Barn conversions can be highly controversial. To planners and pre-servationists alike it is heresy to insert windows in blank walls and skylights in grand sweeping roofs. To succeed, barn conversions must be extremely good.

Brockhurst Barn, on sale with Harrods Estates for £1,395,000, was bought five years ago by Simon and Gina Brockhurst-Souter in a decayed state. But it was much-loved and regularly used by locals for barn dances and exhibitions. It stands in the centre of the village of Washington on the edge of the South Downs. “You can ride into the hills without crossing a road,” says Gina.

It is part of a tight cluster of buildings around an ancient Sussex church. A fine Regency rectory stands next door. Church Farm and its two hip-roofed barns are just across the road. Church Farm Barn has been renamed Brockhurst Barn, the name announced on smart lettering on the wall beside the grand new entrance gates, built of stone found on the site, says Gina. The drive swings round showing off the glorious view ending in a gravel sweep, flanked by a new oak garage, a trio of stables and an immaculate golf green with twin putting holes.

The green is the reason for the move so soon after the conversion was completed. The Brockhurst-Souter’s younger son is such an ace on the golf course that they are thinking of moving to Florida to support the next stage of his career.

The barn has been dated to the early 1400s by Annabel Hughes, who has written a masterly book on the subject. She points out that typical barns have, as here, one high entrance for the cart to enter full of hay and a low one on the other side to exit empty without turning. This is the obvious place to put the windows.Internally, this means the interior can become one great hall rising to the rafters. It’s 70ft long — that’s five bays, or four sets of trusses: the names given to each set of posts, tie beams and crown posts that support the roof.

Simon Brockhurst-Souter, who masterminded the conversion himself, left the roof open for the full length but introduced a partial cross wall at ground-floor level to create a 25ft-long kitchen. Gina, an ardent cook, says: “He left an opening through to the barn door windows so I would always have daylight when cooking. We took the whole roof off and sandblasted all the oak”. Where joints had rotted, new wood was “scarfed” on to the old and all the timber now has the pale fresh colour of young wood, though its venerable age is everywhere apparent.

A great hall calls for a roaring log fire. Building regulations, says Gina, would not permit an open fire in a timber building. So though there is an impressive chimneystack built of recycled brick, it houses a gas stove.

The making of the interior is the superb quality of the materials. The front door is as solid as a 16th-century one, of kiln-dried oak complete with iron studs. Bedroom and bathroom doors are of oak, as graceful as in a house by the Arts and Crafts architect Charles Voysey. With them come polished limestones and marbles, supplied through Simon’s business, LBS Enterprises Ltd, which specialises in natural stone.

Over the kitchen a spacious gallery serves as a study. The bedrooms are set in two former stable wings, opening at right angles off the barn and looking out on to a newly created fountain court. One wing has bedrooms for three sons, each with its own shower room.

“Boys don’t do curtains,” says Gina. Instead they have a glazed door overset with a full-length Venetian blind that lifts off and clips back into place with the help of a series of magnets.

The master bedroom suite is in the west wing, with one of the smartest modern bathrooms I have seen. “I wanted the effect of a spa,” says Gina. The bathroom is floored and panelled (to dado height) in polished limestone and dark walnut.

Minimalist it may be, but there is an Ancient Roman luxury in the broadness of surrounds to twin basins and central bath.

As you emerge on the expanse of lawn to the south, the tower of the church comes into view. The one drawback is that the A24 passes close by. It’s in a ravine, but you can hear the traffic. For those who want a quick sprint to London, the dual carriageway is five minutes away, with as open a road as you can hope to find in southeast England. Toad would have loved it.

Fast facts

Where is it? Washington, West Sussex, 11 miles from Horsham, 29 miles from Gatwick and 51 miles from London.

How much is it? £1,395,000 What you get A converted barn with great hall rising to the rafters, fouren suite bedrooms and 4.6 acres.

Agent Harrods Estates (020-7409 9001, harrodsestates.com)

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