The property had been chopped up into flats in the Eighties, but after three years it is now an impressive townhouse with a kitchen-diner, utility room, home cinema and loo on the lower-ground floor. On the ground floor is a living room and on the first floor there are two guest bedrooms and a bathroom. The top floor has a master bedroom suite, with an office area and roof terrace on the mezzanine above.
"I didn't just want a house," says Mark. "The more important thing was to create a place that my friends would enjoy as much as I do." The appeal of the "pretty hideous" house he spotted in 2009 was its small back garden and the way the light entered the building.
He wanted an invisible boundary between the interior and exterior and imagined a skylight bringing light from the ground floor to a basement kitchen. "I had big ideas with no idea of how to make them happen," he says.
But architect Gianni Botsford did. He suggested a two-storey extension at the back of the house with a double-height light well and also the conversion of the top floor into a bedroom suite with a cool spiral staircase leading to an office and roof terrace.
There were a few luxurious extras, too. "It was always my dream to have a freestanding bath in my bedroom — I see it as 'house art'," laughs Mark, "though it's definitely not form over function."
The lower-ground floor is where the cooking, drinking, talking, relaxing, listening to music or watching a film happens. There's a courtyard with a seating area at the rear and a party-size home cinema room at the front.
Upstairs on the ground floor is a huge, comfy living room that almost doubles as an art gallery. "Most of the art I buy has a twist. Not everyone would like it, but it makes me smile," says Mark.
His home is all about clever mixing: traditional with contemporary; classic design with kicks of kitsch; the inside with the outside; the blurring of the lines between living, eating and relaxing.
"My love of entertaining and making sure people have a good time is paramount," says Mark. "I've never wanted my home to be just about style but it was very challenging. I am a perfectionist, so I'm every architect and builder's nightmare — but somehow we've all remained friends."
A favourite designer is Jimmie Martin and Mark even had a go at creating his own Jimmie Martin-inspired graffiti painted side table. "They told me not to give up the day job," he laughs. "It's actually much harder than it looks."
* See architect Gianni Botsford's work at giannibotsford.com
Photographs: Alexander James
Styling: Mary Weaver