Michael Wilson belongs to the select band of entrepreneurs who bring back grand country houses from years of institutional use and make them appealing homes once again. His prime stalking ground has been Surrey and Sussex; now he is looking west to Somerset and is nearing completion of several major projects.

The question with country-house conversions is whether they go with the grain of the architecture, making the most of a building’s intrinsic qualities, or simply cram in the maximum number of living units.

One of Wilson’s projects is Snowdenham Hall, near Godalming, Surrey, built for the Courage family in 1885. The architect was J.F. Bentley, designer of the Roman Catholic cathedral at Westminster. Here Bentley shows himself a master of large-scale composition, with black-and-white and tile-hung gables and soaring chimneys.

The conversion works well. Wilson has tackled the great height of the building by creating duplexes, the lower ones occupying the ground floor with bedroom windows opening to a garden arcade below. The upper ones have bedrooms beneath the eaves with fine views.

The flats share the splendid Great Hall which, unusually, is entered from the end rather than the side. A soaring oriel window fills the far end, with row on row of heraldic stained glass. While working on the interior, Wilson discovered William Morris-style wall paintings with a swirling pattern of pomegranates.

A second project is St Joseph’s Abbey, another former religious retreat just by the church in Storrington, West Sussex. Here a 17th-century rectory was bought in 1911 by an antiques collector by the name of Bethell, who introduced a Queen Anne-style oak staircase. Most rooms are panelled. In the 1920s a new owner added a ballroom and music room. “

The house splits very neatly into periods, each becoming a separate house,” says Wilson. In one new home, the former chapel with wagon-shaped plaster ceiling has been converted into a kitchen and dining room. The only external change has been the insertion of a new front door, leading to a rooftop penthouse that he has created over the ballroom. All the main rooms retain original lead glazing, each to a different ornamental pattern. The new houses overlook lawns, and the more formal parts of the garden by the house are assigned to individual residents, so that no one walks in front of a neighbour’s window.

One big challenge with conversions, Wilson explains, lies in introducing new plumbing without damaging historic interiors or being heard through the new party walls. He used cast-iron pipes at St Joseph’s to ensure that the plumbing was silent. He says: “There is strong demand for these conversions, but problems arise when people can’t sell the houses they’re moving out of. So now we look at their houses and weigh up the potential for improvement, or for selling off a small plot of land. If it works, we take on the house, enabling our purchasers to complete.”

A four-storey house in the main range at St Joseph’s is available for £1.1 million and a penthouse flat with a roof terrace for £600,000. At Bradstone Brook, near Guildford, a pretty Georgian house with numerous extensions, he is offering a Victorian wing for £975,000. At Badgeworth Court in Somerset, a Georgian house with Victorian additions, he is offering conversions ranging from £500,000 for two bedrooms to £850,000 for four bedrooms.

A further project, Chew Magna Manor, near Bristol, has been more of a problem. Here a primary school was renting a modern building in the grounds that intruded on views from the house. Wilson offered the school a new freehold site out of view of the house, but the planners would not agree to internal division of the house and it will soon go on sale as a single residence at £2.75 million.

As an architect and developer who markets his conversions through his own company, Wilson is an unusual bird. He says proudly: “I am still best friends with my first purchaser.”

Michael Wilson Restorations, 01483 271733, www.mwrestorations.co.uk

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