After that, the team quickly constructed Goodhope and Quast's custom, stick-built, A-frame cabin - in just 100 days. "The house went up fast," Goodhope recalls. The crew lived on-site in a trailer during much of the building process. This eliminated the two-hour drive from the site to the Spearfish and back.

Off-Grid and Golden 

The A-frame's walls, floor, and roof have sprayed and blown-in insulation. The triple-pane windows allow in most of the passive-solar heating; a wood stove provides the rest. An air system buried about seven feet underground, which uses 3,000 linear feet of four-inch drain tile, also helps to cool the home in summer and provide supplemental heat in the cold months. A fan pushes air through the tubes to continually circulates air that's 56 to 57 degrees. "We use that system mainly in the summer, if we need it," Goodhope says. 

Along with the solar panels, a lithium battery weighing about 350 pounds (and about the size of a mini-fridge) powers the home's LED lights, a UV filter in the well, and other electrical needs. "That battery can power the house for up to three days," Goodhope says.

"We wouldn't change a thing about the structure," says Quast. "It's more solidly built than we anticipated. It holds the coolness and heat well. That it's so well insulated, so quiet, and we don't have to manage the temperature at all, is a wonderful surprise." 

Goodhue's father also noticed that the house reflects the golden ratio - also known as the golden section, golden mean, or divine proportion - that appears in nature and architecture. Designers in ancient Greece used the golden ratio to plan a building's width and height in ways that would create the most pleasing proportions. 

A Real Gift

Last year, the Discovery channel featured Cap and the South Dakota A-frame. The Black Hills Pioneer previewed the show and asked Cap why he enjoys building off-grid homes. Cap talked about how he loved taking "a bare piece of land which, by a lot of people's standards, is unbuildable," and creating a beautiful, off-grid home there replete with modern conveniences from a dishwasher to clothes washer and dryer.

"Cappie is a builder and an artist, that wonderful blend of expertise and creativity," Quast says. "The notion that you can walk outside and get dirty and play in the forest, then come back to all of the modern conveniences you need to clean up, cook a nice meal, and sleep comfortably—we're amazed by that. It was a real gift for him to build us something like this."