Net Zero Energy Homes CASE STUDY 1 Idaho St. Jude Dream Home

Net Zero Energy Homes CASE STUDY 1
Idaho St. Jude Dream Home
PROJECT PROFILE
City/State Boise, Idaho
Climate Zone ASHRAE CZ 5B
HDD/CD 5861/2807
Completion Date May 2010
Number of Stories 2
Number of Bedrooms 3
Lot Size N/A
Gross Square Footage
Conditioned Area 1940 SF
Builder/Contractor Flynner Homes
Energy Consultants John Coldiron
and Associates, David Hales from
Building America/WSU
Architect Paul Hoffman
Cost to Build $340,000, $175/SF
Occupants 1
Ductless Air-Air
Heat Pump
Raised Heel
R-70 Roof
65% Efficient
HRV Ventilation
Tri Pane 0.2
U-Value Windows
All CFL Lights
2 ACH-50
8.2 kW PV Array
Dbl Wall R-58
Slab on Grade R-40
Solar Thermal
underslab/R-15 perimeter
Hot Water
Sustainability Certifications
NAHB Gold | Northwest Energy Star Certified | HERS Score of -12
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OVERVIEW
GENERAL DESCRIPTION
In 2009, Scott Flynn of Flynner Homes was approached by the St. Jude Children’s Research Hospital to design, build,
and construct a home for the St. Jude’s Dream Home Giveaway Program. The program’s intent is to raise money
for St. Judes through the donation of labor, building materials, and money to build a home that will later be raffled
off for charity. The 2009 fundraising program also incorporated the idea of designing the home to have net zero
energy usage. Flynner Homes served as the builder for the entire operation and finished the project in May 2010 with
donated or reduced-cost building materials, HVAC systems, and labor. The home was raffled off for charity and one
occupant currently lives in the roughly 2,000 square foot, two-storey, three-bedroom house with a detached garage.
The project location resides within a neighborhood of sustainable 100% ENERGYSTAR homes in Boise, Idaho, is
located right off the city’s distinct greenbelt along the river.
SOUTH ELEVATION
NORTH ELEVATION
MAIN LEVEL FLOORPLAN
2
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PROCESS
DESIGN METHODS
At the onset of the project, the builder, the architect, and energy consultants all took an active role in the design of the
home, which continued throughout the process. The architect took a more direct role in designing the floor plan and
spatial arrangement of the house before working extensively with the builder and energy consultants to create the
design of the envelope assemblies, mechanical systems, and other energy efficient features of the home. Integrated
meetings were held throughout a 4-6 week period of time, where all parties were present to work through coordination
and design issues in an attempt to reach the highest performing home possible.
Additionally, this project is unique in the fact that it had a very unconventional client: St. Judes Hospital. Although
it was originally their idea to conceive a net zero energy home for the project, they took little to no involvement
throughout any of the design process.
ENERGY MODELING
John Coldiron and Associates
handled the energy modeling of the
project and, originally, considered
using two different
software
packages for the project: Energy
Gauge and REM Rate. Close to the
beginning of the process, REM Rate
was favored due to Energy Gauge’s
difficulty in modeling custom, high
performance envelope assemblies.
The specification of its components
was
limited
to
pre-defined
assemblies that did not reflect
high
performance
construction.
Consequently, REM Rate was the
primary software used to model a
HERS score for the different energy
codes and certification standards
the project was pursuing. While
REM Rate does have the capacity to
calculate building performance such
HERS INDEX
-12
post-pv
40
pre-pv
ENERGY MODEL STATS
as heating/cooling loads, energy
consumption, and energy cost
analysis, it was mainly used to model
compliance for different certification
programs. A third software, Rightsoft,
was utilized to support the sizing
process of the HVAC system and
loads of the project. From a design
standpoint, the energy modeling
process was used mainly to help
design the photovoltaic system and
ensure its capacity to meet the net
zero goals of the project.
As a modeling software, REM
Rate was able to handle most of
the specification needs for the
high performance project.
The
software proved to be powerful
enough to define custom envelope
assemblies with any insulation value.
Additionally,
these
parameters
also took into account simplified
reduction factors for thermal bridging
by specifying the percentage of
wood within the assemblies. For
infiltration, the actual ACH value
was entered from a blower door test
conducted on site. There were some
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Peak Heating
(Btu/hr)
Peak Cooling
(tons)
Heating Energy
(kBtu/SF/yr)
Cooling Energy
(kBtu/SF/yr)
Hot Water Energy
(kBtu/SF/yr)
Lighting/App Energy
(kBtu/SF/yr)
Subtotal Energy
(kBtu/SF/yr)
PV Production
(kBtu/SF/yr)
=
Net Energy
(kBtu/SF/yr)
9.6
0.8
-3.5
-0.9
-0.1
-13
-18
+45
+27
Modeled
Annual Bill
+$178
Actual Annual
Bill
$N/A
3
MODELED ENERGY END USES
issues, however, with the definition of the HVAC system in the energy model.
The software contained different types of pre-packaged systems, including
the project’s air-to-air mini-split heat pump system. however, the pre-defined
performance capacities (SEER, COP, etc.) did not equal the performance of
the actual installed equipment. Consequently, a different type of heat pump
system (vertical loop ground source setup) with the appropriate COP was
used as a workaround. The HVAC definition also lacked the ability to model
different thermostat set-point schedules, therefore the constant set point of 68
degrees Fahrenheit for heating and 78 degrees Fahrenheit for cooling were
utilized throughout the entire year.
PROCESS
At the time of the energy modeling process, the consumption values for the
different premium electrical appliance plug loads were not available from the
manufacturers. As a result, the highest energy efficient default values were
defined for the annual consumption using the energy star compliant plug load option within the program. The software
does have the capability to specify exact consumption rates of the equipment, so a post-occupancy inventory of all
the different appliances could be gathered and input into the model now that more information is available on the
specified appliances. Given this information, the “Lights and Appliances” portion is the most prominent consumer of
annual electrical energy in the home. This trend is typical in most high performance houses, when the space heating
and cooling loads become so small that the plug load portion of the energy consumption picture becomes a large
percentage of overall usage.
From a design standpoint, the energy modeling process was used mainly to ensure compliance and to also help
design the photovoltaic system and ensure its capacity to meet the net zero goals of the project. However, the
software does contain a backend post-processing feature that disaggregates the heating and cooling costs into their
components, an analysis that can be used effectively to guide the design of the energy efficiency measures of the
project. Multiple types of reports can also be generated from the data and can range from air leakage rates, to utility
rates, and even emissions statistics.
PROJECT CERTIFICATIONS
The project team chose to pursue the National Association of Home Builders (NAHB) green building standard as its
sustainability certification goal. The standard defines green building for single and multifamily homes, residential
remodeling projects, and site development projects, while still allowing for the regional flexibility of green building
practices. In 2007, NAHB and the International Code Council created the ICC 700 National Green Building
Standard, which is the first green building rating system to undergo the full consensus process from the American
National Standards Institute (ANSI).Currently there are four thresholds including Bronze, Silver, Gold, and Emerald.
Certification level is based upon energy/water/resource efficiency, lot and site development, indoor environmental
quality, and homeowner education. Unique to this standard, the level of certification is based upon the lowest level
of performance throughout all the categories. The Idaho St. Jude’s Home project achieved a Gold level certification
under this standard. The project team chose this rating system over the LEED rating system based upon NAHB’s
smoother application process, less expensive certification, and less rigorous documentation requirements.
IDAHO ST. JUDES
GOLD
4
LEVELS
The project also earned the Energy Star certification standard, whose program targets multiple energy efficiency
measures including insulation, windows, infiltration, distribution losses, HVAC systems, and appliance/lighting
improvements. The process of certification involves the builder choosing an energy rater and following a prescriptive
or custom modeling approach to develop energy efficient home features. Next, construction begins and a rater
performs multiple inspections and diagnostics. Once the rater completes the final inspection and determines all of
the requirements have been met, the project becomes certified.
BRONZE
222
SILVER
406
GOLD
558
EMERALD
558
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ENVELOPE
FLOOR ASSEMBLY
SLAB ON GRADE
A slab on grade floor system was
chosen for the project based upon its
efficiency of construction. The detail
utilizes an eight inch stem wall system
with five inches of rigid insulation that
runs continuously down to the footing
with a resistance value of R-15. A
fiber cement board served as the
outer layer of the assembly to protect
the rigid foam above and below
grade. The slab itself is four inches
thick with seven inches of continuous
underslab rigid insulation over
four inches of sand, which houses
perforated drainage pipes for radon
R-15 PERIMETER
R-40 UNDERSLAB
control. Despite what the slab detail
shows, a modification to the design
was made thermally breaking the
slab from the stem wall with one inch
of rigid insulation placed between
two components; the slab was also
poured to taper toward the thermal
break to maximize the amount of
insulation at the intersection and
reduce thermal bridging.
highly coordinated before the slab
was poured. The system prohibits
any access to the underside of the
house, which makes it difficult to fix any
wiring, plumbing problems, etc. The
alternative assembly that the project
team considered included an insulated
crawl space with an insulated rat slab.
This system would solve the access
issues while maintaining a high level
of insulation, but it would also increase
The slab on grade system might have cost through added materials and
provided smoother constructability, labor.
but logistical issues between the
electrical and plumbing had to be
Slab Air Sealing and Vapor Retarders
A ten millimeter polyethylene vapor
retarder was located in between
the slab and the rigid insulation
where it was protected. More
information about the air barrier
and its relationship to the slab will
be covered in a later section of the
report. The slab on grade system
also proved to be useful in terms of
dealing with air sealing penetrations
through the slab. Typically, most of
the plumbing pipes and electrical
conduit sections were wrapped in
plastic before the concrete pour,
which created a completely sealed
penetration around the utilities.
Additionally, only the bathtub
and p-trap called for blocked out
penetrations, which were later filled
with spray foam to air seal cracks in
the blocked out spaces around the
utilities.
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WALL ASSEMBLY
DOUBLE WALL
STUD/IJOIST
R-58
14” THICK
ENVELOPE
The project team decided to execute
a double-stud wall system, utilizing a
typical four inch stud wall assembly
and a nine inch truss joist (TJ),
partially cantilevered on the exterior
but still able to bear loads from the
roof. The entire wall composition
is as follows. starting from the
inside of the house and working
toward the outside: drywall, four
inch stud wall with spray foam and
blown in batt insulation (BIB), OSB
sheathing, nine inch TJ filled with
dense pack BIB, Zip Wall OSB, fiber
cement board siding. The entire
14” thick wall assembly adds up to
an R-58 wall system. Both walls
carry structural loads which is an
approach that deviates from the
normal double wall system, which
hangs the exterior wall truss from the
interior load bearing stud wall. In this
case, since both 2’-0” on center walls
are structural, their spacing can be
staggered to break thermal bridging
through the framing of the wall
assembly. However, the complexity
of the double wall system became
an issue on the second storey of the
house, where parts of the lower roof
came to meet sections of the second
storey wall. The increased thickness
of the profile of the wall assembly
required the relationship between
the stud wall and TJ to reverse so
that the stud wall was the exterior
wall system and the TJs were moved more conventional double-stud wall system might be better suited due to its
to the interior. The project team simplicity, ease of construction, and potential for a complete thermal break in
expressed that, for future projects, a between the two walls.
Insulation, Air Barriers, and Vapor solely a BIB system, which had to
Retarders
be blown in from the exterior of the
building through the sides of the walls
The four inch stud wall was flash before framing the exterior of the truss
insulated with three inches of with the ZIP Wall OSB. The project
spray foam, and then filled in with team felt that the spray foam’s high
dense-pack blown in blanket (BIB) expense was more than offset by its
insulation. Flash insulating is a multivalent ability to highly insulate the
technique that refers to partially building (R-6/inch for a medium density
filling a cavity with a particular spray polyurethane spray foam), serve as a
media. The nine inch TJ utilized vapor retarder, and its effectiveness at
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air sealing penetrations through the
interior wall cavity.
The project has essentially three
air barriers. The spray foam inside
the four inch stud wall which acts
as both an air barrier and a vapor
retarder, a TYVEK wrap in between
the interior OSB and the TJs, and
finally the exterior ZIP WALL OSB
layer all serve as an effective air
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OSB ZIP WALL SYSTEM
EXTERIOR
FRAMING
STAGGERED
DOUBLE WALL
ENVELOPE
barrier.
The ZIP Wall system
is a specialized OSB structural
sheathing with taped seams that
create a rigid and continuous air
barrier assembly. The panels and
tape seal the assembly’s seams
and penetrations, cutting off airflow
pathways that compromise air
tightness and energy performance.
The system also provides moisture
protection
during
and
after
construction. In addition to the air
sealing and air barrier approaches,
the team strategically located the
mechanical and electrical utilities
inside the interior wall, which is
always within at least two of the
air barriers. Only the dryer vent
penetration traverses the entire wall
assembly and all three air barriers,
effectively reducing the number
of through wall penetrations and
potential air pathways.
Blower Door Tests
The project team utilized two blower
door tests throughout different
stages of the construction process
to calibrate and adjust air sealing
strategies to reach an air tight
envelope. The first blower door test
was conducted after the installation
of the roof lid and the first level
of spray foam was applied to the
interior framing. The team used a
thermal imaging camera to identify
problem areas during the test,
which were targeted and fixed on
the spot with additional spray foam
and caulking. The final blower door
test happened after the project was
finished and the team expressed
dissatisfaction with the final ACH50
of two air changes per hour. They
felt that the most likely culprit for
the insufficient air tightness came
from the flared out wall base detail,
which potentially created a problem
at the intersection of the sill plate and
stem wall.
ROOF ASSEMBLY
RAISED HEEL
20” TYP
LOOSE FILL
R-70
The roof system consists of a continuous soffit-ventilated attic with raised heal trusses. The actual heights of the
raised heels vary according to the roof section, but are typically around twenty inches tall. A non-vented attic was
considered for the project, but was dismissed due to its increased cost. The project team also felt that it was a
consensus amongst the building community that when the attic is super insulated, then the energy performance
between a vented and unvented attic were similar. In terms of insulation, the top of the interior ceiling roof deck was
coated with one inch of spray foam to form the air barrier, before piling on loose fill insulation to achieve the desired
R-70 value.
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ENVELOPE
WINDOW ASSEMBLY
TRI PANE VINYLE CASEMENT U-.2 SHGC
The project uses multiple types of Atrium brand triple pane vinyl windows, each with slightly varying performance
characteristics. These differences arise primarily due to the types of operation, casements versus fixed for example,
which perform differently with respect to insulation (U-value), solar heat gain (SHGC), and visible light transmittance
(VLT). The U-values range from .18 - .22, the SHGC from .21 -.42, while the VLT varies from .34 - .42. The windows
are installed within the exterior half of the thickened assembly with the window flange mounted at the outermost
sheathing. The design of the house capitalized on the increased daylighting opportunity that the thickened wall
opening provided. The interior of the wall opening is chamfered, which effectively provides a more pleasing transition
of surface brightness between window and wall planes and leads to a better quality of interior daylight.
In terms of operability, the windows are either fixed or outward–swinging casement windows, chosen based upon
their air tightness and un-subdivided structure, which reduces thermal breaks in the assembly. The main living
space on the ground level of the home was designed to incorporate a passive direct gain heating strategy, utilizing
an exposed dark-stained concrete floor, .42 SHGC windows, and a 26% glazing to wall area ratio. A horizontal openlouver shading device is attached onto the south façade of the house to create a 60 degree shading cutoff angle,
which effectively shades the window during the summer and admits sun during the winter.
SHADING DEVICE
8
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SYSTEMS
HVAC SYSTEM
The heating and cooling loads of the
Daikin Minsiplit Heat Pump @ 17 F 22,000 Btu/hr
project are handled by a ductless
Ductless 4 Port Air-to-Air Source
@ 47 F 32,000 Btu/hr
mini-split air-to-air heat pump. The
four-port Daikin unit has a heating
@ 95 F 30,600 Btu/hr
HSPF 9.2 COP 3.4 EER 10.3 SEER 17.6
season performance factor (HSPF)
of 9.2, a coefficient of performance
(COP) of 3.4, an energy efficiency
ratio (EER) of 10.3, and a seasonal
energy efficiency ratio (SEER)
of 17.6. The system has a rated
heating capacity of 32,000 Btus/
hr at 47 degrees Fahrenheit and a
30,600 Btus/hr cooling capacity at
95 degrees Fahrenheit. At the lower
end of the performance curve, the
system can produce 22,000 Btus/hr
at a 17 degrees Fahrenheit outdoor condition which drops its coefficient of performance down to 2.3. The Rightsoft
program that was used for sizing the system calculated a 20,382 btus/hr heating peak at nine degrees Fahrenheit,
the listed ASHRAE 99% heating design condition. Additionally, the system has nearly 3 times the cooling capacity
of the modeled peak cooling load of 10,381 Btus/hr calculated at 94 degrees Fahrenheit, the listed ASHRAE 1%
cooling design condition. This amount of oversizing on the cooling side is unavoidable due to the fact that heat pumps
are restricted by their heating performance. The unit specified for the project was the smallest size available to the
design team at the time, which reflects the disparity between the market and the loads of net zero energy homes.
Regardless, the oversized premium unit’s high efficiency made it the best choice for pursuing the project’s all electric
and net zero energy goals. A ductless distribution system was preferred due to its lack of distribution losses and the
increase space efficiency of small diameter pipes versus ducts. Each fan coil unit also has an oscillating fan, which
reduces air stratification from the wall cassette’s high placement in the space.
The four-port unit contains one compressor and four individual fan coil units, or heads, which are located in the three
bedrooms and the dining room. Each line has variable refrigerant flow capability, which gives the individual rooms
a high degree of thermal control for the occupants. Additionally, the two smaller bedrooms have smaller head units,
with a 6.9 Btus/hr/sf capacity, while the master bedroom and dining room have the two larger 9.65 Btus/hr/sf capacity.
All four units have a combined 33 Btu/hr/sf capacity, when the house’s modeled load was 9.6 Btu/hr/sf. Since each
zone has its own thermostat and individual control, the bedrooms can respond effectively to the large temperature
caused by their location on the perimeter of the house. This system is more responsive and efficient than utilizing a
centralized thermostat, which is the case with most residential construction.
VENTILATION
65%
115W
100CFM
SENSIBLE
A heat recovery ventilator (HRV)
EFFICIENCY
provides both ventilation and a
portion of the space heating/cooling
requirements of the project. The project
POWER
team felt it necessary to utilize an HRV
DRAW
because the blower door tests showed
a level of air tightness that warranted
AIR
mechanical ventilation for indoor air
FLOW
quality reasons. Additionally it made
sense to recover heat from such a high
performance envelope to help reduce the load for the main HVAC system. While the unit lacks an economizer mode that
bypasses the heat exchanger core when outdoor temperatures are within the comfort range, it also lacks any controls that
would turn off fan power when windows where open and the home was being naturally ventilated. The efficiency of the Bryant
HRV BBSHA 1100 is 65% and has a 100 CFM capacity. The project team noted that the efficiency is significantly lower than
what should typically be used on high performance homes, but they were limited to what was donated to the project. The
100 CFM capacity was sufficient to reach a natural ACH goal of three when combined with the infiltration rate of the house.
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The actual unit is located in the attic, but is placed in a built out and spray foamed cavity to incorporate the main
part of the equipment into the conditioned space of the house. However, the six inch flex ducts still run through the
unconditioned attic space, so they are wrapped with an R-8 insulation and sealed with mastic to prevent distribution
losses throughout the system. There is a single supply in the downstairs main living area with returns in the upstairs
bathroom and the laundry room downstairs. Human occupancy movements and door undercuts are the method used
to move the air throughout the rest of the house.
DOMESTIC HOT WATER
SYSTEMS
The hot water system was originally designed to house an 80 gallon tank in a volume underneath the main staircase,
but the shorter, wider tank did not fit in the space. Consequently, a taller and slimmer 119 gallon tank had to be used
along with a two panel solar evacuated tube system. This amount of capacity was needed to heat the larger tank,
but was oversized when compared to the amount of hot water needed for the house. An external heat dump system
had to be used to counteract the oversized system and prevent unwanted heat gains from the tank in the summer.
The project team explained that their ideal scenario would have been to have some type of exterior ventilation for the
room that contained the hot water tank to counteract heat gains in the summer and still provide internal heat gains in
the winter.
RENEWABLE ENERGY
10
4.2
W/sf
8.2
kWh
array
The total capacity of the two
photovoltaic arrays amount to 8.2
kW/hr with two 96% efficient 5000
watt inverters. There are a total of
44 Lumos LS panels that have a 185
watt capacity. The southern roof
pitch of the main roof is angled at 42
degrees, which should be optimal
for the photovoltaic array’s electricity
production at Boise’s latitude. A
secondary array is located on the
garage, which is titled slightly less
and receives some shading from
the main two storey volume of the
house. Consequently, the panels
on the garage are connected to one
of the 5000 watt inverters on two
different legs to avoid compromising
the entire array when it is shaded.
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CONCLUSION
COST INFORMATION
The cost to build the house, if the items would not have been donated, would have equaled around $340,000 at about $175 per
square foot, which does not include tax credits or incentives. The cost information of this project warrants special consideration
due to its philanthropic nature of donated materials and labor. However, some of the significant costs came from the heat
pump system, which would have totaled $8,500 at an installed cost. The 8.2 kW photovoltaic array priced in at $60,000 for its
cost before installation, with a potential $20,000 tax credit if the project would have been pursued conventionally. In terms of
high performance homes, the project team stressed the need to spend money on energy efficiency measures first to lessen
the need for photovoltaics and their large first cost, which is the most significant budgetary consideration for a NZEH.
PERFORMANCE
occup.
ENHANCED
month
bill
May
-$29
Jun
-$46
NONE
July
-$60
SINGLE OCCPANCY
Aug Sep Oct Nov Dec
-$51 -$5 -$9 $87 $93
J an
$74
May through June shows a time when the house was being shown off for the St. Jude’s Dream Home Giveaway raffle.
This involved multiple showings of the house, constant traffic throughout the day, and an enhanced occupancy with more
than normal energy consumption. During the next two months, the house was completely shut down before the client
moved in during September 2010. While the house should expect a positive energy usage in the late winter months, the
project team felt that the amount of consumption was still higher than what should be expected for the home. The project
team conducted a commissioning visit that revealed a 73 degrees Fahrenheit thermostat setpoint for heating as well as
above normal hot water temperature setpoints. The whole process reflected the need to educate the client about net zero
energy operation of the home and provide some type of dashboard energy monitoring system.
LESSONS LEARNED
The project team learned multiple lessons about a variety of different aspects associated with the execution of a
Net Zero Energy home.
→→ Team management and clear goal setting was pivotal for conceptual clarity and organization.
→→ Using the same team throughout multiple projects helped defray learning curves and create a sense of trust and integrated
design on the project.
→→ The biggest education issue between the trades revolved around the framing and insulation subcontractors. The complicated
stud and truss joist double wall system, coupled with the need for advanced framing techniques, warranted special training
for the framers. Additionally, the dense pack insulation strategy required increased coordination between these two trades.
→→ The project team learned a great deal about double wall systems in general and would choose a simpler system in the future.
→→ Slab on grade floor systems required increased coordination.
→→ Space requirements for solar hot water tanks should have been highly integrated into the house to avoid oversizing issues,
providing ample space for the tank, and helping to mitigating thermal swings from the equipment.
→→ Educating the occupant has been a key factor to the realization of a net zero project.
→→ Aside from photovoltaic incentives, a recent heat pump rebate, and energy star appliance rebates, both state and federal
policy still lacks performance-based incentives for residential projects.
→→ Getting the local city inspectors to sign off on the different elements of the house was a huge impediment to the project.
→→ Educating the community, subcontractor, clients, etc. is the best way to influence the market.
THE FUTURE OF NET ZERO
Lastly, the project team felt that many people are not as serious about building to this rigorous energy standard.
The project team also posited that the rapid adoption of terms like “green” and “sustainable” happened too quickly
for the market to be able to comprehend the term’s true effect in the residential market. This concept was arguably
responsible for previous clients asking the team for photovoltaic panels before ever understanding the need for
energy efficiency as a starting point for higher performance. The project team also felt that the residential retrofit
market would surface as the next large trend in residential energy efficiency. The future high performance and
NZEH would target reducing the energy use of the existing residential building stock primarily because of its large
potential energy impact and cost savings.
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SPECIAL THANKS TO
• Scott Flynn and John Coldiron for providing the information used to
create this case study
• Flynner Homes for providing the photographs of the project
• Flynner Homes and Paul Hoffman for providing all of the drawings and
details for the project
• The owner for providing the utility data on the project
Case study researched and created by:
Integrated Design Lab Boise
306 Sth 30th Street
Boise, ID 83702
[email protected]
idlboise.com
Authors:
Jacob Dunn
Gunnar Gladics
Kevin Van Den Wymelenberg
CONCL.
Graphics:
Jacob Dunn
Alen Mahic
Funding Provided by:
The Northwest Energy Efficiency Alliance
421 SW Sixth Ave, Suite 600
Portland Oregon 97204
503-688-5400
[email protected]
http://neea.org
Point of Contact:
Anne Brink
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Sponsored by the Northwest Energy Efficiency Alliance | Created by the Integrated Design Lab | 2011