Warner Bros. on Tuesday officially broke ground on a pair of Frank Gehry-designed office towers, which when completed will mark a major expansion of the Burbank-based movie and TV studio’s headquarters.

Warner Bros. is calling the design and construction phases of its new effort the Second Century Project, in honor of its upcoming centennial. The deal comes amid a production boom driven by massive demand for TV and film content.

The deal is one of Burbank’s biggest real estate transactions ever, with a combined estimated value of more than $1 billion.

New Burbank Mayor Sharon Springer and Gov. Gavin Newsom touted the projected effect of the real estate project on the economy. The civic leaders said the construction is expected to generate 2.5 million hours of work.

“By definition, this is a project that shows confidence in our [California’s] future,” Newsom said. “This is a big deal, not just to Burbank, but to the entire region and the state.”

Worthe and partner Stockbridge plan to keep about 7 acres of the Burbank Studios site, where they will build the Gehry-designed office towers, which Warner Bros. will occupy as the sole tenant. The 800,000-square-foot office complex will consist of a seven-story building and a nine-story structure.