Half of the buildings Americans will live, work and shop in by 2030 haven't even been built yet, according to a study done for the Brookings Institution by Arthur C. Nelson, a professor and director of graduate studies at Virginia Polytechnic Institute and State University.

Total construction needed between 2000 and 2030 to accommodate growth projections will amount to roughly 210 billion sq. ft. or 70 percent of existing built space. Much of this space will be residential, but commercial/industrial space will grow faster as a percentage of existing built space.

Much of the research focuses on the ability to literally reshape future development.

"Recent trends indicate that demand is increasing for more compact, walkable and high quality living, entertainment and work environments," Nelson writes. "The challenge for leaders is to create the right market, land use and other regulatory climates to accommodate new growth in more sustainable ways."

Highlights of the paper, "Toward A New Metropolis: The Opportunity To Rebuild America," include the following:

• By 2030, the nation will need about 427 billion sq. ft. of building to accommodate growth projection. About 82 billion sq. ft. will be from replacement of existing space and 131 billion sq. ft. will be new space.

• More than 100 billion sq. ft. of new residential space will be needed by 2030. Commercial/industrial space will account for the most new space with more than 60 percent of the space in 2030 less than 30 years old.

• Most new growth will take place in the South and West. States such as Nevada and Florida will see the most dramatic growth. The Northeast will lag compared to other parts of the country.

• The projected demand for industrial space in the Midwest outpaces other regions. Rust Belt states - Ohio, Michigan, Illinois and Indiana - will be the largest producers of industrial space after California. By 2030, 70 percent of the Midwest's industrial space will be less than 30 years old.