Nearly all of the office buildings in North Jersey were built during a 1980s construction boom, and they are therefore roughly the same age. But they have vastly different life expectancies.

Some have been given up for dead and are scheduled for demolition.

Others are past their prime and sit unloved and empty.

But a growing number have been reborn, with head-to-toe renovations designed to please a new generation of workers.

Millennials, and the employers seeking to attract them, want office environments with an urban feel, even if that means creating a mini-downtown within a bland suburban office park by adding such amenities as walkways, restaurants and housing.

In their evolution from the 1980s, the office buildings that “can create that exciting type of environment in the suburbs will be the winners,” said Rutgers Professor James Hughes, dean emeritus of the Edward J. Bloustein School of Planning and Public Policy and an expert on demographics and economic trends.

Along with those winners, “there will be a lot of losers that just come down,” said Hughes, who during his career has tracked the rise and decline of New Jersey’s office parks and their impact on the state’s suburbs.

Office buildings colonized the North Jersey suburbs in the last decades of the 20th century. Now, changing demographics and seismic shifts in the way we work are reshaping those aging corporate parks.

At the moment, fueled by a robust economy, older office buildings are proving more resilient than previously predicted, with a number of formerly vacant corporate campuses getting a new lease on life.

In Essex County, for instance, a striking, zigzag-shaped glass building built in 1982 in Roseland as a corporate palace for Prudential, and later home to a succession of pharmaceutical companies, now houses two law firms and other tenants who wanted corporate campus amenities without the cost of a corporate headquarters building.

At the site of the former Hoffmann-La Roche headquarters, a 116-acre campus that spans the border between Clifton and Nutley, predictions that the site would sit vacant for a decade have proved wrong. In the two years since the site was sold, Hackensack University Medical School at Seton Hall University has moved in, along with the Seton Hall School of Nursing and College of Medical Sciences, three bio-tech research firms and fashion company Ralph Lauren.

“Everybody told us it would probably take 10 years-plus to develop this site,” said Ed Cohen of Prism Capital Partners, the developer of the site, now called ON3. It now looks as if the site could be fully developed in five to seven years.