Stanford University has brought in two top-tier New York City architecture firms to design the $1 billion-plus Medical Center expansions, spokeswoman Shelley Hebert said recently.

Rafael Vinoly Architects will lead the Stanford Hospital project and Kohn Pedersen Fox (KPF) has been selected for the Lucile Packard Children's Hospital, Hebert said.

Vinoly has designed the University of California San Francisco Helen Diller Family Cancer Research building, which is under construction, and the Memorial Sloan-Kettering Cancer Center and Children's Hospital in New York.

KPF has designed The Children's Hospital in Philadelphia and the World Bank headquarters in Washington, D.C.

Stanford Medical Center is proposing a complex demolition/rehabilitation/construction project that would add a net 1.3 million square feet, more than 1,000 peak hour vehicle trips and nearly 2,000 jobs.

William Pedersen, the 69-year-old co-founder of KPF, said he found the project attractive for many reasons, including Palo Alto's temperate climate.

"The opportunity to do a children's hospital is a wonderful challenge for an architect," Pedersen said. "The spirit of the building needs to be very responsive to the emotional needs of the children that are in the hospital."

He said he plans to do that by concentrating on opening up the hospital to nature and Stanford's nearby arboretum. The building will have a series of terraces, courtyards and a distinctive north and south side to capture sunlight, he said.

"The climate year round is wonderful (and provides) the opportunity to create landscape in conjunction with a building," Pedersen said.

The two facilities are independent, but the architects will coordinate their designs with existing structures, Hebert said.

The selection process began in 2006 and construction is scheduled to begin in 2010, Hebert said.

Local architecture firms Lee, Burkhard, Liu, Inc. will assist with the Stanford Hospital

project, while Hammel, Green and Abrahamson, Inc. will work on the children's hospital, Hebert said.

Stanford University has begun calling the project the Renewal Project.