Acanthus Lawrence & Wrightson Architects has unveiled its competition- winning design for a virtually new London Underground station at Hounslow East on the Piccadilly line. The scheme - which includes a new ticket hall, interchange passageway, stairs and lifts - is based on a timber diagrid deck. Diagonal ribs are supported on structural 'trees' rising from street level, and the roof is clad in green patinated copper shingles. The building has a transparent elevation to the main road. Completion is due in summer 2000.