If your garage has been reduced to a dumping ground for anything that doesn’t fit in the house — old chairs, carpets, the rowing machine that never left the box — it could be time to make better use of it.

Garage conversions are relatively straightforward and, at £10,000 or less for a single-car structure and £20,000 for a double, more cost-effective than adding an extension or loft conversion. Turning your garage into an extra room can also be profitable. Most conversions will add more value to the house than the cost of carrying out the work.

In Bridie Davey’s case, her 1930s-built garage, partly adjoining the kitchen, was too small to accommodate a family-sized car, “so it was just a waste of space”. She hit on the idea of putting a door into the back wall and turning the garage into a utility room.

But Tom Bates of Belfast-based architectural services company, Carryduff Designs, came up with a grander plan. Why didn’t she and husband Gerry consider knocking the garage through to give them a larger kitchen as well as a utility room?

Now, instead of a “horrible” dated kitchen with tired oak units and green-coloured worktops, the Belfast couple have a roomy L-shaped kitchen, with a skylight window and adjoining utility room. The conversion cost about £20,000, and the couple splashed out a further £6,000 on a new kitchen.

Davey, a teacher in her late forties, says: “We now have a dining area, which we didn’t have room for before. The kitchen is double the size it was and I’ve also got a utility room, which takes up about one-third of what used to be the garage.”

Davey is hopeful the extra living space has added to the appeal of her detached four- bedroom house, now valued at about £450,000. “I would say we’ve got a lot more value out of it and if we ever come to sell, people go for kitchens and bathrooms.”

In the West Midlands, Simone Jones so enjoyed visiting beauty therapists that she decided to open her own salon — in the garage. The 37-year-old mother of three chose to operate her new business, Beauty Matters, from home. Her existing property wasn’t suitable, so the family moved to a three-bedroom end mews house in Solihull that had an integral single garage.

“When we were househunting we had it in mind that a garage would be ideal for conversion into a beauty salon,” says Jones.

After checking building regulations requirements, she enlisted the help of family and friends to transform the faceless garage into a smart, well-equipped treatment centre at a cost of about £10,000.

Stuart Flint of estate agent Knight Frank in Birmingham says a garage conversion can increase the value of a house by as much as 20%, but adds a note of caution: “It will add value provided that, at the upper end of the housing market, there is enough space to build a garage, either integral or detached. At the lower end of the market, you have to ensure there’s enough outside parking space.

“In some areas, such as parts of Birmingham and London where garages are at a premium because parking is a pain in the neck, it might be better to consider adding an extension rather than turning the garage into an extra room. In most cases, however, the extra space created by converting a garage outweighs the lack of a garage.”

Stephen Marriott decided to convert his detached double garage because he needed somewhere to accommodate his elderly mother-in-law.

“We live in a cottage in Buckinghamshire dating back 300 years that had been renovated and extended to include a new garage. When we found we needed to move my mother-in-law to live with us, converting the garage seemed a fairly obvious choice,” he says. “She wanted to maintain some level of independence and have her own front door.”

Marriott, a chartered surveyor, called in The Garage Conversion Company, a specialist firm based in Bedfordshire that operates across the UK. The result is a studio-type apartment with a galley kitchen and en-suite bathroom. It is likely the £20,000 cost of the conversion would be recouped if the cottage, valued at about £650,000, was sold.

Phil Bateman, managing director of The Garage Conversion Company, says: “People don’t use their garages for putting their cars in, so if they need more living space, they can either move house or, for £10,000 or less — the amount you pay in fees and moving costs — we can give them extra space by converting their garage.

“A normal single garage measures 150sq ft, which makes for a good-sized living room, bedroom or office.”

Planning permission is not usually needed, but anybody who is planning such a conversion should check with their local authority, adds Bateman.

“There are sometimes parking issues, so additional parking is sometimes required because you’re technically taking away parking space.”

A garage conversion needs to comply with building regulations, so any work has to meet current standards of insulation, electrical installation and ventilation.

Carryduff Designs, 02890 814 106, www.carryduffdesigns.co.uk; The Garage Conversion Company, 0800 587 0262, www.garageconversion.com

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