Washington DC’s first energy-efficient passive home.
CREDIT: Habitat for Humanity
It’s a heavy, hot, July evening in Washington, D.C.
Ominous storm clouds, bloated with rain, hang oppressively low and there’s an eerie green glow around the corners of everything. Lakiya Culley has just gotten home from work and her three boys Kamari, Christopher and Carl — aged two to seven — are trying to play basketball in the living room without getting into trouble and now and then circling nonchalantly around the kitchen counter, eying the yet uncut chocolate cake.
The cake is a house-warming present. You wouldn’t guess it from how at home everyone seems, but Lakiya and her boys have only lived here for about a month. Like any new homeowner Lakiya is eager to show off her new digs. She loves her big second story porch, especially when the boys get rowdy.
“I can go up there and close the door for a minute and I feel like I’m in the treetops, away from it all,” laughs Lakiya, holding Kamari on her hip giving him a knowing, wry smile.
Lakiya, who has worked as an administrative aid at the Department of State for nine years, also prefers the upstairs porch because sometimes when she sits on the front porch after work she has to field a lot of questions.
“Someone the other day asked me if this was a log cabin in the city,” said Lakiya. “Someone else asked me if I was hiring, people are always taking pictures. I guess that’s because it just looks different from the other houses on the block. I don’t mind though, I like to be a little different.”
That’s because Lakiya’s new home is the first super energy-efficient passive house in D.C. It also just happens to be a Habitat for Humanity home.
The house doesn’t look like a futuristic spaceship, but it is different from the other small pre-fab houses along the street. It is a two home duplex with a big wooden porch in front and, of course, solar panels on the roof.
Lakiya’s house started out two years ago as an entry in the Department of Energy’s biannual Solar Decathlon. Dubbed “Empowerhouse” for the competition, it was an ambitious concept brought to life by engineering and architecture students from Stevens Institute of Technology, Parsons The New School for Design and Milano School for International Affairs, management and Urban Policy, many of whom had never even wielded a hammer before attempting this elaborate construction project.
The team’s dream was to build a solar-powered house that could not only compete with the most cutting-edge technologies out there, but was actually affordable and something ordinary people would want to live in.
According to Josh Layrea, one of the Stevens engineers, the winning entry from a German team two years before cost over two million dollars.
“It was an impressive piece of engineering,” Laryea concedes. “But made for exhibit, not habitation. The entire outside of the house was covered in solar panels.”
Laryea and his teammates had a different goal. In a way, they were in a competition of their own, in which they were competing against themselves to see if they could create something that Habitat for Humanity could use not only as a home for a low-income family in the Deanwood area of D.C. but also as an affordable housing prototype for Habitat going forward. The Stevens-Parson-Milano house won the top prize for cost-effectiveness at the Solar Decathlon.
Lakiya’s house was built based on passive house design principles. The basic concept of passive house is to lower energy consumption by being super-insulated and practically airtight. Empowerhouse has 12-inch thick walls and triple-glazed windows and, as a result, uses up to 90 percent less energy for heating and cooling than an ordinary house. Such low energy consumption enabled Empowerhouse to have one of the smallest solar panel arrays in the competition, which helps keep construction and maintenance costs down.
Needless to say, Lakiya’s house wasn’t two million dollars. After Habitat built a second story on the 1,000 square foot competition house, the final price tag for Lakiya’s half of the duplex was just over $200,000, on par with the typical price of Habitat construction in the area. Although passive houses are often about 15 percent more expensive to build because of the special doors and windows they require and all the extra insulation, Habitat’s financing programs and D.C. area grants mean Lakiya has a very manageable 133,000 dollar, thirty-year mortgage. And if the house proves itself to be net zero as advertised, she will save nearly $72,000 on energy costs over the course of that mortgage.
In order to become certified as a passive house, the building has to be tested for leaks and cracks that would make it less efficient. Orlando Velez, Manager of Housing Services for Habitat for Humanity of Washington D.C. explained that the test is serious business.
“They take a huge blower fan and put it in one of the doors and then close everything else up,” said Velez. “The fan sucks all the air out until the house is pressurized at fifty pascals, then they watch to see how much air is leaking [into] the house. We rush around the outside of the house with a smoker test and try to find every place we’re leaking.”
For a typical house, this test would reveal seven air changes per hour. Air changes per hour is a measurement of how many times the air in a space is replaced. To be certified as a passive house, that number needs to drop to 0.6 air changes per hour.
“That means that all the little leaks put together are smaller than a postage stamp,” said Velez. “And if you wanted to you could heat your home with a hair dryer quite easily.”
Velez remembers the excitement he felt when Lakiya’s home passed the passive house test.
“I just remember thinking, we did it, a non-profit, affordable house developer can do this, even using volunteers with no construction experience,” said Velez. “And then I started thinking, what’s everyone else waiting for?”
Parsons offered Lakiya the furniture they had used to decorate the house during the competition, but she politely declined. It was a bit space-age for her tastes, so she brought the boys’ bunk beds from her old apartment and turned the conceptual entryway into a little T.V. room for the kids after school.
Lakiya hasn’t gotten a power bill since the solar panels on her roof have been up and operational, but she’s excited to see what it looks like. She knows that the recent heat wave has kept the AC running and that her sons are a factor that wasn’t part of any neat energy consumption calculations.
“They’re kids,” she says. “They run in and out and in and out and they’re too busy chasing each other to always remember to close the porch door after them. So yes, we’re still learning how to use this house. I’ve never had an electricity bill for a house before, because I’ve never had a house before, so there’s a lot to get used to.” That bill, Lakiya hopes, will read $0 owed.
As anyone who worked on Empowerhouse hoped, Lakiya’s home is not the end of the dream. Habitat is gearing up to build six more passive houses in Ivy City, a short drive from Deanwood. They’ll look a bit different from Empowerhouse, more townhouses than duplex, but they’ll cost about the same and hopefully pass on the same savings.
“As much as we can afford, we would like to have the highest standard of energy efficiency available for our homeowners,” said Susanne Slater, President and CEO of D.C. Habitat for Humanity. “Our whole mission is to provide affordable housing to low income families, and if homeowners pay less in energy costs, that helps us reach that goal.”
“I really believe that with the mounting cost of electricity, passive houses with solar panels are going to take off,” said Slater. “And our homeowners are going to be out in front of the movement.”
