Introduction to Passive House building standard.
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.
1. Passive House
An introduction by Tim Eian
Tuesday, November 18, 2008 1
Thanks for inviting me to talk about Passive House Design Standard.
Thank people for coming
Excited to be here and talk about Passive House
Quick background on my person:
- German, lived here 7 years, family and house, worked with local firm for 6.5 years, have always been fascinated with architecture and how things work. Architectural degree more technical
in Germany (engineerʼs title), have had a fascination with efficient approaches to design.
This talk: General Introduction to Passive House: Why it is important (relevance), History, some Metrics, Opportunities
some of it is for experts, try to keep it brief
2. Why?
Tuesday, November 18, 2008 2
Why are we looking at voluntary building standards if there is a building code?
Doesnʼt code cover all the important aspects of construction and operation?
Code is not necessarily science-based (sometimes lobby-based, sim. politics).
Energy does not traditionally play a key role in how we build buildings.
Energy consumption in the US is largest per capita in the world. (approx. 2x Europe, 4.6x global average - World Resources Institute 2003, www.wri.org)
Therefore, US responsibility for protecting the planet bigger than other nations, and there is a bigger potential for significant savings.
US is leader in the world and many nations aspire to its standard of living. We have a chance for positive leadership position
3. U.S. Energy
Consumption
Buildings
Transportation
Industry
25%
48%
27%
Source: architecture2030.com
Tuesday, November 18, 2008 3
Where does all the energy go in this country?
We talk a lot about transportation, yet buildings consume much more energy.
4. U.S. Electricity
Consumption
Buildings (Operation)
Industry
Transportation
1%
23%
76%
Source: architecture2030.com
Tuesday, November 18, 2008 4
When looking at electricity, this is even more obvious.
5. U.S. Energy
Mix 2007
Fossil
Renewable
Nuclear
8%
7%
85%
Source: www.eia.doe.gov
Tuesday, November 18, 2008 5
US Energy mix mostly fossil fuel based. That contributes to the big GHG issue.
(overall energy use 2007 for US, Energy Information Agency)
6. CO 2- Green House Gas
U.S. Fossil Carbon Emissions
Top CO2 Emitting
Countries (2005)
1. USA
2. Peoples Republic of China
3. Russian Federation
4. India
5. Japan
Source: http://cdiac.ornl.gov/
Tuesday, November 18, 2008 6
2005 numbers show USA at top, China now in the lead.
Countries BRICK following U.S. lead into a largely carbon based economy
(Brazil, Russia, India, China and south Korea) (possibly Mexico, and South Africa)
Show graph for US trend. Point out energy crisis in 1973
280 ppm CO2 is pre-industrial level, now at 384 ppm causing 2C or 3F temp increase
Why is CO2 bad?
CO2 has a residence time (sim. radioactivity), takes time to dissipate and reduce
Even if we stop making it today, it will take time to decrease. CO2 currently is largest contributor among GHGs besides water vapor
7. Global Warming
Tuesday, November 18, 2008 7
Environmental impact: Melting ice caps, rising sea-levels, diminishing fresh water supplies, more severe weather events
Health impact: disease, pests, heat-stress related death, displacement (environmental refugees)
Donʼt want to get into the issue of global warming and how much of it is man-made vs. cyclical. That is irrelevant for the conversation. Since it is going up and creating problems, we need to
take action and reduce contributions significantly right now.
Cannot go from oil-based economy, to the next GHG-increasing economy (hydrogene takes more resources right now, nuclear: waste issue not solve, national security issues).
There arenʼt any negative consequences in polluting the earth less. Worst case, we conserve and save money. It is a win-win situation.
8. Energy Independence
Tuesday, November 18, 2008 8
Energy is a national security issue and a financial Issue:
US is energy importer, energy doesn't always come from the most stable places in the world,
money spent in other countries is money lost to local economy!
Rising energy costs: $350 per household in MN and rising - almost second mortgage. Huge retrofit potential.
Energy independence will increase national security and help keep more money here at home, help the economy.
How do we achieve energy independence?
We need energy policy to create a strategy - or we can take matters into our own hands and make a difference where we can today
9. Energy Outlook
Source: International Energy Agency
Tuesday, November 18, 2008 9
Problem though!
Right now the predictions are going in the opposite direction.
What can we do today to bring it down, without sacrificing lifestyle, comfort, economy?
10. Solution
The change requires rigorous adjustment of the
infrastructure and an intelligent lifestyle.
Supply Demand
Replace fossil fuels Significantly improve efficiency
Tuesday, November 18, 2008 10
We can either make dramatic changes on the supply side, or to the demand side.
Fact is, one measure alone probably wonʼt get us there since changes are mostly incremental (small steps at a time - like gas mileage on cars inching up even though we know how to make
a really efficient car.
11. Architecture 2030 Challenge
To accomplish this, Architecture 2030 has issued The 2030 Challenge asking the
global architecture and building community to adopt the following targets:
• All new buildings, developments and major renovations shall be designed to meet
a fossil fuel, GHG-emitting, energy consumption performance standard of 50% of
the regional (or country) average for that building type.
• At a minimum, an equal amount of existing building area shall be renovated
annually to meet a fossil fuel, GHG-emitting, energy consumption performance
standard of 50% of the regional (or country) average for that building type.
• The fossil fuel reduction standard for all new buildings shall be increased to:
• 60% in 2010
• 70% in 2015
• 80% in 2020
• 90% in 2025
• Carbon-neutral in 2030 (using no fossil fuel GHG emitting energy to operate).
These targets may be accomplished by
implementing innovative sustainable design
strategies, generating on-site renewable power and/
or purchasing (20% maximum) renewable energy and/
or certified renewable energy credits.
Source: architecture2030.com
Tuesday, November 18, 2008 11
Here is an example of an incremental approach - explain briefly.
This one is actually very ambitious. It also doesnʼt tell us exactly how to get there (read bold type)
Therefore, we need a comprehensive approach, an integrated approach to look at solutions in a new way to change their efficiency from the ground up.
We need to leapfrog! (and yes, I still subscribe to this model because it is the best one out there)
12. What did we do
the last time this happened?
Tuesday, November 18, 2008 12
We had a similar event in recent history, the oil crisis in 1973. Main focus was energy, not so much the environment but it just so happens that they go hand in hand.
13. Conservation
Tuesday, November 18, 2008 13
1973, energy crisis spurred first wave of energy conserving designs
Those dealing with buildings started to look at superinsulation, passive solar design concepts, and active solar systems.
Smart, integrated design.
Why solar? If we harness 0.02% of the sunʼs energy that hits the earth, we can eliminate all fossil and nuclear fuels.
14. Conservation as Resource
Illinois Lo-Cal House, 1974
Tuesday, November 18, 2008 14
Conservation became a resource!
Wayne Schickʼs 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
Weʼll get back to Urbana, Illinois later in the presentation
15. Back to the Future
Tuesday, November 18, 2008 15
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 quot;superinsulationquot; 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 quot;Lo-Calquot; house,
using computer simulations based on the climate of Madison, Wisconsin. The house was never built, but some of its design features influenced later builders.
In 1978 the quot;Saskatchewan Housequot; 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 quot;Leger Housequot; was built by Eugene Leger, in East Pepperell, Massachusetts. It had a more conventional appearance than the quot;Saskatchewan Housequot;, and also received
extensive publicity.
Publicity from the quot;Saskatchewan Housequot; and the quot;Leger Housequot; 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 quot;superinsulatedquot;.
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 quot;superinsulatedquot; if the cost of space heating is lower than the cost of water heating.
16. First Superinsulated
Building Envelope
Saskatchewan Conservation House
Saskatoon, Canada in 1977
Tuesday, November 18, 2008 16
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 quot;superinsulatedquot; if the cost of space heating is lower than the cost of water heating.
17. What happened?
Tuesday, November 18, 2008 17
Why donʼt we have those buildings everywhere today?
Problem: materials and products were not up to the task, yet (small issue)
Mid-1980s, energy became cheaper again (big issue)
No political mandate for energy-conservation measures (big issue)
Some energy codes had been released. Most consumers felt that energy-code would take care of the issue—failed to notice that it did not.
So we stopped making energy efficient houses almost entirely.
18. The Focus Shifted
Tuesday, November 18, 2008 18
We added vinyl siding to a passive solar house from the mid-70s, and we forgot how it worked. Everybody who knew how to operate it, left. The people who own it now donʼt know anything
about it.
Some buildings have been retrofit by taking the passive solar off and and adding traditional heating systems.
Slowly the issue went away. Only few people continued to work on efficiency.
The rest of the country focused on growth. Average new house grew from 1,660sf (1974) to 2,521SF (2007) +51%
median is even at 2277 in 2007
Bigger house, not better house!
19. In the Meanwhile
On the other side of the Atlantic
Tuesday, November 18, 2008 19
The good news is, not everyone stopped working on an integrated design concept.
The early ideas were expanded upon and improved:
20. Passive House Standard
Tuesday, November 18, 2008 20
The Passive House Design Standard was developed!
(This is the certificate that you receive when your Passive House is certified)
21. Passive House Founders
Prof. Bo Adamson Dr. Wolfgang Feist
Sweden Germany
Tuesday, November 18, 2008 21
The Passive House standard originated from a conversation in May 1988 between Professors Bo Adamson of Lund University, Sweden, and Wolfgang Feist of the Institut für Wohnen und
Umwelt Institute for Housing and the Environment in Germany
Inspired by early work in the US
Started with research projects
Created Passive House Standard
Inspiration: early work in the U.S.!Their concept was developed through a number of research projects [8], aided by financial assistance from the German state of Hessen. The eventual
building of four row houses (terraced houses) was designed for four private clients by architects professor Bott, Ridder and Westermeyer.
After the concept had been validated at Darmstadt, with space heating 90% less than required for a standard new building of the time, the 'Economical Passive Houses Working Group' was
created in 1996. This developed the planning package and initiated the production of the novel components that had been used, notably the windows and the high-efficiency ventilation
systems. Meanwhile further passive houses were built in Stuttgart (1993), Naumburg, Hesse, Wiesbaden, and Cologne (1997) [9].
The products developed for the Passivhaus were further commercialised during and following the European Union sponsored CEPHEUS project, which proved the concept in 5 European
countries over the winter of 2000-2001.
While some techniques and technologies were specifically developed for the standard, others (such as superinsulation) were already in existence, and the concept of passive solar building
design dates back to antiquity. There was also experience from other low-energy building standards, notably the German Niedrigenergiehaus (low-energy house) standard, as well as from
buildings constructed to the demanding energy codes of Sweden and Denmark.
22. Passive House Standard
“Passivhaus”
A rigorous, voluntary building energy standard
focusing on a high performance envelope with a
resulting minimized mechanical system and small
space-conditioning (heating/cooling) energy load.
Certified by the Passive House Institute (PHI)
or the Passive House Institute U.S. (PHIUS)
Tuesday, November 18, 2008 22
Definition: The term passive house (Passivhaus in German) refers to the rigorous, voluntary standard for energy use in buildings. It results in ultra-low energy buildings that require little
energy for space heating or cooling.
A similar standard, MINERGIE-P, is used in Switzerland.
The standard is not exclusive to residential construction. Passive House design is NOT an add-on or supplement to architectural design, but an integrated design process with the
architectural design.[3] Although it is mostly applied to new buildings, it has also been used for retrofits.
23. First Passive House & PHI
1990
1996: PHI - Passiv Haus Institut
Source: Passiv Haus Institut
Tuesday, November 18, 2008 23
What does it look like?
The first Passivhaus buildings were built in Darmstadt, Germany, in 1990, and occupied the following year.
Who is in charge of Passive House standard?
In September 1996 the Passivhaus-Institut was founded in Darmstadt to promote and control the standard.
In November 2007, launch of the Passive House Institute US
24. Passive House Standard
vs. Passive Solar Design
Passive Solar Design Passive House
Building design concept Comprehensive, certified building standard
No standards for energy Limits energy use per square foot and year
Utilizes solar heat gains Utilizes solar heat gains and internal heat gains
Utilizes shading devices to control solar heat Utilizes shading devices and glazing to control
gains solar heat gains
Uses thermal mass to absorb and store solar Uses superinsulation to retain space conditioning
energy energy
Uses thermal mass to release heating energy—
Uses ventilation system to distribute and recover
sometimes through passive convection,
heating energy. Thermal mass plays a role for
sometimes with active mechanical system
cooling loads, is not essential to concept
augmentation
Tuesday, November 18, 2008 24
Have we not seen this before?
Better known in the U.S.: Passive Solar Design. (Talk about differences in table)
Summary: Passive House Design utilizes Passive Solar Design principles but takes it to a higher level, by adding more strategies to retain energy, utilize internal heat gains, and energy
recovery to create an energy balance. It is a certified building standard—not just concept.
Passive solar design
Following passive solar building design techniques, where possible buildings are compact in shape to reduce their surface area, with windows oriented towards the equator (south in the
northern hemisphere and north in the southern hemisphere) to maximize passive solar gain. However, the use of solar gain is secondary to minimizing the overall energy requirements.
Passive houses can be constructed from dense or lightweight materials, but some internal thermal mass is normally incorporated to reduce summer peak temperatures, maintain stable
winter temperatures, and prevent possible over-heating in spring or autumn before normal solar shading becomes effective.
25. How does it work?
• A building is already warm inside going from summer
into fall and winter
- Passive House minimizes heat loss through insulation,
windows & doors, and heat-recovery ventilation
therefore retaining space-conditioning energy very
effectively
+ Passive House utilizes passive solar heat gains through
windows
+ Passive House utilizes internal heat gains from people
and appliances
+ Additional heat comes from a tiny backup system for
peak heat-load
Tuesday, November 18, 2008 25
How exactly does it work?
Talk about heating-dominated climate, explain heat retention is most important (keeps heat out, too)
26. Energy Balance
Source: Krapmeier & Dressler 2001
Tuesday, November 18, 2008 26
summarize losses and gains
Every house works that way but passive house has an improved strategy:
27. Basic Design Principle
First: Minimize losses
Then: Maximize gains
Tuesday, November 18, 2008 27
Traditionally, add as much energy as it takes to heat or cool
BTW, that is a very common approach in most industries today - if we need to change a state of an object or environmental parameters, we usually do that by utilizing more energy to do so.
Example: Air Conditioning: On hottest day with most solar energy, we use a lot of electricity (from mostly coal) to cool houses (instead of shading properly, and harnessing the sunʼs energy)
28. Schematic
Source: Krapmeier & Dressler 2001
Tuesday, November 18, 2008 28
PH is an integrated system - all components work in concert. It is not a “bolt-on solution” but it can also incorporate bolt-on measures.
29. Active vs. Passive
Source: Krapmeier & Dressler 2001
Tuesday, November 18, 2008 29
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).
30. Passive House Promise
90% reduction in space conditioning energy
75% reduction in overall energy consumption
Estimated U.S. Building Stock
Tuesday, November 18, 2008 30
US stock slightly better due to the fact that wood has lower thermal conductivity than masonry. But higher household electricity and DHW numbers.
In a Passive House: Domestic Hot Water becomes biggest energy load (typically its heating and/or cooling)
31. Measurable Performance
LEED
Tuesday, November 18, 2008 31
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 homeʼs construction plans and onsite inspections. Based on the homeʼs plans, the Home Energy Rater uses an energy efficiency software
package to perform an energy analysis of the homeʼs 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 homeʼs 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.
32. Financial Viability
1. Optimize the building envelope
2. Minimize the mechanical system
Cost asymptote occurs when a
traditional heating system is eliminated
Tuesday, November 18, 2008 32
Does this ever pay for itself?
Explain graph. Still based on German data - will backfill with US data as it becomes available. Markets are not entirely different, chances are that viability will be similar. Will definitely work
better in cold-climates due to increases savings (different climate zone, same standard!) - works in Germany with modest climate, can definitely work here.
33. Cost Efficiency
Tuesday, November 18, 2008 33
Cost efficient Passive Houses as EUropean Standard. The nine buildings presented here are not only exemplary, but can be built within the financial
requirements of low-cost housing. CEPHEUS, a European-wide consortium of experts dedicated to passive house standards, offers concrete examples
that will be of keen interest to architects and engineers wherever cost-effective, non-intrusive heating is required.
Germany looking to make PH code in 2020.
Energy Pass required for new construction (sim. to Energy Star). MN energy pass next year for home sales.
34. Standard vs. Passive House
Comparison New Construction Home U.S. average Passive House (since 1995)
Insulating values R-21 to R-38 R-21 to R-120*
Window glazing 2-pane windows, low solar heat gain 2 to 4-pane windows*, high solar heat gain
Window frames solid frame solid or thermally broken frames*
Air Tightness @ 50 Pa 3 - 5 ACH max. 0.6 ACH (≥ 0.1 CFM per square foot)
Space conditioning energy 36,600 Btu/sf yr. (2007) max. 4,750 Btu/sf yr. (up to 90% less)
Primary or source energy (16.6 kWh/sf yr. site energy 2001) max. 11.1 kWh/sf yr. (up to 75% less)
Sun & Shading Random orientation, shading not a concern Near southern orientation, built-in shading
Initial Cost $300,000 (2007) $324,000 (estimated)
Ventilation natural/random, sometimes mechanical guaranteed air change with mechanical
low to high (radiant heat-loss, dry air, stale air very high (virtually no radiant heat loss,
Comfort
etc.) healthy humidity, fresh air, etc.)
Significantly reduced exposure to CO,
Potential effects on human Mold, radiant heat-loss, humidity (leck of), pollutants, VOCs. Virtually no potential for
health noise, CO exposure, pollutants,VOCs mold, no radiant heat loss, healthy humidity
levels, little to no noise pollution
sells up to 25% quicker, yields up to 10%
Resale baseline
more
Renewables are smaller, hence more
Incremental “greening”. Limited potential for
Opportunity affordable. Zero site, or source energy,
energy and CO2 reduction
carbon neutrality, deep energy retrofit
*) Depending on climate zone
Tuesday, November 18, 2008 34
Go over table and explain: talk about utilities for space conditioning energy and primary energy
Summary of benefits
Economy: Utilities, value, resale
Energy: Significant conservation, small CO2 footprint
Health: Improved indoor environmental quality
Comfort: Temperature, humidity, noise
Maintenance: Reduced (passive approach, less stuff)
Value: Best product, arguably - “green sells”
PH does everything better and is hence referred to as a leapfrog approach.
35. Leapfrog vs. Incrementalism
Tuesday, November 18, 2008 35
So it appears that in PH design we have a leapfrog approach like we talked about earlier
In order to achieve the necessary goals to really help reduce global warming green house gases we need bypass the standard approach of incrementalism and leapfrog.
Integrated concept vs. bolt-on fix (cannot work, always missing something).
Again, how do we do it?
Conservation first (cheaper, more effective, regardless of energy source—always pays for itself), then use renewables to help with remaining small amount of energy.
Renewables more affordable and realistic for house that consumes little, than house that consumes more.
36. Think globally,
Build locally.
Passive House Standard performance requirements are
always the same, no matter where the building is built.
Climate zone and a building’s distinctive location
impact the design significantly.
Therefore, Passive Houses will look differently
depending on where they are located.
Tuesday, November 18, 2008 36
Letʼs 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.
37. Different Climate,
Same Energy Requirement
Minnesota
Twin Cities: approx. 8,000 HDD
Duluth: approx. 10,000 HDD
Source: energy.gov
Tuesday, November 18, 2008 37
Most of central Europe is one climate zone, thus making Passive Houses across Europe fairly similar, in terms of envelope, mechanical systems, etc.
US is much more interesting. 5 climate zones will spur more distinctive designs to meet the requirements in each zone.
Basic 3 Zones: Modest (sim. Europe), Cooling dominated, Heating dominated (MN)
Result: Weʼll have to take a bit of extra care in MN, which is true for any building in general, otherwise buildings donʼt perform well or last as long as they should
38. Passive House
Construction
Similarities and Differences with Standard Construction
Tuesday, November 18, 2008 38
Going to show some details of what makes a Passive House - and a really good building in general. Same principals apply to standard construction (should apply) donʼt always.
39. Building Envelope: Slab
Tuesday, November 18, 2008 39
- Continuous superinsulation under or around slab
- Basment: not part of PH, or TFA without solar heat gain (negative impact on calcs - difference to standard design)
can be remedied by not making the basement part of the PH envelope, putting it under the garage, or eliminating it
- Air-tightness
- EPS or foamglass
- Thickened-edge slab or slab on grade, basement outside of PH envelope
40. Building Envelope: Wall
Tuesday, November 18, 2008 40
- Continuous superinsulation with high R-21 to R80 depending on climate and location
- Clearly defined and protected air-tightness layer and water separation plane (any good building)
- Vapor barrier: protected (inside wall), inside exchanges moister with inside, outside with outside, perm rating at exterior 5x rating on interior
- In Minnesota: double wall construction likely
- Still stick-framed, or prefab, or SIP, or combinations
41. Building Envelope: Window
Tuesday, November 18, 2008 41
- American product not enough performance (R-value, air-tightness)
- Fully gasketed for air-tightness
- 1-3/4” triple-pane vs. 3/4” double-pane
- Centered in wall assembly for thermal performance, thermal bridge free installation
- Exterior sill: longevity, does not catch water like nailing flange
42. Building Envelope: Roof
Tuesday, November 18, 2008 42
- Continuous superinsulation: R-38 to R120 depending on location
- Air-tightness
- Similar to standard roof, or attic (venting, condensation issues)
43. Thermal Bridge Free
Construction
Source: PHI 2006
Tuesday, November 18, 2008 43
What is a thermal bridge? Two building parts of dramatically different temperature meet. (Cantilever at deck or balcony, uninsulated building element, etc.)
- Avoid condensation and mold (best practice on any building)
- Thermography can identify problem areas
- proper window installation without thermal bridges
Comes into play when retrofitting, hence exterior insulation package (talk about benefit)
44. Air-Tightness
Tuesday, November 18, 2008 44
- 25% of energy loss in existing buildings
- All joints sealed
- Blower-door test is field testing
- Find imperfections during construction, fix before dw and trim go up
Should be done in standard construction. Misses here account for most mold issues. Not so much of an issue with PH because of the amount of insulation used. PH is safer.
45. Energy Recovery
Ventilation
Tuesday, November 18, 2008 45
A must for any tight building!!!
- High-efficiency recovery ventilator
- Air-filtration
- Proper sealed ducting and noise cancelling measures (dampers)
- Main distribution system (fresh air and heat)
- Humidity control (mold issue)
46. Space Heating
Source: PHI
Tuesday, November 18, 2008 46
Mostly by internal heat gains and solar heat gains - rest is backup source (solar, electric, gas, wood, a bunch of friends, candle) to radiators, etc.
Again, integrated approach: Use same source for DHW and space heat for example.
Simplified system, less “moving parts”
In addition to using passive solar gain, Passivhaus buildings make extensive use of their intrinsic heat from internal sources – such as waste heat from lighting, white goods (major
appliances) and other electrical devices (but not dedicated heaters) – as well as body heat from the people and animals inside the building. Together with the comprehensive energy
conservation measures taken, this means that a conventional central heating system is not necessary, although they are sometimes installed due to client scepticism.
Instead, Passive houses sometimes have a dual purpose 800 to 1,500 Watt heating and/or cooling element integrated with the supply air duct of the ventilation system, for use during the
coldest days. It is fundamental to the design that all the heat required can be transported by the normal low air volume required for ventilation. A maximum air temperature of 50 °C (122 °F)
is applied, to prevent any possible smell of scorching from dust that escapes the filters in the system.
The air-heating element can be heated by a small heat pump, by direct solar thermal energy, annualized geothermal solar, or simply by a natural gas or oil burner. In some cases a micro-
heat pump is used to extract additional heat from the exhaust ventilation air, using it to heat either the incoming air or the hot water storage tank. Small wood-burning stoves can also be
used to heat the water tank, although care is required to ensure that the room in which stove is located does not overheat.
Beyond the recovery of heat by the heat recovery ventilation unit, a well designed Passive house in the European climate should not need any supplemental heat source if the heating load is
kept under 10W/m² [16].
Because the heating capacity and the heating energy required by a passive house both are very low, the particular energy source selected has fewer financial implications than in a
traditional building, although renewable energy sources are well suited to such low loads.
47. Simplified Mechanical System
“Magic Box”
Source: viessmann.com
Tuesday, November 18, 2008 47
Goal: get all-in-one solution to market in US.
48. Lighting and Appliances
Tuesday, November 18, 2008 48
To minimize the total primary energy consumption, low-energy lighting (such as compact fluorescent lamps), and high-efficiency electrical appliances are normally used.
Buy the most efficient appliances you can afford.
Use induction cooking, recirculating vents.
Can work with gas and exhaust, fireplaces - complicates things - is contrary to integrated design approach
49. Alternative Energy Sources
Tuesday, November 18, 2008 49
Donʼt 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
50. Predictable Outcome &
Quality Control
Passive House Planning Package
(PHPP)
• An Excel-based steady-state
energy design program
• Extremely detailed
• Calculations are transparent
and customizable
• Field testing
• Site supervision by Passive
House Consultant
Tuesday, November 18, 2008 50
How do we guarantee the result?
- Contractor training
- Extremely detailed design drawings
51. Passive House Certificate
Tuesday, November 18, 2008 51
The result!
All field testing successful, plans, documentation and PHPP submitted and approved. Certificate issued.
Home ownerʼs instruction (mandatory) and written manual (mandatory)
Building will be listed on the PHIUS website
53. Passive House Institute U.S.
(PHIUS)
• Certification
• Training
• Resources to Designers, Builders, Consultants
• Passive House Alliance
Tuesday, November 18, 2008 53
NEW CHAPTER!
- Official U.S. affiliate of the PHI in Germany, located in Urbana Illinois, earlier reference (coincidence)
- Issues the PH certificates in the U.S.
- Trains PH consultants
- Resource for Designers, Builders, Consultants
- Initiator of the Passive House Alliance
54. Passive House Alliance
• Passive House Planners & Consultants
• Passive House Builders
• Passive House Suppliers
• Initial Goal: Build a Passive House in each
climate zone in the continental U.S.
Tuesday, November 18, 2008 54
55. Smith House - Urbana, IL - 2003 - e-colab (first built in the U.S.) - Zone 3
Tuesday, November 18, 2008 55
What are built projects in the U.S.? - Book coming out in November: Mary James and Low Carbon Productions to publish Building Solutions for a changing Climate - Passive Houses in the
United States
56. Biohaus - Bemidji, MN - 2005 - Stephan Tanner (1st cert’d. in the US) - Zone 1
Tuesday, November 18, 2008 56
57. Fairview I: Affordable Housing Project - Urbana, IL - 2006 - e-colab - Zone 3
Tuesday, November 18, 2008 57
58. Fairview II: Affordable Housing Project - Urbana, IL - 2008 - e-colab - Zone 3
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selling for about $100 SF!
59. Tahan Residence - Berkeley, CA - 2008 - Nabih Tahan - Zone 4
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60. Cleveland Farm - Martha’s Vineyard, MA - 2009 - e-colab - Zone 2
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61. Isabella Eco Home - Ely, MN - 2009 - Nancy Schultz - Zone 1
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62. Stanton Residence - Champaign, IL - 2009 - e-colab - Zone 3
Tuesday, November 18, 2008 62
63. Built examples
• Single Family Detached Homes
• Row Houses, Town Homes
• Multifamily Buildings
• Mixed Use Buildings
• Office Buildings
• Schools
• High Rises
• Solar Decathlon Project
• Fire Station
• Deep Energy Reduction Retrofits
Tuesday, November 18, 2008 63
as seen in the beginning
64. Passive Houses in Europe
Passive House construction has grown exponentially in
Germany and Austria and continues with that trend.
Over10,000 passive house units had been constructed by the
end of 2007 and are inhabited all across Europe
Tuesday, November 18, 2008 64
All projects are listed on the PHI website. US projects will be listed on PHIUS website.
Cepheus: Cost efficient passive houses as european standard - pilot program (book). book (out of print)
65. Tuesday, November 18, 2008 65
First Passive House in urban setting. First in Twin Cities. Affordable Housing.
PH design lends itself well to affordable housing:
- low and predictable operating cost
- high survivability (doesnʼt cool off)
- empowerment through design (donʼt 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.
66. Benefits
• Economy: Cost savings to the homeowner
• Energy: Significant conservation
• Environment: CO neutrality in reach 2
• Health: Improved indoor environmental quality
• Comfort: Temperature, humidity, noise
• Durability: Reduced maintenance (passive approach)
• Value: Best product, arguably - “green sells”
• Conscience: Most efficient standard available today
➡ Quality of life
Tuesday, November 18, 2008 66
Economy: Significant conservation and improved performance = cost savings to the owner
Up to 75% savings on source energy (pending household use pattern), e.g. reduced utility bills (in Twin Cities, as much as $2,500 year or more in utility savings for
an average sized residence)
Potentially reduced homeowner’s insurance (due to reduced mechanical system and quality construction)
Benefits of energy eficiency mortgage
Federal tax credits, local utility company incentives (as applicable)
Ecology Energy: Significant conservation and improved performance = significantly reduced environmental impact
Significantly less energy consumption, smaller CO2 footprint
Likely in use and maintained longer than average building
Less likely to need retrofit, reduction in energy used for construction and materials
Can be “fueled” by virtually any power source
Easier to “fuel” with renewable energy sources, cheaper to outfit with appropriately sized renewable energy sources
High survivability, indoor air temperatures typically do not drop below 50 deg. F even when unoccupied
Crisis proof
Health: Improved indoor environmental quality = improved health
Guaranteed air-exchange 24/7—365 days a year
Tempered air, controlled humidity
Studies show less potential for asthma, allergies, sickness
Less drafty
Indoor surfaces are near room-temperatur, virtually no radiant heat-loss potential
Improved daylighting and solar exposure
Comfort: Superinsulated building envelope = high level of comfort
Indoor surfaces are near room-temperatur, virtually no radiant heat-loss potential
Guaranteed air-exchange 24/7—365 days a year, reduced exposure to odors
Extremely quiet inside due to superinsulation and high-performance windows
Durability: High quality planning and construction = extremely durable building
Quality-controlled construction and energy modeling, 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”
67. Zero Energy and
Carbon Neutrality
• Zero Site Energy: Energy produced on site = energy
used on site
• Zero Utility Bill: Produce enough energy on site to
offset the cost of all utility bills
• Zero Source Energy: Energy produced on site = primary
energy used at provider to deliver site energy
• Carbon Neutrality: Energy produced on site offsets
CO2 equal to CO2 used in primary energy production at
provider to deliver site energy
• Carbon Offset and Net Positive Energy: Offset
more CO2 than produced at provider—produce more
energy than used at provider to deliver site energy. Offset
energy-obsolete buildings
Tuesday, November 18, 2008 67
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.
68. Passive House Metrics
• Space Conditioning Energy Use (Heating/Cooling)
≤ 15 kWh/m yr (4,750 BTU/ft yr) 2 2
➡ U.S. housing stock average is approximately
175 kWh/m2 yr (58,580 BTU/ft2 yr)
up to 90% + improvement = leapfrog approach
• Air Tightness: n50 ≤ 0.6 ACH (0.1CFM/ft2)
➡ U.S. typical is 2.0 - 5.0 ACH
significant improvement = leapfrog approach
• Total Primary (Source) Energy Use
120 kWh/m yr (38,000 BTU/ft yr; 11.1 kWh/m yr)
2 2 2
➡up to 75% + improvement = leapfrog approach
Source: PHI, U.S. Energy Information Administration
Tuesday, November 18, 2008 68
Tech specs for those who are interested. This will be part of an advanced talk!
My house, 1927 2x4 standard construction with insulation: about 45kBtu
About 25% of heat-loss in the average home is due to leck of air-tightness
PE can be directly linked to CO2
Questions?
69. Retrofits
Yes, we can!
Up to 80% reduction in space-conditioning
energy (heating and cooling)
Tremendous nation-wide energy-savings
potential for existing building stock
Overcome obsolescence
Tuesday, November 18, 2008 69
70. TE Studio Passive House
Building design for new construction, remodels, additions
Energy optimizations, building analysis, consulting
Tuesday, November 18, 2008 70
Member Architecture Institute of America, Passive House Consultant, Adopter Architecture 2030 Challenge, Member USGBC (LEED),
71. beautiful, resource-efficient buildings
Tim Eian, assoc. AIA
Passive House Consultant
TE Studio, Ltd.
3429 Benjamin St. NE
Minneapolis, MN 55418
www.timeian.com
612-246-4670
tim@timeian.com
Blog: www.timeian.com/blog
Tuesday, November 18, 2008 71
Thank you for your time and interest. Greatly appreciate it. Thanks Oram for inviting me.