Most couples with a new baby and a small flat look for a bigger home. Nothing so obvious occurred to former Heaven 17 singer Glenn Gregory. When he realised his imminent offspring would have to be lodged in his recording studio, also known as the flat’s second bedroom, he simply ordered another room to be parked in the garden — for the studio, not the baby.

There was no question of moving. Gregory and his wife, Lindsay, a make-up artist and graphic designer, were prepared to put up with months of building hassle just for the privilege of staying exactly where they were in Primrose Hill.

If it wasn’t for Billy, their whippet, they would not have the flat at all. Ten years ago, when they were renting in Twickenham, west London, they would take Billy for walks on Primrose Hill. “We were having a sandwich in the car when we noticed a flat to rent,” says Gregory. They moved in not long afterwards. “Then, after three years, the nice lady we were renting from said she was going to sell the house.”

She let them buy their flat. “It was a bargain even then, seven years ago,” he says. “We paid £140,000 and it’s now been valued at about £500,000. Sam Mendes, the director, has a similar one, with no garden, and that’s on the market for £599,500.”

Gregory does not begrudge the new baby, Louie Earl, the bedroom. He has moved his work into the garden, into a purpose-built studio that was craned in, ready to plug in and go. “I’m banished to a shed,” he says. “But it’ll help because sometimes I start work at nine and I’m still in my dressing gown in the evening. At least now I have to get dressed.”

The flat, which has a 28ft by 19ft living room with French windows looking out over the garden and park, has been given a makeover in honour of the baby. There’s a new kitchen, the bedroom cupboards have been replaced with floor-to-ceiling wardrobes, and smart oak blinds adorn the windows. A new bathroom is in the pipeline. The Gregorys, who have spent about £25,000 on the renovation, stayed with a friend while the work was carried out.

Gregory achieved stardom in the 1980s when he joined Heaven 17, the band that split away from The Human League. They had a series of hit singles, including Temptation and Come Live With Me, before fading from the public gaze. Now he’s the man responsible, with his writing partner, Keith Lowndes, for the soundtracks to television programmes Property Ladder, House to Home and Other People’s Houses.

Now, calling themselves Honeyroot, they have produced Sound Echo Location, a “listenable album,” he claims, “that you can put on and leave on until it’s finished, which is rare these days”.

The new studio, which is 12ft by 10ft and has insulation, heating, electricity and a wooden floor, cost £11,500 from Garden Studios. “They are made to building regulation standards,” says Mary Partridge who, with her husband Ian, runs the company from a converted barn in the Vale of Belvoir, Leicestershire. “They are overkill on insulation, so even on a cold day you only need the radiator for a short while.”

Ian was a housebuilder for 25 years before being inspired to copy the mountain lodges he saw while trekking through the Polish alps. A neighbour saw the result, wanted one, and soon Ian had a new business. Ten years on, all their studios are handmade to order. “We did one for a holistic healer who wanted crystals set at particular points in the floor. And an interior designer ordered one painted shocking pink,” says Mary.

There are not many places the Partridges can’t reach with a lorry and a large crane. Restrictions tend to be legal, but as long as your house is not listed or in a conservation area, and the studio will not take up more than 50% of your garden or stand less than 5m from the main dwelling, you should be okay.

Demand comes mainly from people like the Gregories: expanding families who need another room and don’t want to move. “The good thing is you can crane it out again and take it with you,” says Gregory. Not that he’s going anywhere.

Sound Echo Location by Honeyroot is available from www.justmusic.co.uk, 020 8780 5129; Garden Studios, 01949 860 482, www.garden-studios.com

Explore Property

• Buying & Selling

• New Homes

• Overseas

• Interiors

• Investment

• Gardens

• Cool In Your Code

• Specials

• First-time buyer

Times recommends

• Second homes: credit crunch casualty or money-spinner?
• How I built my own sliding house
• Top 10 incentives for house buyers