
Photo by Julianne Tripp
What: An underground home
Where: 1107 Hillside Road
When it was built: 1980
Why it matters: One of the region’s first – and few – earth shelter houses.
The roof of the Bob Cosby home doubles as the front yard,” began a July 26, 1981, Richmond Times-Dispatch feature by Amy Hollis. “Bob and Sheila Cosby and their three children live in an earth-covered house on Hillside Avenue… From the road, all that is visible is the ‘roof,’ a grassy slope with a picket fence on the far edges of the plot. Below the fence is a 19-foot drop to the ‘basement’ of the home.”
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A view of the Cosby earth house from the street (Photo by Julianne Tripp)
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A view of the house from the driveway (Photo by Julianne Tripp)
Robert E. Cosby Jr., half of custom-home builders Will & Cosby, was his own architect and engineer and his father was the contractor for the project. The 3,200-square-foot residence was, Cosby says, “Probably the first and one of the few of its kind around. I was ahead of my time in Virginia, [but] not ahead of people up in Canada and Arizona and down in Florida where environments are more extreme.”
The Richmond native and Virginia Tech trained engineer worked in “Condo Canyon,” those Northern Virginia high rises viewed from I-95 going toward Washington, D.C. The inspiration for his house, though, came from working on Reston’s Terraset (meaning “set in earth”) Elementary School which was built inside a knoll during the 1973-74 Arab oil crisis.
When Fairfax County sought assistance in funding a solar-energy system to assist with heating and cooling the school, the National Science Foundation denied the request. An unusual benefactor emerged: Saudi prince (later king) Fahd bin Abdul Aziz Al Saud. In 1977 solar technology wasn’t what it is now, and the panels, designed for Saudi Arabia’s climate, cracked in Virginia’s fluctuating temperatures. The school, still in use, has a meadow for a roof and skylight structures that allow natural light.
“I watched the work on that building and thought about how you could have a house built that way,” Cosby says. “Energy was getting expensive, but I built mine more for comfort and quiet.”
The house took eight months to construct. “We used the cut and fill method,” Cosby explains. After digging a deep hole, the resulting dirt went off to the side lot which Cosby owns. He built the house box out of concrete and steel. “And the end result is a berm-style house,” he says “Even though it’s an underground house, I’m looking at treetops and a little creek. Even though I’m in [a suburban neighborhood], I have a lot of privacy.”
Cosby’s home was one of a few plans around that time to introduce environmentally sensitive residential structures to the region. His house, however, is perhaps the only remaining “earth shelter house.”
The house maintains a temperature of 70 degrees in spring and fall. “There’s always a time lag,” Cosby explains. “Still in heating mode into summer and I’m still in cooling in the first of winter.” The house paid for itself about 25 years ago, he says.
For interior lighting, Cosby installed fluorescent lights, but the rooms also were equipped with incandescent bulbs for a change of mood. The home's Eastern face gets morning sun and, Cosby says, “We have as many windows as a regular house — just on one side.”
The Cosbys were at home on Aug. 23, 2011, when the 5.8 earthquake radiated from its Mineral, Virginia, epicenter. Cosby heard the noise — quite loud considering his location — and thought the origin was a large truck passing nearby. Then slight vibrations began. “And I thought, ‘Oh, it’s an earthquake,’” he says. The house sustained no damage. “Since I am underground, the structure moves with the ground,” Cosby explains. “Basically, the house is earthquake-proof.”
When asked about why there aren’t more of these kinds of houses, Cosby says his company built a number of them in the 1980s. “But everybody wanted them ‘Right now!’ And they’d buy a production house and that killed the custom builders. Everything swings one direction or another.”