A blue-and-gray treehouse above a small street on Capitol Hill has led to finger-pointing and the silent treatment among neighbors.

There have also been stop-work orders, permits filed with the District government and redacted emails. Ah, it is classic Washington.

“When people go into opposition on something, they’ll pull out every possible way to get at something,” said Kirsten Oldenburg, Advisory Neighborhood Commission 6B chairwoman. “People on Capitol Hill, they know how to get information. They are professionals.”

At issue is that the eight-foot-high treehouse juts into public space by about 20 inches. It looks like a castle and is perched in a 100-year-old elm tree on a U-shaped alley called Archibald Walk. The narrow street, near G and Sixth in Southeast, is lined with a half-dozen homes.

Many of the homes on Archibald Walk don’t have traditional front or back yards, and neighbors say the alley has become a public, shared space. It has been lined with flowerpots and benches, and a wedding was once held in the spot beneath the now-controversial treehouse. But the treehouse appears to be the one thing some neighbors don’t want to share.

This Capitol Hill treehouse has sparked debate among neighbors, with some saying it shouldn't have been constructed over public property. The green line on the ground is where DDOT says the homeowners' property line ends. (Larry Janezich/ Capitol Hill Corner )

The neighborhood blog Capitol Hill Corner first reported on the structure that has managed to divide the neighborhood.

One commenter, Brian C., wrote on the blog: “People who oppose tree houses never had, nor ever will have, any quality of life.” Another, identifying as RD, wrote: “It’s a treehouse. Relax people.”

But opponents say the treehouse “overwhelms” the public space.

To hear homeowners Ellen Psychas and Bing Yee tell it, it started out simply enough. Psychas, who counsels high school students about college, and Yee, a Department of Homeland Security lawyer, wanted to build a princesslike treehouse for their two daughters, ages 3 and 5.

They said they checked with city transportation officials and the District’s Department of Consumer and Regulatory Affairs and found there were no specific regulations regarding the building of small treehouses.

The couple said they passed out fliers alerting neighbors that they were building it and got no response. They also hired an arborist to help them avoid harming the tree, then bought $300 worth of “eco-friendly tree-building hardware.”

[Father battles Fairfax zoning laws for sons’ treehouse]

They built the nearly 30-square-foot treehouse. But now city officials say they didn’t have the proper permits.

Loraine Heckenberg, who lives nearby, said she and other neighbors on the street think the treehouse “overwhelms the public space.” She is also concerned about the lack of permitting and code enforcement when the structure was built.

Heckenberg said she has spent as many as 20 hours a week in an effort to have the treehouse removed from the public portion of the alley. She has filed Freedom of Information Act requests with city agencies to learn more about the permitting process.

Heckenberg said the owners of the treehouse used to play occasionally with her rescue dog, but they no longer speak.

“I don’t feel a need to necessarily upset anyone,” she said. “But the rules are the rules.”

For the couple who built the treehouse, it’s gotten to be a bit too much.

“I don’t like the way this has escalated,” Psychas said. “We’re surrounded by grumpy old retired people. People don’t have kids.”

But, she noted, “it’s Washington.” She and her husband have lived on Capitol Hill for 30 years and have owned the house since 2011.

“We’re not new to the area,” Psychas said. “We’re just concerned about this level of spitefulness.”

ANC representative Jim Loots called Archibald Walk a “treasured, historic enclave.”

“Had the property owners built their structure on private property, we would not be having this discussion,” Loots said. “This is public space in the truest sense of that term, and a private treehouse is simply not an appropriate use of that public resource.”

Still, some say, the treehouse is charming.

“In my personal opinion, it’s rather cute,” said Oldenburg, the ANC chairwoman. “I understand that the people who live there have different views of what their alley should be.”

She said she believes the owners did “due diligence” in researching the permitting process for the structure but “got caught up in a mess of bureaucracies.”

Matthew Marcou, an associate director for public space regulation administration at the District Department of Transportation, said the couple should have obtained permits, and a review should have been done before the city’s public space committee before the treehouse was built.

Yee and Psychas said the city had no clear rules on treehouses to guide them through the process.

“We did, in fact, try to obtain permits,” Yee said.

The city issued a balcony permit in November after an inspector looked at the property — several months after it was built. City officials now say a review was needed for a permit to allow the structure into public space instead.

Will the treehouse be torn down? That could depend on the outcome of a public hearing scheduled for Jan. 28.

Heckenberg, who said she has spent months dealing with the issue, said she hopes for a resolution soon.

“I hope it gets taken down and we can go back to healing,” she said.

Magda Jean-Louis contributed to this report.