“Spite houses” — structures built or modified specifically to annoy someone — are flourishing in the United States, where private-property culture, individualism and the country’s fragmented zoning laws create ideal conditions for satisfying personal grudges through real estate.

A CNN article about the phenomenon cited Boston’s four-story Skinny House, built by a returning Civil War soldier to block his brother’s view, and more recently, the Equality House, one of two properties bought across the street from Topeka, Kansas’ Westboro Baptist Church, known for its anti-LGBTQ+ rhetoric and for picketing at soldiers’ funerals. The owner painted the homes in rainbow colors of the Pride Movement.

“Hostile architecture is very American,” said Paavo Monkkonen, UCLA Luskin professor of urban planning and public policy. “Your house represents more here than it does in other countries. It’s a more personal symbol because it’s a homeownership society. There’s more neighbor-to-neighbor conflict.”

Spite houses are a local, highly personal kind of hostile architecture, which more broadly includes things like uncomfortable park benches meant to keep homeless people from sleeping on them.

“The U.S. approach to urban design is often not people-centric, in the sense that in certain parts of the city you want to build things that no one will go to, plazas that will be empty, because you want to protect your own peace and quiet,” Monkkonen said.