This was a good thing because, although I had to trust he wouldn’t do something too trendy that might date, I was also happy in the knowledge that no matter how wild he took it, it couldn’t be as bad as if I had decorated it myself.

At one point, I briefly considered sticking a huge contraption on the front of the place, like the one Steve Coogan’s character Phileas Fogg has in Around the World in 80 Days. Then there’s the ever-present desire to spend thousands of pounds on old Sex Pistols artwork at TomTom, just off Shaftesbury Avenue.

What Lait did was make me feel like I could invite friends over with that “my parents are away” feeling, that sense of wonder you get as a teenager the first time you get the run of the family home.

And, as he said, the process was fairly simple. No builders were involved.

He drew up mood and storyboards for each room, with a floorplan and swatches and colours for furniture, fabrics and walls. The divorce had cleaned me out, so I had fixed the budget at what it would have cost in fees if I had bought a new place. In a way, it felt like I was changing the house while saving money.

Out went fixtures and fittings that were there when we bought the place; in came enough colour to give it the feel of a home designed by Paul Smith.

As soon as you walk into the entrance hall, you come across a multicoloured linear mirror, a 1930s style Archivio Storico lamp and a console table. Linking the top three floors is a stair runner that my ex-wife scoffed at on her first return (a bonus), friends asked me for its name (another bonus) and, most importantly, my son immediately crawled down like a crocodile (jackpot).

“We want your bedroom to be a bit more male, but not overtly so,” Lait explained, as he optimistically added a few touches that suggested a regular girlfriend would eventually appear. New cotton drill curtains, 1970s-style wallpaper, a black shell chandelier and stylish side tables and lamps, and a Costes chair by Philippe Starck gave my room the look of a cool boutique hotel.

In the living room, Lait came in with what for a while I called my Big Gay wallpaper: imagine a pop-art version of Tony Montana’s bathroom in Scarface. He covered only the chimney breasts with it; we mounted a plasma screen on one and he stopped me putting a Get Carter poster on the other.

We selected a corner sofa by Seven Salotti and placed an enormous floor lamp like you see on film sets in the corner. Lait also sourced decorative door and cupboard handles that give a nice touch of detail. On and on it went, a chain of boxes and couriers containing well-designed kit that made every knock on the door seem like Christmas.

The colour and the lighting have indeed washed away the misery of the previous years and given me and my son a playground of our own choosing. My biggest challenge now is keeping my large dog off the furniture.

The best thing is that it all cost less than I would have paid in estate agent’s fees and stamp duty for a new house.

The redesign was liberating. Perhaps the greatest indication of its success is that the only person who doesn’t have a good thing to say about my wallpaper, my carpets and everything else in the house is my ex-wife. It’s a year since we went our separate ways, and at the moment she’s in the middle of builders’ hell. Director Phil John is staying herewhile shooting the new Irvine Welsh film for Channel 4, so the house rarely feels empty and, most importantly, it has the feel of somewhere fun and new.

At a time when everything else is shifting dramatically, changing your decor and not your location can give you a new sense of freedom. But right now I’d better get out the back. I need to decide where to stick the diving board.

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