September 2011: Pushing the Envelope

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“This is a statement about the future,” says builder Bill Jobes, sitting in the dining area of the house on Lankford Avenue that his company just finished. Behind him, large windows wrap around the house’s southeast corner. A close look reveals that their sills are unusually deep, due to extra-thick walls. That thickness—plus a pervasive quiet inside the house—are some of the only clues that this modern dwelling is built exceptionally tight.

Shade on the southeast-facing windows of a new house on Lankford Avenue, built with narrow gaps along the walls, help regulate the passive solar effect.

It’s been more than a year since ABODE first reported on Passive House, a new standard for energy-efficient building that comes to Charlottesville by way of Europe. Jobes expects his Lankford project, which he built on spec, to earn certification from the Passive House Institute of the U.S. this fall. That should make it Virginia’s first certified Passive House. (As we wrote last June, John Semmelhack—owner of energy consulting company Think-Little—lives in another Charlottesville house built very close to the Passive House standard, and worked with Jobes on the Lankford project.)

Unlike LEED, a much more widely-used green building standard, the Passive House concept is entirely focused on energy use; it’s the world’s most stringent standard in that respect. A building could earn LEED points for rainwater collection and minimal construction waste, but there’s only one way to be Passive: Build a super-tight house whose energy use is drastically lower—70 to 80 percent less—than a standard dwelling. The keys to this feat? Extremely high-quality triple-glazed windows, very generous insulation, and obsessive attention to airtightness.

With Lankford receiving its finishing touches and up for sale, what’s next for Passive House in Charlottesville? Jobes, for one, has applied some of what he learned at the Lankford house to a subsequent project, a “deep energy remodel” in Woolen Mills that will see a 60 to 70 percent improvement in its energy use. Meanwhile, another local building company, Latitude 38, expects to finish its first Passive House this fall. 

With just 22 houses currently certified nationwide, Passive House is still relatively unknown in the U.S. But Charlottesville, often ahead of the curve on green building, is shaping up to be a small Passive House hotbed.

And good-looking, too

For Jobes, the Lankford project represents a marriage of high design and high performance. The house, designed by Giovanna Galfione, blends modern and traditional elements and boasts quality materials: red oak flooring, slate windowsills, stucco and cedar siding. It’s blessed with abundant outdoor living space (two porches, a balcony, and a patio) to take advantage of its lofty site and long views.

The kitchen anchors an open floor plan on the first floor. Custom shelving coexists with modified ikea cabinetry.

“There are a lot of very expensive houses that look beautiful and perform terribly,” says Jobes. “We wanted a beautiful, comfortable house that worked really well.”

Local expert Mark Schuyler consulted on lighting; an open stairwell built from oak and particleboard is backlit for a special nighttime effect. Two bedrooms share a porch on the second floor, while the third floor has its own balcony and a bathroom counter made from cherry wood, harvested on-site. Custom details like geometric plywood ceilings, Italian Omnia door hardware and ipe-wood deck railings dress the house up.

But the comfort of its occupants will come, ultimately, from its performance. It’s designed to stay between 67 and 75 degrees year-round, and that’s before heat or A/C are even turned on. The triple-pane windows (brand name Serious) work with highly insulated double-stud walls to ensure that very little air, or heat or cold, can pass through the building envelope. (Fresh air is brought in with a device called an Energy Recovery Ventilator.)

Jobes and Semmelhack say it’s working. “We’re certainly feeling good about the utility bills we’ve had,” says Jobes—just $42 for electricity in July. “Everything is pointing toward pretty good performance,” Semmelhack agrees. “I’ve been over there on a couple of hundred-degree days, and the temperature from room to room, on all three floors, was within a degree-and-a-half Fahrenheit.”

Though the house does have the infrastructure to support solar panels, as a Passive House its heating and cooling loads should already be 90 percent less than is typical. “That is the profound thing about Passive House,” says Jobes. “You’re building a super efficient envelope, so you don’t need a lot of eco-bling.”

Jobes surveys the expansive view from the second-floor porch which features opaque railings for added privacy.

Number two

Nearby, in Fifeville, a steel-clad house is rising on Sixth Street: the future Passive House of Latitude 38 owners Jeff Erkelens and Joey Conover. Part of Charlottesville’s younger generation of builders—who, as a group, tend toward eco-consciousness and an integrated design-build approach —the folks at Latitude 38 have built four houses certified by EarthCraft (a different sustainability program). Ratcheting up to Passive House makes sense, they say. 

“We just like to push ourselves to do new things and build better homes,” says Conover, adding that along with energy-efficiency, indoor air quality often improves and maintenance needs lessen. Says her husband, “We love to use ourselves as a guinea pig…I think [Passive House] is going to take off.”

Their new home will have double-stud walls similar to those in Jobes’ Lankford project, along with a slightly less expensive line of Serious windows. Semmelhack helped the pair model projected energy use for various design options. “The site has a good southern orientation,” he says, “[with] fairly good shading from the trees…It was an ideal project from a Passive House standpoint.”

Custom elements combine in unusual ways: plywood ceilings, oak stair treads with stock white banisters, and lighting between the wall and staircase.

Conover and Erkelens say the project is teaching them how to build smarter. For example, Erkelens says, “[It’s] pushing us away from spray-foam insulation. We needed super insulation and it’s cost-prohibitive to use spray-foam. [Also,] John’s anti-spray-foam because the manufacturing process is really bad environmentally.” Instead, their new home will use cellulose insulation, with an extra six to eight inches installed in the attic. That’s very cost-effective, says Semmelhack: “It’s hardly any additional labor to do it.”

Forward motion

Think-Little is consulting on another Passive House in Raphine, even as Latitude 38 is planning a new project in the RiverBluff development that they hope will also meet Passive House standards. Semmelhack sees an industry growing in the right direction. “Over a five-year period it could move pretty rapidly.” 

“With builders like Jeff and Joey, [who were] already producing a really nice house in terms of energy-efficiency, it’s not a huge leap for them to get to Passive House,” Semmelhack says. Meanwhile, the energy requirements for certification programs like EarthCraft and Energy Star are set to become stricter, as are standard building codes. “The low end of the tide is rising up.”

Jobes says his experience at Lankford has made a reality out of something that seemed incredible when he first learned about it. “It’s not just a theory,” he says. “It’s totally doable.”

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