PassiveHouse
ALSO IN THIS ISSUEFast-growing Home Builders / 20
Rebounding the Woodside Way / 36
House Review: The Grand Kitchen / 52
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7 Leadership ResponsibilitiesPage 40
Converting Traf c to SalesPage 44
July 2013 www.HousingZone.com
2012 JESSE H. NEAL AWARD WINNER
The new gold standard of energy performance for U.S. builders and designers
46 Professional Builder July 2013
EED used to be the buzz-
word for energy-ef# cient
homes in the United States,
but a new standard in town
could be a game-changer:
Passive House. This con-
struction standard is the toughest one
yet, requiring very low levels of air
leakage, very high levels of insulation,
and windows with a very low U-factor.
Passive House has its roots in North
America, but it blossomed in Europe
(see timeline), where it has been an ac-
cepted standard for the last 18 years.
“Passive House has certainly taken
a big foothold in Germany and Austria
and other [European countries],” says
Mike Duclos, a Certi# ed Passive House
Consultant (CPHC) and principal of
DEAP Energy Group in Stow, Mass.
Europeans tend to view their homes as
long-term investments of 50 years or
more, rather than possessions they’ll
outgrow in three-to-# ve years. “That’s
why, in the U.S., Passive House is a
slowly growing, organic movement,”
Duclos says wryly.
The base theory of Passive House de-
sign and construction can be summed
up as follows: maximize gains and
minimize losses.
“You maximize gains via passive solar
heat gains and internal heat gains from
mechanical systems and occupants, and
minimize losses via a thick insulated
building shell and a great airtight layer
achieved through air sealing,” says Eric
Barton of Biltmore Insulated Concrete,
Highland Park, Ill., a CPHC and Passive
House Institute US (PHIUS) Certi# ed
Builder who constructs super energy-
ef# cient building shells. “This keeps the
internal heat gains within the building
envelope and living areas.”
Barton points out that because the
speci# c space heat demand and spe-
ci# c primary energy demand require-
ments are the same for all climate
zones, it’s easier to achieve Passive
House standards in a mild climate,
such as San Diego, than in a very cold
climate such as Duluth, Minn.
Most builders say achieving the
standard requires an additional up-
front investment of 5-to-10 percent.
But Falmouth, Mass., builder Christian
Valle says, “The overall incremen-
tal costs are not as signi# cant as one
might think. The tradeoffs of building
a tighter ‘mousetrap’ result in smaller
By Susan Bady, Contributing Editor
American builders and
designers are beginning
to view Passive House as
the new gold standard of
energy performance.
[DESIGN]
L
HOUSEPASSIVE
This 2,000-square-foot home in East
Falmouth, Mass., has 17-inch thick
exterior walls and R-values surpassing a
conventionally built home.
PHOTOS: JOHN L. MOORE
HVAC systems, among other things, which help offset other costs.”While Passive Houses are more chal-
lenging to build than standard homes, Valle believes that as more builders get on board, the learning curve will shorten. “The building industry has trended toward energy-ef* cient con-struction, driven by clients and more rigid energy codes,” he says. “Builders are paying attention to air-sealing and insulation details. That’s what Passive House is really about, in a nutshell.”As the movement gains momen-
tum, though, American window makers are going to have to up their game.“We don’t make great windows in
this country, but that’s starting to change,” Barton says. “Some manufac-turers are stepping up to the plate.”
Reading, Mass., architect Steven Baczek collaborated with Duclos on the Massachusetts home featured here. Baczek laments that “nobody [in the U.S.] makes a cheap, triple-glazed, Passive House-certi* ed window. Your window package is going to go from $20,000 to $45,000. On the other hand, $300 a year to heat, cool, and sup-ply hot water for a 2,000-square-foot house is pretty amazing.”
EXTREME ENERGY SAVINGSValle Group’s * rst Passive House
was built for a client who was * rmly
ARE YOU READY FOR PASSIVE HOUSE?If you’re getting involved in a
Passive House project for the
fi rst time, here are a few things
to consider:
• Become a Passive House
consultant. PHIUS offers
both virtual and in-class
training tailored to North
American climate variations,
market conditions, and
building components.
• Invest in the software. The
Passive House Planning
Package (PHPP) is available
for $225 from either PHIUS
or the U.S. Department of
Energy. The PHPP calculates
energy demand for high-
performance buildings.
Among other things, the
spreadsheet-based software
provides data needed to
determine a home’s heating
and cooling loads and
properly size its heating and
domestic hot-water systems.
• You’ll have to source
windows from Canada or
Europe.
• Precertifi cation is required
while the home is still in
the design phase. After
construction is completed, a
fi eld test will be performed
to ensure the home meets all
parameters.
• Get ready for a learning
experience, says CPHC
Mike Duclos. “Think things
through in the beginning,
and have a good plan. If you
can pull somebody into the
team who has done one of
these before, that’s a plus.”
design
RAISES THE BAR
48 Professional Builder July 2013
committed to a rigorous standard of en-
ergy ef! ciency. The home sits on six acres
of wooded land in East Falmouth, Mass.,
and includes a large organic garden.
“The biggest challenges of building
this home were the tolerances we had
to meet for air leakage, mechanical
system design, and insulation values,
and the unbelievable attention to de-
tail required during all phases of con-
struction,” says Christian Valle.
The 2,000-square-foot home has
17-inch-thick exterior walls. The
R-values surpass those of a conven-
tionally built home: R-105 in the ceil-
ing, R-72 in the walls, and R-77 in the
6 oor. The custom-built, triple-pane
windows, which were made in Canada
and shipped to the site, feature differ-
ent glazing techniques depending on
their location in the house. They allow
for maximum solar gain on the south
elevations and minimum heat loss on
the north elevations. As a result, says
Baczek, 57 percent of the home’s heat
energy is generated by the windows.
Valle Group used a combination of
insulation types including blown-in
cellulose, blown-in ! berglass, and rigid
insulation. The virtually airtight home
was subjected to several blower-door
tests during construction to detect
and eliminate any leaks. The cumula-
tive leakage of the entire home was the
size of a playing card, versus a sheet of
plywood for a comparably sized, con-
ventionally-built home.
A heat-recovery ventilator captures
heat from stale exhaust air and intro-
duces it back into the house through
incoming fresh air. The home’s heating
load is minimal, allowing a high-ef! -
ciency, electric air-source heat pump to
be used in lieu of a boiler or furnace. The
actual heating load of 8.6 million BTUs
per year is at least 50-percent lower
than the annual heating and cooling
energy consumption of a similar home
in the same climate zone, Valle says.
At press time, Valle Group was in
the design and precerti! cation pro-
cess for two more Passive Houses.
Construction is expected to begin in
the next few months.
FIRST IN CHICAGO
As a college student, Brandon Weiss
played professional basketball in
Europe. One of the towns he played
in was Darmstadt, Germany, home of
the Passivhaus Institut. “That really
opened my eyes to a better, more ef-
! cient, and more durable way of build-
ing homes,” Weiss says.
Today he runs Weiss Building &
Development in South Elgin, Ill., and
[DESIGN]
PHOTOS: TOM BASSETT-DILLEY
design
has a long list of certi! cations includ-
ing Graduate Master Builder and LEED
AP. Weiss recently built Chicago’s
! rst certi! ed Passive House—a
3,598-square-foot, three-story home in
suburban River Forest.
The clients wanted a concrete home,
which is not a requirement for Passive
House certi! cation but does add signi! -
cantly to its durability. Insulated con-
crete forms (ICFs) run from the footings
to the roof. “Part of the [reason] we did so
well on airtightness is the ICFs,” says ICF
contractor Eric Barton. “When you pour
the concrete into the ICF blocks, it natu-
rally ! lls the void, creating an airtight
exterior building shell. In a wood-frame
house, we would have had to tape all the
seams and plywood butt joints. Here,
all we had to worry about was taping
around the windows for the air sealing.”
Normally a builder would drywall the
undersides of the plywood roof trusses,
but in a Passive House the trusses are
laminated with ½-inch plywood or
OSB, and all the seams are taped. “That
helps create an airtight layer on all six
sides, which is one of the key details
and differences between Passive House
construction and conventional con-
struction,” Barton says.
Determining the correct shape and
orientation of the windows and the
amount of shading required was criti-
cal, says Oak Park, Ill., architect Tom
Bassett-Dilley, CPHC. His efforts were
aided by a solar path! nder—an engi-
neered glass dome with a grid super-
imposed underneath it. “We took pho-
tos at the center point of each façade
at the second-H oor level,” he says. “It’s
not just the south side that matters; all
four sides matter in terms of radiation,
both direct and indirect.”
In a blower-door test, the home
achieved 0.39 ACH (air changes per
A BRIEF HISTORY OF PASSIVE HOUSE
1970sThe phrase “passive
solar house” is coined to
describe houses with extra
thermal mass and extensive
south-facing windows;
demonstration houses are
built in the U.S. and Canada.
1988A conversation between
Swedish professor Bo
Adamson and German
physicist Dr. Wolfgang Feist
leads to development of
Passivhaus standard.
1991Feist builds fi rst Passivhaus
prototype in Darmstadt,
Germany.
1996Feist founds Passivhaus Institut
and obtains funding for major
research project involving
hundreds of houses all over
Europe.
2003German architect Katrin
Klingenberg builds home to
Passivhaus standard in Urbana,
Ill., and goes on to found
Passive House Institute US.
2006America’s fi rst certifi ed Passive
House is built in Minnesota.
Chicago’s fi rst certifi ed Passive House in suburban River Forest
was built with insulated concrete forms. It features triple-pane
windows and indoor-air friendly products such as zero-VOC
paints, adhesives, sealants, and formaldehyde-free cabinets.
50 Professional Builder July 2013
hour) at a pressure of 50 Pascals, well within the minimum Passive House criteria of 0.60 ACH. Bassett-Dilley says there are no cold spots: “No part of the house gets below 62 degrees, even when it’s zero degrees outside. One pellet stove can heat the entire house.” There’s no need for a furnace or air-conditioning units; instead, two small ductless, wall-mounted, mini-split heat pumps satisfy the minimal heating and cooling needs.
Weiss focused on indoor-air quality as well as energy ef9 ciency. He used drywall that absorbs VOCs in the air and no-VOC sealants, caulks, and ad-hesives. “We gave [the house] a two-week > ush-out period after construc-tion was 9 nished,” he says, to ensure there were no chemical fumes or par-ticles left in the air.
The energy-recovery ventilator pro-vides a continuous stream of fresh air to all of the living areas. “Stale or humid air is always being exhausted from the bathrooms and kitchen,” Weiss says. “The air quality in Passive Houses has been shown to be superior [to code-built homes].”
URBAN RENEWAL
Tim McDonald believes Passive House is best suited for large-scale mul-tifamily, urban buildings, and needs to be promoted as such. Long a proponent of sustainability, McDonald’s com-pany, Onion Flats, was one of the 9 rst to design and build to LEED Platinum standards in Philadelphia.
“Passive House is just a natural ex-tension,” says McDonald, a registered architect and CPHC. His group has built three certi9 ed Passive House projects to date and has three more in the pipeline. “LEED is a great holistic program to deal with sustainability, but [Passive House is a better tool for] getting down and dirty about how you actually reach net zero.”
The company’s projects include Bel9 eld, a trio of HUD-funded row-houses for low-income buyers; and The Stables, a 27-unit, market-rate townhome project. The 1,920-square-foot, three-story Bel9 eld homes are 100-percent occupied. To date, two homes at The Stables are sold and two more sales are pending. Prices start in the mid-$700,000s for the four-story townhomes, which are approximately 2,500 square feet and include optional 9 nished basements.
“We designed [both projects] to be built in a modular factory with con-ventional framing techniques, and we speci9 cally designed this building sys-tem so that it could be built with no cost premium,” McDonald says.
The Stables was developed by Onion Flats as a joint venture with Domani Developers. The building generates its own power from a 4.23 kilowatt solar PV array, and the site is 95-percent per-meable with green roofs and porous paving for stormwater management.
Finding materials has been a bit of a challenge, McDonald admits: “We couldn’t 9 nd [the windows we needed] in the United States. And we had to invent our own mechanical systems with off-the-shelf components.” PB
[DESIGN]
The insulated concrete
forms for this River
Forest, Ill., home are
18 inches thick, and the
wall frames are 24 inches
on center. A heat pump
warms and cools the
3,598-square-foot house. PHOTOS: TOM BASSETT-DILLEY
