Self-playing slideshow for Living Green Expo—highlighting the benefits and opportunities of Passive House building energy standard and Deep Energy Reduction Retrofit.
The slideshow contains a lot of full-screen images but no subtitles, therefore omitting some of the information which would have been given verbally during the presentation.
4. FAQ: Are super-insulated
buildings “green”?
Passive House building energy standard oers the lowest certified
environmental
impact and carbon footprint of any certified building standard
in the world. With its extremely reduced energy consumption, Passive House
buildings can be designed to become zero-energy, carbon-neutral, and net-
positive energy.
TE Studio takes “green” to the next level. We combine Passive House and Deep
Energy Reduction Retrofit designs with best practice management for “green”
products, materials, and construction methods creating true sustainability—
6. Info: Origins of
super-insulated buildings
Super-insulated buildings were first developed in the U.S. in the 1970s in
response to the oil-crisis. The basic concept of “conservation first” still holds
true today.
In the 1980s, cheap energy prices and lack of public energy-awareness caused
people to forget about conservation and super-insulated buildings.
Some pioneers stuck with the concept and started refining it. Super-insulated
buildings have continuously been built since the 1970s but they have not
7. Back to the future
1979 newspaper articles about the Illinois Low-Cal Houses
8. First super-insulated
building
Saskatchewan Conservation House - Saskatoon, Canada in 1977
9. “Passiv haus”
The Passive House
Building Energy Standard
A rigorous, voluntary building energy standard focusing on highest energy
eficiency and quality of life at low operating cost.
10. Certified
Passive house™
TM
The Passive House Standard is the most rigorous building energy standard in
the world. Consultants, projects or building components that have obtained
the right to carry the logo have committed themselves to design excellence
and the Passive House energy performance criteria.
TE Studio is proud to oer Certified Passive House™ consulting.
11. First Passive House,
the PHI and PHIUS
1990: 1st Passive House - Kranichstein,
Germany
Source: Passiv Haus
Institut
1996: PHI - Passiv Haus Institut
2008: PHIUS - Passive House Institute U.S.
12. Info: History of
Passive House
Researchers and architects in Europe picked up on the early work in the U.S.
and pursued perfecting it. Some light-handed legislature and public energy
consciousness helped with the inception of the Passive House concept in
1990.
Prof. Wolgang Feist is the “father” of Passive House. He also built the first
Passive House. In 1996 he founded the Passiv Haus Institut in Darmstadt,
Germany.
14. Info: History of
Passive House in the U.S.
• The first Passive House in the U.S. was built in 2003
• The first Passive House in the U.S. was certified in 2006
• In 2008, Passive House “came home” to the U.S.—the Passive House
Institute U.S. (PHIUS) was founded in Urbana, IL
• 15,000 units have been built worldwide to date, about a dozen of which in
the U.S.
• Currently there are 2 Certified Passive House™ buildings in Minnesota: The
17. FAQ: What is PHIUS?
Passive House Institute U.S., a branch of the German Passiv Haus Institut PHI,
is in charge of Passive House certification in the United States.
Learn more at www.passivehouse.us
19. FAQ: Is Passive House the
same as Passive Solar?
The short answer is no.
Many people have heard of Passive Solar. It represents a building design
concept that harnesses solar energy for heating. Passive House also makes use
of passive solar heat gains. Therefore, Passive House is a certified building
energy standard that makes use of the Passive Solar concept as one part of its
energy strategy.
21. Passive Solar Design
vs. Passive House Standard
PASSIVE HOUSE BUILDING ENERGY
PASSIVE SOLAR DESIGN
STANDARD
Building design concept Certified building energy standard
“Unlimited” energy use Limited energy use per square foot and year
Utilization of passive solar heat gains and
Utilization of passive solar heat gains
internal
heat gains of shading devices and glazing to
Utilization of shading devices to control Utilization
solar heat gains control solar heat gains
Use of thermal mass for absorption and Use of super-insulation for retention of
storage space conditioning energy
of solar energy mass for time-release of
Use of thermal
Use of ventilation system for distribution and
space conditioning energy (passive
recovery of heating energy
convection/radiation or active distribution
with mechanical system)
22. “Active” versus “Passive”
Passive House with “passive” systems
Conventional Building with
and small post-heater
“active” heating system
Uses a max. of 4,750 British thermal
Uses 5–30x more heating energy
units
than a Passive House
per square foot and year for heating
85 - 450 max.15
kWh/m2 kWh/m2
Source: Krapmeier Drössler 2001
24. FAQ: Why is it called
Passive House?
Passive House is a direct translation of the German name “Passiv Haus”.
The word “passive” refers to the setup of its heating system, which mostly
relies on passive solar and internal heat gains, paired with heat-recovery
ventilation and a small backup heater.
This concept symbolizes one of the key dierences between Passive House
and conventional buildings, which typically rely on a large “active” heating
25. Economy
Capitalized costs in Euro
Elimination of traditional heating system
Ultra low-energy building
Low-energy building
Passive House
`
Space-Conditioning Energy in kWh/(m2 a)
“Gas-Mileage for Buildings”
Source: Krapmeier Drössler 2001
27. FAQ: How much does
a Passive House cost?
Passive Houses have been built for the same cost, or even less than
comparably sized and outfitted conventional buildings. Some sources say that
a Passive House construction can cost up to 10% more than “standard
construction”.
Any increased initial construction cost for energy-saving measures are
eventually recouped through energy savings.
28. Energy
90%+ reduction in space-conditioning energy consumption*
75%+ reduction in source-energy consumption*
Source: Krapmeier Drössler 2001 *) compared to standard code-compliant construction
30. FAQ:
How much energy does a
Passive House save?
Compared to conventional buildings, Passive House reduces heating energy up
to 90% or more, and source energy up to 75% or more.
31. Opportunity:
Energy Independence
Passive House and Deep Energy Reduction Retrofit significantly reduce energy
consumption through conservation, enabling energy independence for owners
and society as a whole.
33. FAQ: What if
the power or gas go out
in the middle of winter?
No worries. Passive House and Deep Energy Reduction Retrofit oer
outstanding protection against utility outages, creating highly survivable
buildings. This is an important feature in severe heating climates that no other
design can provide.
Passive House buildings tend to retain indoor temperatures well above
freezing throughout the winter months, even when unoccupied and
unconditioned.
35. FAQ: What is the
environmental impact
of a Passive House?
36. FAQ: What is the
environmental impact
of a Passive House?
Passive House’s impressive reduction of source energy is directly linked to a
dramatic reduction of pollutants and CO2 that is produced to power it. It can
been compared to a 150MPG car in terms of its energy performance.
Passive House is the highest certified building energy standard in the world
today. This makes it the most environmentally friendly as well.
38. FAQ: What are the
health benefits of
super-insulated buildings?
39. FAQ: What are the
health benefits of
super-insulated buildings?
Super-insulated building envelopes provide high interior surface temperatures
during the heating season, eliminating radiant heat loss—the most
uncomfortable way for the human body to lose heat.
Controlled ventilation in air-tight super-insulated buildings ensures highest
indoor environmental quality.
42. FAQ: What makes
super-insulated buildings
so comfortable?
All interior surfaces stay within a few degrees of the indoor air temperature,
virtually eliminating radiant heat loss.
45. FAQ: How can I do the
right thing?
Passive House and Deep Energy Reduction Retrofit oer leading energy savings
potential and quality of life. Arguably, they are the best strategies to achieve
energy independence, protect the earth, create healthy indoor environments,
and oer truly sustainable value to owners.
The clear conscience comes standard.
48. FAQ: What about
quality and durability?
Passive House and Deep Energy Reduction Retrofit encourage quality design,
planning and execution. High performance cannot be achieved with subpar
designs, materials, and construction.
Field testing and third party verification help ensure quality and durability.
Passive heating systems use less parts and therefore require less maintenance.
51. FAQ: What value does
Passive House
certification provide?
Durability longevity through quality planning, documented construction and
certified performance.
53. FAQ: What are the key
Passive House benefits?
• Up to 90% reduced energy bills
• The lowest certified environmental impact
• Ultimate comfort and health
• Quality, durability and low maintenance
• Low total cost of ownership
55. Your dream house here!
TE Studio oers custom designs for your Passive House or Deep Energy
Reduction Retrofit project. We’ll work with you to make your dreams come
true.
57. FAQ: What does a
Passive House look like?
Passive House is a building energy standard, not a design style. A Passive
House can look similar to any “standard construction” building, with some
limitations to the building shape based on sun exposure and surface-to-
volume ratio.
The most noticeable dierences are:
• Thicker exterior walls in severe heating or cooling climates
• High-performance windows and doors
59. 1 Paradigm Shift:
.
Leapfrog versus
Incremental Approach
Passive House is a leapfrog approach to building compared to conventional
designs. It bypasses any small incremental improvements and leaps straight to
the most eficient and feasible design we can make today.
Deep Energy Reduction Retrofits bypass incremental improvements, which
while helpful in the short term, often prevent buildings from getting the
comprehensive make-over they need to become truly sustainable—both
economically and environmentally speaking.
60. 2. Paradigm Shift:
System versus Component
Approach
Each part of a building or design is reviewed in respect to its impact on the
whole building system. This results in all components working in concert to
create a whole that is greater than the sum of its parts.
63. FAQ: What is the
Building Envelope?
The slab, walls, roof, windows, and doors that enclose space inside and
protect it
from outside elements. The envelope directly eects building performance and
energy consumption.
64. Super-insulated envelope
Passive House Wall
Section
Notice
• Thicker wall and roof
assembly
• Continuous
insulation package
Compare to
standard 2x4 wall
thickness
Source: Waltjen 2007
67. FAQ: What materials
are used for
super-efficient buildings?
Many materials and products are the same as those in conventional
construction. In order to minimize heat loss/gain, the building envelope is
assembled with high R-values using great quality and care. Materials and
products have to live up to highest performance and durability standards.
While not mandatory for super-eficient buildings, TE Studio encourages the
use of
FSC-certified lumber, low or no-VOC materials, as well as reused, recycled, or
68. Passive House Corner
Assembly
Notice
• Thicker walls
• More insulation
• Deeper window jambs
• Interior window sill
• Surface-mount raceway
system (optional)
69. Advanced Windows Doors
Passive House
Window
Notice
• Insulation layer
• Triple-pane glazing
Source: Waltjen 2007
71. FAQ: Can I open the
windows in a
Passive House?
72. FAQ: Can I open the
windows in a
Passive House?
Of course, but you may not need to. The ventilation system in a Passive House
provides constant tempered, filtered outside air year-around.
In comparison, a conventional building would have to have all windows open
every
3 hours for 5-10 minutes, day and night, year-around.
77. FAQ: Why is air-tightness
important in
super-efficient buildings?
78. FAQ: Why is air-tightness
important in
super-efficient buildings?
Conventional buildings can lose up to 25% heating energy through air leakage
—typically through cracks and gaps in the building envelope.
Therefore, air-tightness is essential to any high-performance building.
82. FAQ: What about
air pollution and Mold
in super-insulated
air-tight buildings?
83. FAQ: What about
air pollution and Mold
in super-insulated
air-tight buildings?
TE Studio uses best practice management to control moisture inside buildings
and avoid pollutants from construction materials and products.
Super-insulation raises the interior surface temperature of exterior walls and
ceilings, eectively eliminating any potential for condensation and mold.
Air-tight and diusion-open assemblies allow the building to breathe.
Airborne pollutants inside an air-tight building are mitigated by dilution
85. FAQ: How do I heat
a Passive House?
Passive House utilizes 4 sources of heating energy:
1. Heat recovery ventilation system
2. Passive solar heat gains
3. Internal heat gains
4. Backup heating system
86. 1 Heat recovery ventilation
.
Duct with mufler
Air-intake with
Supply grate
Ventilation machine
Heat from exhaust air is transferred to incoming
87. 2. Passive solar heat gains
South-facing windows and doors allow sunlight in during heating months
88. 3. Internal heat gains
Copyright: Sony Pictures
People and equipment give o heat that helps warm a Passive House
91. Optional
Renewables
Source: Gumprecht Architekten
Solar-thermal domestic hot water
92. FAQ: Does a Passive House
have solar panels
on the roof?
93. FAQ: Does a Passive House
have solar panels
on the roof?
Solar panels are not required for Passive House standard. However, TE Studio
recommends using renewable energy resources whenever feasible.
Solar power can be harnessed with the help of photovoltaic panels (for
electricity) and solar-thermal panels (for hot water). Wind and water power
may also be available through local utility companies.
Renewable energy resources are essential to achieving zero-energy, carbon-
96. FAQ: Will living in a
Passive House affect
my lifestyle?
Yes, in many positive ways!
Passive House and Deep Energy Reduction Retrofit limit energy consumption,
provide healthy indoor environmental quality, and oer highest levels of
comfort.
TE Studio encourages energy-aware behavior and the careful use of extremely
eficient appliances and lighting.
98. FAQ: What is the
Gas Mileage for Buildings?
energy per square foot and year
The Gas Mileage for Buildings allows comparisons between dierent buildings
and can
be used to create absolute benchmarks to limit energy consumption, or energy
goals
for retrofits.
99. FAQ: What is the
heating-energy limit
for Passive House?
100. FAQ: What is the
heating-energy limit
for Passive House?
≤ 4,750 Btu/(sf a)
4,750 British Thermal Units per square foot and year is the maximum heating-
energy consumption allowed in a Certified Passive House™. This is about 90%
less than the heating energy consumed in a code-compliant building today.
The performance of Passive Houses is calculated with the help of an energy
modeling software called the Passive House Planning Package (PHPP).
101. FAQ: How is the
performance of Passive
Houses established?
102. FAQ: How is the
performance of Passive
Houses established?
• Energy Modeling with the
Passive House Planning
Package (PHPP)
• Performance testing
• Site supervision by a Certified
Passive House™ Consultant
• Submission of design
drawings and performance
103. FAQ: What is the
source-energy limit
for passive house?
104. FAQ: What is the
source-energy limit
for passive house?
≤ 11.1 kWh/(sf a)
Source-energy is the amount of energy that a utility company uses to provide
a building with energy on site. Depending on the energy source and the
ineficiencies of the energy extraction and delivery process, the source energy
can be as high as 3 times the site energy or more.
Limited source energy consumption helps reduce pollution and global
105. FAQ: Is a Passive House
automatically a
Zero-Energy Building?
106. FAQ: Is a Passive House
automatically a
Zero-Energy Building?
No, it still needs a minimal amount of energy to provide a comfortable, healthy
indoor climate. Passive House balances economy and ecology.
TE Studio recommends using renewable energy to cover the small remaining
amount of energy needed and encourages construction of net-positive
energy buildings.
107. Closest to Zero
“STANDARD
CONSTRUCTION”
LEED ENERGY STAR
PH TM
Net-Positive Energy
Building
109. FAQ: What does
zero-energy mean?
Zero-energy describes a building performance where the amount of energy
produced on site from renewable sources equals the amount of energy
consumed on site.
A zero-energy building can be grid-tied or o-the-grid. O-the-grid tends to
be expensive due to the fact that energy needs to be stored on site. It is most
feasible in areas where a grid is not available.
112. FAQ: What does
net-positive energy mean?
Net-positive energy describes a building performance where the energy
produced on site from renewable sources is more than the amount of energy
consumed on site.
Typically, this performance level is achieved by combination of conservation
and on-site energy generation from renewable sources.
Passive House is an ideal starting point towards a net-positive energy goal, as
113. Think globally,
Build locally.
Passive House building energy standard performance requirements are always
the same, no matter where built.
Climate zone and a building’s distinctive location impact the design
significantly.
Therefore, Passive Houses will look dierent depending on where they are
located.
115. FAQ: Can I retrofit my
building to become
super efficient?
116. FAQ: Can I retrofit my
building to become
super efficient?
Most buildings can be upgraded with a Deep Energy Reduction Retrofit.
Feasibility of a Passive House-type retrofit is directly linked to the existing
building and can be evaluated on a case-by-case basis.
TE Studio can help develop the best strategy for your existing building.
118. FAQ: What is a
Deep Energy Reduction
Retrofit?
Deep Energy Reduction Retrofit as described by Aordable Comfort, Inc. is a
comprehensive sustainable building improvement that oers significantly
reduced environmental impact and energy vulnerability while enhancing
comfort, indoor environmental quality, and durability.
It oers the potential to turn buildings from liabilities into assets.
120. FAQ: What is
Affordable Comfort, Inc.?
Aordable Comfort, Inc. (ACI) is an organization dedicated to moving existing
homes towards carbon neutrality. ACI coined the term “Deep Energy Reduction
Retrofit”.
More information at: www.aordablecomfort.org
121. FAQ: Why reduce 70% of
the energy in a building?
Why not 30%?
122. FAQ: Why reduce 70% of
the energy in a building?
Why not 30%?
Experts agree that 70%+ energy reduction in existing buildings is needed to
halt
and reverse the impact of global warming.
The return on investment is more favorable at higher energy reduction, with
greater savings on energy bills and elimination or significant down-sizing of
mechanical equipment.
While the cost to add more insulation is incremental, the work to install more
Conservation became a resource!
Wayne Schick’s Team at The Small Homes Council @ the University of Illinois, Urbana-Champaign develops the Lo-Cal House in 1974-76
Walls: Double stud R-30, Roof: R-40
Were built, still in operation
We’ll get back to Urbana, Illinois later in the presentation
We are now seeing articles like this again in newspapers! People are starting to notice that conservation is a resource to reckon with.
The term \"superinsulation\" was coined by Wayne Schick at the University of Illinois at Urbana-Champaign. In 1976 he was part of a team that developed a design called the \"Lo-Cal\" house, using computer simulations based on the climate of Madison, Wisconsin.
In 1978 the \"Saskatchewan House\" was built in Regina, Saskatchewan by a group of several Canadian government agencies. It was the first house to publicly demonstrate the value of superinsulation and generated a lot of attention. It originally included some experimental evacuated-tube solar panels, but they were not needed and were later removed.
In 1979 the \"Leger House\" was built by Eugene Leger, in East Pepperell, Massachusetts. It had a more conventional appearance than the \"Saskatchewan House\", and also received extensive publicity.
Publicity from the \"Saskatchewan House\" and the \"Leger House\" influenced other builders, and many superinsulated houses were built over the next few years, but interest declined as energy prices fell. Many US builders now use more insulation than will fit in a traditional 2x4 stud wall (either using 2x6 studs or by adding rigid foam to the outside of the wall), but few would qualify as \"superinsulated\".
There is no set definition of superinsulation, but superinsulated buildings typically include:
▪Very thick insulation (typically R40 walls and R60 roof)
▪Detailed insulation where walls meet roofs, foundations, and other walls
▪Airtight construction, especially around doors and windows
▪a heat recovery ventilator to provide fresh air
▪No large windows facing any particular direction (unlike passive solar, which uses large windows facing the sun and fewer/smaller windows facing other directions).
▪No large amounts of thermal mass
▪No active or passive solar heat (but may have solar water heating and/or hot water heat recycling)
▪No conventional heating system, just a small backup heater
Nisson & Dutt (1985) suggest that a house might be described as \"superinsulated\" if the cost of space heating is lower than the cost of water heating.
First superinsulated house that showed that airtight construction is feasible. It is equipped with a ventilation system with an air-to-air heat exchanger.
Peak heat load at -10 degrees Fahrenheit is 3000 watts (10,640 Btu per hour)
Walls: 12” thick, R-44 Roof: R-60
There is no set definition of superinsulation, but superinsulated buildings typically include:
▪Very thick insulation (typically R40 walls and R60 roof)
▪Detailed insulation where walls meet roofs, foundations, and other walls
▪Airtight construction, especially around doors and windows
▪a heat recovery ventilator to provide fresh air
▪No large windows facing any particular direction (unlike passive solar, which uses large windows facing the sun and fewer/smaller windows facing other directions).
▪No large amounts of thermal mass
▪No active or passive solar heat (but may have solar water heating and/or hot water heat recycling)
▪No conventional heating system, just a small backup heater
Nisson & Dutt (1985) suggest that a house might be described as \"superinsulated\" if the cost of space heating is lower than the cost of water heating.
Due to the dramatic reduction in space-conditioning energy needs, it is referred to as a passive house,
as opposed to utilizing active measures to keep it conditioned.
The difference being mainly in the energy amount that utilized and the fact, that passive house utilizes mostly solar and internal heat gains (passive energy sources).
Economy: Significant conservation and improved performance = cost savings to the owner
90%+ savings on space-conditioning energy, 75%+ savings on source energy (pending household use pattern)> highly reduced utility cost
Federal tax credits, local utility company incentives (as applicable)
Potentially reduced homeowner’s insurance (due to reduced mechanical system and quality construction)
Benefits of energy efficiency mortgage
Cost asymptote occurs when a traditional heating system is eliminated
Energy: Significant conservation and highly efficient operation
Significantly less energy consumption
Can be “fueled” by virtually any power source (future proof), Easier to “fuel” with renewable energy sources, cheaper to outfit with appropriately sized renewable energy sources, Crisis proof
Renewables are smaller, hence more affordable. Zero site, or source energy, carbon neutrality, deep energy retrofit
Environment: Significant conservation and improved performance = significantly reduced environmental impact
Up to 75% savings on source energy = smaller CO
2
footprint: Carbon-neutrality truly in reach. Don’t need a football field of PV panels
Likely in use longer and maintained longer than average building, Less likely to need retrofit, reduction in energy used for construction and materials
Health: Improved indoor environmental quality = improved health
Guaranteed mechanical air-exchange 24/7—365 days a year, Tempered air (heat recovery ventilation), Controlled humidity, Slow and steady air movement (quiet and without drafts)
Indoor surfaces are near room temperatur, virtually no radiant heat-loss potential
Improved daylighting and solar exposure
Studies show less potential for asthma, allergies, sickness
Significantly reduced exposure to CO, pollutants, VOCs. Virtually no potential for mold, no radiant heat loss, healthy humidity levels, little to no noise pollution
Comfort: Superinsulated building envelope = high level of comfort
Indoor surfaces are near room-temperatur, virtually no radiant heat-loss potential
Improved indoor environmental quality
Extremely quiet inside due to superinsulation and high-performance windows
very high (virtually no radiant heat loss, healthy humidity, fresh air, etc.)
Conscience: Most efficient building energy standard available today = clear conscience
Durability: High quality planning and construction = extremely durable building
Energy modeling, quality-controlled construction, field testing > predictable results
Advanced window technology, longevity
Reduced mechanical system, less moving parts = less maintenance
Owner training, “understand your building”, Owner’s manual, “pass on the knowledge”
Certified building standard
Value: Best building energy standard available = incredible value
Quality building, durability
High performance building envelope
Fully documented and certified
Best starting point for an uncertain energy future
sells up to 25% quicker, yields up to 10% more
R-21 to R120+ (pending location)
thermally broken windows, all connections designed thermal-bridge free
2 to 4-pane windows*, high solar heat gain
solid or thermally broken frames*
field tested with a sequence of three test, pressurized and depressurized
impecable, continuous solid air-tight layer (i.e. OSB), thorough detailing, precise execution
max. 0.6 ACH. Air-admittance valve.
Heart of the mechanical system, provides most of the energy (up to 10W/m2), 90%+ efficient, balanced and duct-blasted, short duct runs, insulated ducts
Other mechanical systems: insulated pipes, central location, air admittance valves, energy and water saving appliances, potentially renewable sources
Proper orientation, solar exposure, proper summer and swing season shading, high solar heat gain glazing on south side.
Near southern orientation, built-in shading
people, appliances, equipment
people, appliances, equipment
people, appliances, equipment
How do we measure the success?
In Germany, we look at gas-mileage for homes. Instead of MPGs, we measure in kWh/m2 a or Btu/sf year
How do we measure the success?
In Germany, we look at gas-mileage for homes. Instead of MPGs, we measure in kWh/m2 a or Btu/sf year
≤ 15 kWh/(m2 a)
U.S. housing stock ~175 kWh/(m2 a) or 58,580 BTU/(sf yr) up to 90% + improvement
determined in PHPP
Achieved with the help of: Superinsulated Building Envelope, very good windows and doors, air-tight and thermal bridge-free construction, passive solar heat gains, internal heat gains, and an very efficient backup heating system
≤ 15 kWh/(m2 a)
U.S. housing stock ~175 kWh/(m2 a) or 58,580 BTU/(sf yr) up to 90% + improvement
determined in PHPP
Achieved with the help of: Superinsulated Building Envelope, very good windows and doors, air-tight and thermal bridge-free construction, passive solar heat gains, internal heat gains, and an very efficient backup heating system
How do we guarantee the result?
- Contractor training
- Extremely detailed design drawings
How do we guarantee the result?
- Contractor training
- Extremely detailed design drawings
≤ 120 kWh/(m2 a)
up to 75% + improvement
determined in PHPP
Achieved through conservation in both passive and active systems
≤ 120 kWh/(m2 a)
up to 75% + improvement
determined in PHPP
Achieved through conservation in both passive and active systems
How do we measure the success?
In Germany, we look at gas-mileage for homes. Instead of MPGs, we measure in kWh/m2 a or Btu/sf year
In U.S. we currently use a comparative model: HERS
Problem: nobody really knows what the basis is and buildings are compared on a point basis. Nowhere does it directly relate back to energy.
Limited use, but realtor associations are looking to use it for a “green” realty label, MN starting 2009. HERS is determined by HERS rater.
HERS (Home Energy Rating System), controversial and not absolute- uses comparison not actual energy modeling or monitoring
Ratings provides a relative energy use index called the HERS Index – a HERS Index of 100 represents the energy use of the “American Standard Building” and an Index of 0 (zero) indicates that the Proposed Building uses no net purchased energy (a Zero Energy Building). Zero Site energy, nor really a zero energy building though.
What is a HERS Rating?
A home energy rating involves an analysis of a home’s construction plans and onsite inspections. Based on the home’s plans, the Home Energy Rater uses an energy efficiency software package to perform an energy analysis of the home’s design. This analysis yields a projected, pre-construction HERS Index. Upon completion of the plan review, the rater will work with the builder to identify the energy efficiency improvements needed to ensure the house will meet ENERGY STAR performance guidelines. The rater then conducts onsite inspections, typically including a blower door test (to test the leakiness of the house) and a duct test (to test the leakiness of the ducts). Results of these tests, along with inputs derived from the plan review, are used to generate the HERS Index score for the home.
The HERS Index
The HERS Index is a scoring system established by the Residential Energy Services Network (RESNET) in which a home built to the specifications of the HERS Reference Home (based on the 2006 International Energy Conservation Code) scores a HERS Index of 100, while a net zero energy home scores a HERS Index of 0. The lower a home’s HERS Index, the more energy efficient it is in comparison to the HERS Reference Home.
Each 1-point decrease in the HERS Index corresponds to a 1% reduction in energy consumption compared to the HERS Reference Home. Thus a home with a HERS Index of 85 is 15% more energy efficient than the HERS Reference Home and a home with a HERS Index of 80 is 20% more energy efficient.
For more information, visit the RESNET Web site .
Comparing the New HERS Index with the Old HERS Score
For homes rated before July 1, 2006, the rating score is known as a “HERS Score.” The HERS Score is a system in which a home built to the specifications of the HERS Reference Home (based on the 1993 Model Energy Code) has a HERS Score of 80. Unlike the HERS Index, each 1-point increase in a HERS Score is equivalent to a 5% increase in energy efficiency. Please see the table below for a comparison of the HERS Score and the HERS Index.
OUTLOOK AND POTENTIAL
Bringing it back to the issue of climate change, energy independence, affordability (utility bill).
There is not a better starting point than Passive House - it requires the least amount of energy, it is the easiest building type to get to any of the aforementioned states.
Goals should be set upfront with homeowner.
Don’t need them, optional.
Solar hot water is great way to go.
Climate and site play a role. PV can help offset energy: site, source, cost, CO2 neutral
OUTLOOK AND POTENTIAL
Bringing it back to the issue of climate change, energy independence, affordability (utility bill).
There is not a better starting point than Passive House - it requires the least amount of energy, it is the easiest building type to get to any of the aforementioned states.
Goals should be set upfront with homeowner.
Let’s talk more about details of Passive House Design.
A house build to current energy code in Minnesota could potentially qualify as a Passive House in California.
First Passive House in urban setting. First in Twin Cities. Affordable Housing. 3112 6th St. N, Eco Village, Hawthorne, North Minneapolis
PH design lends itself well to affordable housing:
- low and predictable operating cost
- high survivability (doesn’t cool off)
- empowerment through design (don’t just give people anything, give them something really good)
Thank MinneAppleseed for their support of Passive House design. Enjoying that process much of bringing hope to a community that is lacking attention, resources, opportunity.