For the past three years, Virginia drivers have paid extra attention while navigating confusing work zones on the Capital Beltway. But lately, the highway has managed to serve up another distraction: a single-family house poking awkwardly through a sound wall.

The bizarre sight has left gawking motorists wondering: Who could possibly live there? The answer: no one. The four-bedroom house is owned by the Virginia Department of Transportation, which purchased it for $650,000, according to Fairfax County tax records.

The sale was part of several real estate acquisitions needed to make room for the $1.4 billion high-occupancy toll lanes project, which involves adding four lanes to the Beltway along a 14-mile-stretch between the Springfield interchange and the Dulles Toll Road.

The home in Annandale backs up to the southbound lanes of the Beltway near the Gallows Road overpass. What sticks through a 20-foot gap in the sound wall is actually an addition to the house — an expanded kitchen with burgundy window shutters.

The house is on Luttrell Road, a residential street that parallels the Beltway. VDOT purchased all of the houses — a total of eight — along the east side of Luttrell. They were acquired in 2009 and 2010 through private negotiations with the owners, project officials said.

Some of the houses were briefly used to conduct training exercises for the Fairfax fire department. Six have since been demolished.

The properties were the only residences acquired for the entire HOT lanes project, said Jaime Breme, a project spokeswoman.

They were needed to make room for an on-ramp from Gallows Road to the southbound lanes of the Beltway.

“That ramp had to be realigned, and that’s why those homes had to be taken,” said Jeff Wagner, a spokesman for Fluor-Lane, a project contractor.

The two houses still standing, including the one poking through the sound wall, are being used as field offices for Fluor-Lane workers. There, crews evaluate concrete mixtures used to build new piers, overpasses and bridge decks, Wagner said.

The properties will be demolished by the time the project is completed in late 2012, project officials said. The land will be planted with trees and other vegetation.