The Oxfordshire home of some of Britain's most valuable cars has won a top award in a prestigious architectural competition.

The Aston Martin Owners' Club's new headquarters in Drayton St Leonard, near Wallingford, shared top prize in the Royal Institute of British Architects South 2002 Conservation Award for the extension and alteration to an historic building.

Architects from the project's designers, architecture plb, of Winchester, collected the award at a ceremony at Oxford's Said Business School last night.

The team from the London partnership Jeremy Dixon Edward Jones, which designed the business school, also received an award, as did Niall McLoughlin, for his design of Oxfordshire private home the House at Jacob's Ladder.

The headquarters of the Aston Martin Owners' Club is now housed in a converted Grade II listed elm-framed barn. The outside still looks like an agricultural building, but features inside include windows controlled by remote-controlled shutters.

Club secretary John Burslem said: "It works really well. The space is large enough for visits by educational groups and for lectures on technical subjects."

It shared first prize with an extension to St Peter's Chuch, at Hayling Island.