Although the project shocked many who expected a smaller renovation, contractors say scope changes are far from rare on historic renovation projects.

“When you’re working on a historic restoration, it’s almost inevitable you will encounter surprises once you begin opening walls,” said Ralph Esposito, national president at Suffolk. “These structures often have undocumented changes, outdated material or hidden conditions that only reveal themselves once that work begins.”

Esposito encountered this during Suffolk’s renovation of the Waldorf Astoria in New York City. As with many historic buildings, original drawings didn’t always match reality. One beam listed as a foot wide in the plans turned out to be three feet wide, Esposito said.

At the White House in September, Bethesda, Maryland-based Clark said it expected to finish the build before the end of Trump’s second term in 2029. That timeline raised concerns from some that the project was moving too quickly and without sufficient oversight.