Under £1m: Aston Martin Owners Club - Auto barn

It is a safe bet that one new use for an endangered medieval tithe barn never dreamed of by English Heritage is a sports-car owners’ club. The same goes for nearly all the members of the Aston Martin Owners Club, who had in mind a move to a modern building.

The one club member who had the imagination to make the connection between historic building and modern use was John Browning. When not buffing the chrome on his beloved car, Browning is senior director of Architecture plb, a Winchester architect with a reputation for modern building design and historic conservation.

On behalf of his club, Browning scoured English Heritage’s register of important historic buildings at risk and picked a dilapidated tithe barn, listed grade II* and located in the village of Drayton St Leonard, six miles south-east of Oxford. Restoration of the 400 m² barn is due for completion this month. The next phase will be to convert it to club premises, for which Architecture plb has obtained planning and listed building approvals. Total construction costs are estimated at £500 000.

The design is a blend of historic conservation and modern intervention that is stylish enough to appeal to the most famous of Aston Martin owners, James Bond. “In the 14th century, the barn was at the cutting edge of building technology. So, any new bits we will be adding will be modern and of their time,” says Browning.

Architecture plb has abided by English Heritage’s request not to divide the open, cathedral-like interior of the barn, with its lofty central nave, two side aisles and hefty elm timbers, which are fully exposed to view. Accordingly, the architect plans to insert just one new enclosure. Earmarked as the club office, this will take the form of a modern pod of fairfaced concrete blockwork sitting loosely at one end of the central nave and occupying only two of its six bays.

The other new accommodation will sit openly in the main volume of the barn. A few classic cars will stand on the floor and the archive store will occupy an open mezzanine deck above the office pod. As for the club’s prized trophy collection, this is to be displayed in a double-storey-height glass cabinet. Around it spirals a minimalist staircase with open sandblasted-glass treads and clear-glass balustrading that leads to an archive deck.

Certain key elements have been left out of this loose-fit conversion. They comprise the “wet” and highly serviced functions of kitchen, dining rooms, toilets, boiler rooms and cleaner’s store, which could have caused most physical disruption to the barn. Instead, these elements have been housed in another modern pod that will sit outside and distinct from the barn but be linked to it by a short, inconspicuous glazed passage.

Separation from the barn has given the external pod the freedom to assume a modern shape – an ellipse with glazed ends that is, in Browning’s words, “not trying to ape the appearance of the barn”. The only concession to its more venerable neighbour is timber-frame construction and cladding.

Restoration of the fabric of the barn entailed repairs to the elm frame, rebuilding of the perimeter walls and replacement of 70% of the handmade red clay roof tiles. Despite its 650-year age, the elm frame was largely sound. Where rot had occurred from leaks in the roof and gutters, new timber was spliced in using dowels, exactly as medieval carpenters would have done. Because of the shortage of English elm, timber was replaced in green English oak.

The original brick plinth walls around the perimeter had settled and were rebuilt on new foundations. The original elm board cladding above the plinths had been largely replaced in pine over the centuries and so was almost entirely replaced in seasoned oak boarding during the restoration. At the same time, new doors and windows were fitted into the external walls, all fitted with shutters to safeguard the building when not occupied.

The sweeping double-pitched and hipped roof will remain free of modern rooflights. This in itself will set this novel and imaginative conversion apart from the upmarket house conversions that have befallen most of the country’s remaining historic barns.