Architect Rafael Viñoly will work with OLIN Landscape Architects and the Sand Hill Property Company to transform the Vallco Shopping Mall in Cupertino into a hybrid hub of downtown-style retail and office buildings as well as hundreds of rental homes all wrapped within a man-made open space preserve.

If the plans are approved, the Hills at Vallco Scheme would occupy a 50-acre (20 hectare) site in the heart of Silicon Valley.

“The Hills at Vallco features an unprecedented 30-acre community park and nature preserve, which will not only be the largest community park in Cupertino, but also the largest green roof in the world,” said a statement from Sand Hill Property Company, the developer behind the $3 billion (£2 billion) scheme.

The undulating green roof – designed to buffer the partial residential scheme from neighbouring industrial estates – would be crossed by a 3.8-mile network of walking trails. Vineyards and orchards, an amphitheater, playgrounds and banks of native planting to attract local wildlife would also be hosted on the roof.

Up to 800 apartments, 185,000 square metres of office space and a new shopping centre containing a cinema, bowling lanes, an ice rink and gym are intended to site below the green roof.

Sand Hill director Reed Moulds said: “The Hills at Vallco expresses the lifestyle, innovation and creativity of Silicon Valley, and reinforces Cupertino’s position as the social, economic, technology and architectural centre of Silicon Valley.”

Plans for the scheme will be submitted to the City of Cupertino in the coming weeks and a public consultation is currently underway.