The commission vote marks a second federal review of an addition that, at nearly twice the size of the main White House itself, has drawn opposition from preservationists, architects, and thousands of members of the public. A federal judge last week rejected a bid to temporarily halt construction; the National Trust said it plans to file an amended lawsuit.

An architect on the board of the National Trust for Historic Preservation said Wednesday that President Donald Trump’s proposed White House ballroom is significantly oversized and should be scaled back, warning the project could permanently alter the nation’s most recognizable historic landmark.

David Scott Parker, a Fellow of the American Institute of Architects with more than 35 years of experience, shared his assessment with the Associated Press as the National Capital Planning Commission prepared to meet Thursday to vote on whether to approve the 90,000-square-foot (8,361-square-meter) project. A separate federal panel, the U.S. Commission of Fine Arts, approved the project at its February meeting.

“Everything here feels inflated,” Parker said. “The net effect of this is to adversely impact what is the most important historic — the most identifiable historic — house in the entire United States. This is permanent, what it will do to the White House.”

Ballroom dimensions exceed industry standard, architect says

The ballroom itself spans approximately 22,000 square feet (2,043 square meters) of the total project footprint. Parker said that is far larger than needed for the 1,000 guests Trump has said the ballroom would accommodate. The industry standard for ballroom events allots 15 square feet (1.4 square meters) per person, he said, which puts the appropriate capacity at no more than 15,000 square feet — roughly 47 percent smaller than the proposed design.

The proposal also includes a 4,000-square-foot (372-square-meter) south-facing porch and staircase. Parker said those elements are unnecessary because they provide no direct guest access to the building’s interior and do not comply with the Americans with Disabilities Act. The White House said Wednesday the ballroom will comply with the ADA but did not address Parker’s other criticisms.

At 90,000 square feet, the addition would be nearly twice the size of the main White House itself, which spans 55,000 square feet (5,110 square meters). Critics have argued since the project’s announcement that an addition of that scale would overwhelm the mansion and disrupt the visual symmetry of the complex.

Sight line and founding-era design at issue

Parker said his other primary concern is the addition’s effect on a sight line that Pierre L’Enfant — the French-American engineer hired by George Washington to lay out the U.S. capital — deliberately established between the White House and the Capitol along Pennsylvania Avenue.

“It’s hard to fathom that one addition could have so many adverse impacts, symbolically, architecturally and historically,” Parker said. “This literally violates the Founding Fathers’ intentions.”

Trump announced the ballroom project last summer, citing the need for space beyond a tent on the White House lawn to entertain important guests. He demolished the East Wing in October 2025 with little warning; underground construction to prepare the site has been underway since then. White House officials said above-ground construction would not begin before April 2026 at the earliest.

The National Trust for Historic Preservation, a private, nonprofit group, sought a temporary halt to construction in federal court, arguing that the White House had not submitted plans to both federal panels and to Congress for approval, and had not allowed the public to comment. U.S. District Judge Richard Leon rejected the request last week. The Trust said it plans to file an amended lawsuit.

Parker is among more than 100 people registered to speak at Thursday’s commission meeting, which was scheduled to be conducted online. Thousands of people submitted written comments in advance; many were opposed to the project.