’ homes are shrines to bad taste, from the five-car garage to the gold taps on the rooftop hot tub. But Campbell has never been a typical footballer. So, instead of a Barratt mansion on steroids, his gaff is a grand 18th-century town house in Chelsea. It has been done up in impeccable 21st-century style by Barratt (who is, ironically, the granddaughter of the founder of Barratt Homes). Her taste is subtle, contemporary and distinctly upmarket. She studied at Chelsea College of Art, then at Parsons School of Design, in New York, and spent three years working with Kelly Hoppen, rising to be head of interior design, before leaving to set up her own company in 2006.

This subject is a slightly touchy one, since Campbell, 35, previously dated Hoppen, and had asked her to do some work on the house, which he has owned for five years, before falling for Barratt and handing over both his heart and the design commission.

So, was Hoppen annoyed? Barratt, 29, shrugs. “She has plenty of other work,” she says. As for the final look of the house: “It has nothing to do with Kelly,” she says firmly. “This is the way I’ve always designed, although it’s definitely the hardest project I’ve ever done, because of being personally involved.” She is also at pains to point out that she and Campbell met for the first time a full 11 years ago, on a beach in Barbados, where she was holidaying with her family. He never forgot it. “I thought, ‘Wow! Here’s an interesting one,’” he says.

Indeed, Barratt is perhaps as unexpected a choice for a footballer as the house. There’s nothing remotely Wag about her, apart from the pretty face and tawny locks. “I hate shopping,” she says, “and I hate being at the hairdresser’s. I don’t have the time — I have too many meetings.” She is too busy, in fact, doing up homes for clients such as Sir Richard Branson, which occupies her six days a week.

When they have any free time, the couple enjoy having friends over, including, occasionally, their next-door neighbour Terry Venables. You can see why: the house is a perfect entertaining space. Walk through the narrow period entrance hall and you find yourself looking down on a spectacular double-height kitchen/dining room. The ceiling space is almost entirely filled by a giant, three-tiered chandelier with a 7ft drop, which Barratt designed to hang over the Japanese elm dining table.

It’s only one example of the attention to detail she has given the project. As Campbell admits: “I’m not quite sure what I would have ended up with if it weren’t for Fiona. She’s been the driving force and I’m 100% happy with the way it’s all turned out. Well, 99.99% — the jury’s still out on the nude painting in the lounge.”

Nearby is Campbell’s study, subtly masculine with its grey silk curtains and shagreen panelling. Here he co-ordinates his charity, Kids Go Live, which takes children from ­inner-city schools to a wide variety of sporting events, with the aim of encouraging them to take an interest. “I think there is a lot of wasted talent out there. After all, sport isn’t just about athletics and football. It would be great if we could open tennis up to kids from all backgrounds.”

The study is also where he keeps some of his collection of objects — every item in the house, except for the bedroom furniture, came from the couple’s single lives. On the bookshelves are several antique cameras, some Lalique glass, and a modest clutch of football trophies and memorabilia. The rest is in storage. “We’re going to put a lot of it in the country,” says Barratt. Last year, the couple bought a manor house in Northumberland, with stables, a lake and three cottages. It’s here that they are hoping to hold their wedding reception next July, and where Barratt would like to bring up their children (she wants four, she says).

Campbell’s ­fav­ourite space is not the study, though, but the glass-walled bedroom at the top of the house. “The view is amazing. On one side, there’s the gardens, and you can lie in bed of a night and see the Albert Bridge poking up with its lights on. You feel like you’re up in the clouds.”

Having survived this first project, Campbell and Barratt are now thinking of going into property development together. “We have exactly the same taste, and Sol loves architecture,” says Barratt. “We sometimes drive around London together looking for buildings to develop.” Clearly a whole new area of stardom beckons for both of them when Campbell finally hangs up his studs.

www.fionabarrattinteriors.com. For more information on Campbell’s Kids Go Live campaign, visit kidsgolive.com

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