A House Without a Furnace in Vermont
Using the Passive-House Satandard Allows a Fossil Fuel-Free Home to be
Built in Snowy Vermont
Beyond Fossil Fuels
Can We Build in a Brighter Shade of Green?
Herb Swanson for The New York Times
Barbara and Steven Landau, with their sons, Nathan and Zack, are
building an energy-efficient home to the passive-house standard, which
relies on insulation, sunlight and an airtight exterior. By TOM ZELLER
Jr.Published: September 25, 2010
Beyond Fossil Fuels
Energy Efficiency Begins at Home
Articles in this series examine innovative attempts to reduce the
world's dependence on coal, oil and other carbon-intensive fuels, and
the challenges faced.
WHEN Barbara Landau, an environmental and land-use lawyer in suburban
Boston, was shopping for insurance on the energy-efficient home she
and her husband were building in the woods just outside of town here,
she was routinely asked what sort of furnace the home would have.
"None," she replied.
Several insurers declined coverage.
"They just didn't understand what we were trying to do," Mrs. Landau
recalls. "They said the pipes would freeze."
They won't. A so-called passive home like the one the Landaus are now
building is so purposefully designed and built — from its orientation
toward the sun and superthick insulation to its algorithmic design and
virtually unbroken air envelope — that it requires minimal heating,
even in chilly New England. Contrary to some naysayers' concerns, the
Landaus' timber-frame home will be neither stuffy nor, at 2,000 square
feet, oppressively small.
It has been a good deal more expensive to build, however, than the
average home. That might partly explain why the passive-building
standard is only now getting off the ground in the United States —
despite years of data suggesting that America's drafty building
methods account for as much as 40 percent of its primary energy use,
70 percent of its electricity consumption and nearly 40 percent of its
Proponents of the standard, who note that passive homes often use up
to 90 percent less heating and cooling energy than similar homes built
to local code, say the Landaus embody the willingness of more
homeowners to embrace passive building in the United States. Even
Habitat for Humanity, the affordable-housing philanthropy, is now
experimenting with the standard.
Yet the market remains minuscule, and the materials and expertise
needed to build passive homes are often hard to find. While some
25,000 certified passive structures — from schools and commercial
buildings to homes and apartment houses — have already been built in
Europe, there are just 13 in the United States, with a few dozen more
in the pipeline.
"Even though the passive house standard is tried and true, and is used
all throughout Europe — we know it works, we know there's some
simplicity to it," says Mrs. Landau, "here in the United States, we
were reinventing the wheel."
STEVEN LANDAU, a partner at a factory design firm in Burlington,
Mass., was already an efficiency geek before the words "passive house"
entered his vernacular. He'd long ago outfitted the family's current
home near Boston with a full complement of efficient gizmos and
upgrades, including a high-efficiency German boiler and solar
collection tubes designed to pull daylight into dark corners and
Arrays of futuristic-looking LED tubes illuminate the Landaus' current
basement, and a wattage meter keeps tabs on how much juice the home is
consuming at any given time.
Mr. Landau was also well acquainted with the growing number of "green"
building certifications and rating systems in the United States,
including popular ones like the federal government's Energy Star for
Homes program and the LEED rating system, for Leadership in Energy and
Environmental Design, from the United States Green Building Council.
The goals of these various systems vary widely. Some, like LEED, award
points for a variety of environmentally friendly features, like using
sustainable construction materials, in addition to energy efficiency.
Others, like Energy Star, focus squarely on energy use.
But the most common green building standards, Mr. Landau said, fell
short of his ambitions — which included avoiding any on-site use of
fossil fuels. "I remember reading a book about someone in England in
the 1980s who built a superinsulated house that was only heated by the
body heat of the occupants and maybe a tea kettle," Mr. Landau
recalls. "I thought to myself, 'Why can't we build our houses that
Energy Star and LEED aim for efficiency improvements of at least 15
percent over conventional construction — and both programs can earn a
variety of tax credits and other incentives. The passive-home
standard, perhaps because it's unfamiliar to many officials who create
efficiency stimulus programs, is eligible for few direct government
subsidies, despite the fact that homes using it can be up to 80
percent more energy-efficient, over all, than standard new houses and
consume just 10 percent of the heating and cooling energy.
Add photovoltaic solar panels or other energy harvesting systems, and
passive homes can quickly become zero-energy-use homes — or even power
generators that can feed electricity back to the grid, according to
Katrin Klingenberg, the director of the Passive House Institute-U.S.
in Urbana, Ill.