How do you turn a tired Victorian schoolhouse into a comfortable family home? Love it, live in it, then alter it to suit your needs, say Lachlan and Harriet Campbell – who, in the past three years, have transformed the Grade II-listed Old School House, in Melbury Abbas, Dorset, from a dated property with a municipal air and a warren of poky rooms into a light-filled four-bedroom house for themselves, their children and Harriet’s mail-order business.

The Campbells bought the property, a couple of miles from Shaftesbury, in 2002 for £250,000, after deciding to make the move from London. “We saw it and instantly wanted it,” says Harriet, 46. They knew what they wanted to do to it, too. “As we went back in the car, my husband [who owns a building company] drew in marker pen over the floor plan details of exactly what he wanted to do.”

Wisely, they moved in with their children, Archie, now 17, Georgia, 12, and Ivo, 10, before knocking down any walls. “You’ve got to live in a place for a bit to be inspired and get a feel for what you want to do,” says Lachlan, 49.

Nevertheless, they soon got stuck in, replacing one of the first-floor bedrooms with a bathroom. The couple also wanted to get rid of the institutional feel that lingered about the property – next to go was the clutter of small pantries and storage rooms at one end of the small kitchen, including a 3ft door to the playground, on which Lachlan kept banging his head. The Campbells also raised the roofline at the back of the house and extended the kitchen up and out, making a light, airy room with space for eating.

Their next target was an ugly, single-storey extension containing two bedrooms, which had been added to the east wing of the house in the 1960s, at a time when the practical was more important than the aesthetic. The Campbells built an upper storey onto this, creating an extra bedroom and bathroom, and rerendered the whole exterior using local stone.

Overall, the couple have spent about £100,000 on the property, which is now on the market for £750,000. But for its name, and the high windows in the vaulted drawing room (designed to stop daydreaming pupils from looking out of the window), you would not know that this was once the site of the daily grind of reading, writing and ’rithmetic.

“There’s always something rather municipal about a school, but we’ve gone as far as we can from bland school rooms,” says Lachlan. Even though the couple intend to move on to another project, he observes that the secret of a successful restoration is to create a home you would want to live in. “When you buy a property, you’ve got to change it into what you want,” he explains. “Otherwise, you’re just living in someone else’s house.”

The Old School House is for sale for £750,000 through Jackson-Stops & Staff; 01747 850858, www.jackson-stops.co.uk

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