Originally, Ed Gaddy just wanted an environmentally friendly house.
He was starting a job at the Johns Hopkins University's Applied Physics Laboratory in Laurel after retiring from the NASA Goddard Space Flight Center. He wanted to find a house within walking distance that reflected his passion for environmental preservation.
"I'm an environmentalist and concerned about global warming, so having a house that was very efficient seemed very attractive to me," said Gaddy, who is 72 and spent decades designing solar arrays for spacecraft. "It's my hobby. It's something I've been wanting to do."
But that vision grew, and after seven years, Gaddy's modern industrial home in Clarksville is a national prototype for energy efficiency and eco-friendly building and design.
Surrounded by landscaping that reduces runoff and hosts native plants, the three-bedroom, two-bath rancher is Gaddy's love letter to the environment. Nestled at the back of the 1.22-acre property, the cream-colored stone house is topped by corrugated tin soffits that lend a space-age feel. A large cone-shaped solar array, designed to look more like a sculpture than the typical bank of solar panels, fronts the home.
Gaddy counts a growing list of green certifications from various granting authorities.
From the start, he wanted to build what's termed a "passive house," a certification for extremely energy-efficient homes issued by the Passive House Institute U.S. He pulled in his longtime friend Miche Booz, an architect with a similar passion for environmentally sound design, as he searched for a property.
He bought the lot, a 10-minute walk to his office at the Applied Physics Lab, in 2010. At first, he considered renovating the existing 1925 Cape Cod on the property, but it quickly became apparent that it would take more energy to renovate than to build a new house.
As Booz and Gaddy consulted various experts, their dream enlarged. They added to the list, working toward LEED certification through the U.S. Green Building Program, as well as through the Living Building Challenge, a sustainable building program.
"It became clear that Ed was pretty serious about the extent he wanted to take the house," Booz said. "He wanted it to be a prototype and a teaching tool.
"The three certifications reflects his commitment and passion for this particular subject," Booz said. "I would say it bordered on a fixation, and a good one. It's his way of contributing to what he considers a crisis on the planet. He was all in — financially, emotionally and intellectually."
But pursuing three different certifications created a new set of challenges, with overlapping criteria that didn't always match.
Planning for the project began in 2012. Construction unfolded over 17 months, from April 2013 to July 2014, rather than the typical six to nine months.
In various meetings and phone calls with five consultants and a crew of volunteers, the team searched for new materials and solutions that would fulfill the sometimes-conflicting sets of requirements. Gaddy spent hours each week researching and calling experts in the field.
Booz designed the home in three squares: a living area, which holds the kitchen, living room and dining area in an open floor plan; a private area, which holds the bathrooms and bedrooms; and the garage, which is connected to the home by a covered walkway.
The living area features a wall of south-facing windows, shielded by an outside overhang designed to capture the sunlight to warm the interior in the winter and to deflect the strongest beams during the summer.
Construction and finishing materials were chosen only if they produced zero or low Volatile Organic Compounds (VOCs), which can be harmful to people and the environment.
Floors, paint and tiling were chosen for their durability, such as the dark gray porcelain floors throughout the home and the glass tiles in the bathroom and kitchen, or for their recyclability, like the stainless steel countertops.
The refrigerator, stovetop, oven and fans in the kitchen were all the highest-rated in efficiency when they were purchased. In the bathrooms, Gaddy installed toilets that use less than a gallon per flush and waterless urinals, all in a bid to conserve water.
Point-of-use water heaters — small units installed near each spigot that start heating only when the water runs — reduce the time to heat and deliver hot water to the faucet.
Gaddy likens the home's utility closet to the engine of a hot rod, which ultimately forms the heart of its efficiency.
The home's heat recovery ventilator, which functions much like a car radiator, exchanges inside and outside air without mixing the two while still transferring the heat or cold, reducing work for the home's heat pumps. The heat pumps were the highest-rated efficiency at the time, although the home's 18-inch thick, three-layer insulated walls mean they don't run as much as usual.
Insulation covers all four surfaces of the home's exterior, including the foundation.
The material selection, sourcing of sustainable materials, use of solar power and high-efficiency windows, doors and appliances all helped Gaddy and Booz achieve their three-certification dream — almost.
The home is certified as a Net Zero Energy Building by the International Living Future Institute and will soon earn Living Building Challenge certification with six of seven criteria (called "petals") met.
It's certified LEED Platinum, the highest level, by the U.S. Green Building Council.
But that Passive House certification remains elusive, held up only by a failed airtightness test.
"It was a huge disappointment," Gaddy said.
Gaddy started testing the walls for air leaks himself. A first round of testing and patching in 2015 helped, but Gaddy eventually turned to a thermal imaging test, which identified four more areas. Once those are patched, he's hopeful he will achieve the Passive House certification.
Outside the house, the landscaping follows green principles as well.
Raised garden beds are filled with native plants. LEED and Living Building Challenge both required collecting and storing stormwater runoff — there's a large underground cistern Gaddy had installed. Along with vegetables and other fruits, the property hosts cherry, apple, walnut and peach trees, fulfilling the Living Building Challenge's requirement for urban agriculture.
But perhaps most important to Gaddy is the native fauna that have flocked to his yard. This summer, he walked across the lawn with kaleidoscopes of butterflies, many of them monarchs, and watched bumblebees fly between flowers in the landscaping.
"I had no idea how important landscaping could be," he said. "That was a whole new world to me."