Wrzeski cites the importance of effective
ventilation systems. In the last decade, he notes, theres been a
trend towards creating a thoroughly insulated, tightly-constructed
"thermal envelope" that limits air infiltration and allows a
house to stay warm in the winter and cool in the summer. But as
Wrzeski points out, "people, plants, and pets create
moisture." Without proper ventilation, a tightly-built house can
trap this moisture, which may lead to condensation on windows,
internal rot, or high levels of humidity. Also, improper air
circulation for instance, from ventilation fans that create high
levels of suction can cause drafts, including downdrafts in the
chimney. If you move air correctly, Wrzeski stresses, "you
minimize the amount of energy you have to use."
To get rid of this moisture and ensure proper air
flow, savvy builders install high-quality bathroom fans and range
hoods that are suited to a households needs, and they also make
sure that a houses thermal envelope is not blocking off the intake
or exhaust path of furnaces and water heaters. These devices need what
is called "combustion air" to keep their fires going, and as
Wrzeski points out, "every cubic foot of air that comes in has to
go back out."
To get rid of this moisture and ensure proper air
flow, savvy builders install heavy-duty fans in the bathroom and
powerful range hoods in the kitchen, and they also make sure that a
houses thermal envelope is not blocking off the intake or exhaust
path of furnaces and water heaters. These devices need what is called
"combustion air" to keep their fires going, and as Wrzeski
points out, "every cubic foot of air that comes in has to go back
Nowadays, many houses have what is called
"sealed combustion" for their water heaters and furnaces.
One pipe brings in air; another takes it out again. Some water heaters
now use powered ventilation. In addition, there are recovery systems
available that can take excess heat from another part of the house
from an air-conditioning unit, for instance and put it back in the
Windows are another important aspect of a houses
total system, because they are typically the weakest link in a houses
thermal envelope. A houses "r" value refers to the
resistance of heat flow, and windows have the lowest "r"
value in the envelope. One current trend among builders is the
installation of what are called "low-emissivity" or
"low-e" windows. These windows are double-glazed; i.e., have
two panes of glass with an insulating layer of air or gas in
between,with special coatings that reflect radiant heat. In the
winter, these coatings throw heat back inside the house, and in the
summer, they reflect it outward.
A house, Wrzeski says, should be looked at as
several different zones of activity. People can focus improvements in
energy efficiency on rooms that they use the most. He adds that some
new houses have systems that can shut off different zones.
One important trend in home construction is the
establishment of practices and standards for builders to follow so as
to make houses more
energy-efficient. The Wisconsin Environmental Initiative offers a
program called Green Built Home. This voluntary program is available
to builders throughout the state, reviews and certifies new houses
based on an extensive checklist, which contains over 200 suggestions
on such matters as insulation, sealing, water heating and windows, to
name just a few. To receive certification, builders earn points by
fulfilling certain basic requirements and then implementing additional
suggestions. Consultants from the program make site visits to verify
Dirk Mason, the director of the Green Built Home
program, says good insulation is essential for energy conservation,
but notes that the insulation has to be installed correctly to be
effective. "How its put in really matters," he says. He
cites two new insulation trends: permanent concrete forms that
insulate a basement, and insulated structural panels that can serve as
A basic requirement for builders participating in
Green Built Home is
certification from another Wisconsin program, Energy Star Homes.
Administered by the Energy Conservation Corporation, a non-profit
organization that manages all statewide residential energy-efficiency
programs, Energy Star Homes certifies a new house as being
energy-efficient after several site inspections and performance tests.
Right now, there are 160 builders actively constructing houses in the
Energy Star program.
Ed Carroll, program manager for the Wisconsin Energy
Conservation Corporation, explains that site inspections help
contractors identify ways to improve energy efficiency. For instance,
Carroll notes that, when framing a house, contractors often
inadvertently create escape routes for air, which site inspectors
tried to catch. "Energy Star homes are 23 percent less leaky than
the average," he notes. Another overlooked area is a houses
orientation to the sun, so it can take advantage of passive solar
Other forms of solar power such as solar heating
photovoltaic, or "P.V." panels, which convert the suns
radiant energy into electrical current havent yet caught on in
the mainstream. "The cost is too high," Carroll notes.
However, the efficiency and aesthetics of solar technology is
improving, and this clean, renewable energy source will
definitely be something to look out for in the future.
Like Wrzeski, Carroll stresses the importance of
proper ventilation. "Ventilation doesnt have to be
expensive," he says. "It just has to work well."
Whether youre having a house built or just remodeling, you will
ultimately save money by upgrading your bathroom fan and range hoods.
Carroll notes that bathroom fans are now available with timers and
dehumidistats, which further cut costs. He also suggests upgrading the
blower motor in forced-air furnaces and central air-conditioning
units. A high quality, variable-speed motor will consume a third the
power of an average blower.
One possible future trend is something called
"distributed generation." This is essentially local power
production, with some kind of small power generatora micro-turbine,
for instanceset up to service a particular neighborhood or city
block, perhaps during off-peak periods. But dont expect this
scenario to be arriving at your doorstep any time soon. For now, were
all in this together.