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Green Building News

A Petition Strives to Defend a Certain Definition of ‘Passive House’

A newly launched petition is encouraging PHIUS to to use a different name for its building standard and certification program

Many areas of the U.S. have climates that differ from that of central Europe. PHIUS has compared PHPP modeling and actual performance of certified projects. For a certified house in Salem, Oregon, PHPP modeling and measured results (over a year’s time) came in reasonably close, according to PHIUS executive director Katrin Klingenberg. Climate conditions in a relatively small portion of U.S. – the Northwest coastal region – are similar to those in Europe.
Image Credit: Passive House Institute U.S.

UPDATED 4/5/2012 with new blog links

Product names, program names, brands, and logos can be potent symbols of identity, so much so they’re often at the center of all kinds of marketing initiatives, corporate litigation, and cultural iconography. For people in the building industry, the term “passive house” – or Passivhaus, as we call it here – has come to mean a specific performance standard, and some say that if the criteria behind the standard are loosened to accommodate, say, climate conditions, a name other than Passive House (or Passivhaus) should be used.

That is the core idea of a petition that has been circulating on the Web since March 16 via SignOn, a petitioning tool sponsored by civic action group Hayden Robinson, an architect and certified Passivhaus consultant based in Seattle, launched the petition to suggest to Passive House Institute U.S. – which has been examining data from 100 PHIUS-certified projects and fielding comments from the building community about possibly relaxing the Passivhaus standard for some projects in extremely cold climates – that the group’s initiative, while worthy, should proceed with a name other than Passive House.

Multiple standards would create confusion

Here’s the text of the petition: “The Passive House building energy standard is widely recognized in North America and internationally. In the United States, the standard is used by hundreds of businesses and professionals, and its criteria are maintained by a number of certifying agencies offering services across the country. In its blog post, ’15kWh is dead. Long live 15kWh,’ PHIUS publicized a plan to create its own certification criteria and promote them using the Passive House name. PHIUS’s desire to innovate is commendable, and the larger conversation around potential improvements to the Passive House standard is healthy; however, having multiple standards competing under the name Passive House would create confusion and controversy. We therefore ask PHIUS to distinguish its program by giving it a distinctive name.”

Several of those who signed the petition are in Western Europe, a few are in the U.K. and Canada, and at least one is in Australia.

What gets to define “passive house”?

In their accompanying comments, most of the signatories seem to have no problem with PHIUS’s plan to modify criteria for the colder parts of North America, though they agree with Robinson’s contention that, should PHIUS modify its criteria, marketing the revised standard as “Passive House” would create confusion.

“ ‘Passive House’ is not a trademark or brand, but it does have a recognized meaning internationally and in the U.S.,” wrote Greg Duncan, an architect and certified Passivhaus designer based in Brooklyn, New York. “I believe that if PHIUS starts certifying buildings that do not meet this standard, they should use a different term.”

Katrin Klingenberg responds

PHIUS director Katrin Klingenberg told GBA she regards the petition as a “pretty normal response to our proposal for change” – a response, she said, that stems in part from misunderstandings about PHIUS’s study of building science and building performance as it relates to climate zones in North America.

“We haven’t been doing our best to communicate what we’re doing more clearly,” she said, noting in an e-mail that PHIUS’s data analysis “will address climates that are very different from the central European climate. Some climates might see a slight relaxation in the annual energy target (Duluth, MN, very cold), some will see a tightening (San Francisco, CA, much milder). It only makes sense to not make Passive House cost-prohibitive/impossible in very cold climates.”

Klingenberg also wrote, “Modifications will be in line with critiques of Passive House from leading building scientists and energy experts in North America like John Straube, Marc [Rosenbaum], Martin [Holladay], etc.”

Klingenberg pointed out that in dry, sunny climates of the sort found in New Mexico, hitting the annual energy target could lean less on superinsulation and more on the output of a solar thermal system.

“Modification doesn’t change the core value of PH,” she wrote, “it only makes it more accessible and cost-effective, and enhances its chance to become mainstream (without compromising comfort and envelope). It makes it the best it can be.”

Discussion heats up in the blogosphere

Several bloggers have chimed in on this dispute, including:


  1. fjW6mU4wNU | | #1

    Give it its own name.
    We’re talking about a technology. It’s bound to either evolve or be replaced. As many have pointed out, cost optimization is key. I'm an architect, not a researcher, so I look to the folks at LBNL, ORNL, RMI, GBA, PHIUS, and PHI to figure out what optimum is. And I hope to still be practicing when much better ideas come along.

    I appreciate PHIUS’s initiative in developing a new standard. I just hope they will have mercy on us all and give it its own name. There are multiple organizations offering PH certification services in North America: PHI Darmstadt, PHIUS, PHAcademy, CanPHI, and more on the way. It would be chaos to have different agencies establishing conflicting PH criteria. And creating disagreement about exactly what the standard is risks making the whole PH community look inept.

    The current PHIUS plan seems like a PR nightmare. It’s like starting a new car company and calling it ‘Toyota’; it wouldn’t matter how good the cars were, no one would take them seriously. Why risk marginalizing the PHIUS program as "fake Passive House" or “Passive House Lite”, and end up spending a bunch of time explaining a choice of terms? Why not give their program its own name, promote it as better-faster-smarter, and allow it to stand on its own merits?

    Of course, this could be making a mountain out of a nothing. Folks like Marc Rosenbaum and Thorsten Chlupp seem to be focused on making great buildings, not on worrying about labels.

  2. GBA Editor
    Martin Holladay | | #2

    Response to Hayden
    As you know, the solar pioneers of the late 1970s and early 1980s went through the same emotions you are now experiencing when Wolfgang Feist announced a new standard in the 1990s, and decided to call it "passive house."

    When all is said and done, it's the houses that matter -- and the utility bills at the end of a year's residence -- not the label.

  3. fjW6mU4wNU | | #3

    Response to Martin
    Good hearing from you Martin,

    The name is almost great. It’s just the “passive” and “house” parts that are unfortunate.

    Calling it passivhaus back in 1990 seems like a mistake to me. And that was compounded when the standard was formally introduced to the U.S. as passive house in the 2000's. Maybe it's only me, but the passive solar/passive house thing already seems confusing enough without alternative standards calling themselves “passive house".

    I agree, in the end, performance is what matters.

  4. GBA Editor
    Martin Holladay | | #4

    Response to Hayden
    Those are well-crafted sentences: “The name is almost great. It’s just the ‘passive’ and ‘house’ parts that are unfortunate.”

    How true!

  5. Mike Eliason | | #5

    i wonder if part of the
    i wonder if part of the response stems from folks that don't like the monopoly PHIUS seems to be setting up with regards to certification, training. this is further compounded by ridiculous lawsuits, jockeying, and confounding beratements (public and private) of consultants and advocates that don't 'toe the line'.

    the UK has several bodies that can certify a passivhaus. they meet regularly to discuss certification issues, even though they're technically 'competitors'. why is PHIUS afraid of similarly open and legitimate competition?

  6. Bronwyn Barry | | #6

    My Stanford-Degree-Equivalent
    The issue at focus here is not PHIUS itself, but about maintaining clarity. A while back Stanford started building to its own green standard, calling it 'LEED-equivalent.' ( The joke went round that Junior College's could now issue 'Stanford-Degree-Equivalents.' It doesn't take a Stanford-Degree-Equivalent to see where this might lead us...
    The petition request looks very simple (and is impressively respectful and polite) : if PHIUS wants to modify the Passive House Standard, they should simply give it another name.

  7. wjrobinson | | #7

    New and Improved!
    Like Tide, update PHIUS. I agree with the name change petitioners.

    Suggestion for names, let's name this and move forward people.

    My suggestion;


  8. fjW6mU4wNU | | #8

    Response to Bronwyn
    The LEED example is good one. In the Pacific Northwest we have our choice of programs: Passive House, Living Building Challenge, Built Green, Energy Star. If all of those programs called themselves “LEED”, the term would be meaningless, and no one would bother.

  9. user-1101118 | | #9

    what's in a name?
    LEED has subcategories.....LEED for commercial, LEED for homes, LEED for remodels, etc. These subcategories don't seem to dilute the LEED standard and what it represents IMHO. It acknowledges that different scenarios require different strategies.

  10. 4y23MuNF7N | | #10

    LEED sub-categories

    LEED has subcategories.....LEED for commercial, LEED for homes, LEED for remodels, etc. These subcategories don't seem to dilute the LEED standard and what it represents IMHO.

    The quoted sub-categories seem to show a differentiation based on type of building. Is there also a differentiation by location of building ?

    LEED for Fredericksburg, LEED for Fairbanks, LEED for Flint...etc.

  11. fjW6mU4wNU | | #11

    Response to Peter
    Clearly, certification programs can have different classifications. LEED Platinum, Gold, Silver. Minergie-A, Minergie-P, Minergie. In the Passive House case, there is an established standard, in widespread use in the U.S., with criteria developed and maintained by the Passive House Institute. And then there’s PHIUS developing a competing standard and wanting to promote it under the same name. That’s appropriation, not competition.

    I want to be clear. I encourage PHIUS to develop its standard; if they come up with a better one, it will benefit us all. The petition’s only point is that they should give their program its own name.

  12. Katrin Klingenberg | | #12

    Thank you!

    Thank you very much for your article. I understand that people might feel uneasy about modifications. Probably more so to those who have had little or no practical experience, which is clutch. Hayden Robinson, Mike Eliason and Bronwyn Barry, who expressed their opinions here, are to my knowledge in that group of consultants who have not had the opportunity yet to complete a Passive House project. I remember well, I would have felt the same before I completed my first one in 2003.

    More on PHIUS position on my blog here:

    Again, thanks to all who contribute to constructive discussions!

  13. fjW6mU4wNU | | #13

    Response to Katrin
    Let me make clear, I am not against modification. I support PHIUS in creating its own performance criteria – as the petition states, “PHIUS’s desire to innovate is commendable, and the larger conversation around potential improvements to the Passive House standard is healthy.” But it would be counterproductive for PHIUS to claim the name of an established and widely recognized standard as its own. The petition’s only request is that PHIUS give its program its own name.

    As for my resume, I’m a licensed architect and have been hired as a Passive House consultant on a number of projects; some have been built to the Passive House standard, some have not. At the invitation of PHIUS’s director: I lectured at the PHIUS 2009 national conference; served on the founding board of directors of PHIUS’s Passive House Alliance, where I was elected its first president; and have taught PHPP and THERM for PHIUS’s Consultant Training Series. I was the founding president of Passive House Northwest and a founder of the American Passive House Network.

    I should add that the jabs at Bronwyn Barry and Mike Eliason were uncalled for. Both are respected figures in the Passive House community; other consultants turn to them with questions on difficult technical issues. One of the joys of this work is that it takes a team – not just clients, architects, and builders, but also engineers, product designers, manufacturers, and distributors. I am grateful for the contributions made by all of them.

  14. user-668047 | | #14

    In support of the petition
    in support of Hayden's points and the intention of the petition, I do not have an issue with PHIUS creating a low energy model that uses the Passive House Standards as a basis for their own modifications. What I do object to, and the intention of the petition, is to request that PHIUS not confuse the marketplace by calling this revision of the Passive House standard a Passive House. As it is intended to be different than the established Passive House standard, then it is different, and needs to be differentiated as such by branding it as something different. There is already a well established certification process for certifying buildings that meet the Passive House standard.

    I support PHIUS calling their standard PHIUS +, which seems to make sense to me. It is a standard developed by PHIUS. If a house or building is a PHIUS + House, then lets be clear that it is not a Passive House, which has a long history of being defined by the Passive House Institute, where the concept was refined, studied, and developed as a standard over the last 20 years. A PHIUS + House would therefore not be discussed as a Passive House, but simply called and discussed as what it is, a PHIUS + House.

    It reminds me of the times when institutions were referring to their buildings as LEED equivalent. It was and would be a confusion to the market to allow this to happen. It would be like my saying my MIT Masters in Architecture degree is also a Stanford Equivalent degree. Only Stanford has the right to grant me a Stanford degree, as does the USGBC retain the right to call a building a LEED building. Similarly, it seems to me that only a building that meets the long established and well documented Passive House standards can call itself a Passive House building.

    Please, lets keep the focus on the issues, not the people. When Katrin chooses to suggest that certain people in the community are not really familiar with the Passive House issues, let me remind everyone that the people she called out are people who have attended multiple national and international conferences, have helped create local Passive House conferences, have consulted on and advised others on their Passive House projects, have lectured about Passive House, have served as board members of local Passive House communities for years, have been actively and completely involved in the Passive House movement for years, and are passionate about preserving the brand and the name of something they strongly support for the sake of planet's well being. I resent Katrin's denigrating people's credentials as if so she has a corner on the wisdom, and avoiding addressing the issue at hand. The simple request is for PHIUS, if they chose to change the Passive House standard, to choose a different name and branding for what they are wanting to certify.

    I notice in Katrin's blog that she now refers to Pasive House in lower case, although for years we have refered to it in upper case, which is my preference. I believe Passive House is not like a saying low energy or plug-in, as the latter do not have standards and certifications associated with them, and keep the two separate.

  15. Bronwyn Barry | | #15

    Looks like a simple petition to encourage a new name has turned into the naming of names. (AJ Builder, Eric and Peter I'm sorry you weren't invited to the party - we are quite good company!) The name for that debating technique is Intimidation, or Bullying.
    It would be great to keep the focus on the topic at hand, which is simply a call to give a new standard a new name. I hope others will not feel intimidated to sign.

  16. [email protected] | | #16

    Response to Katrin
    There are now 311 Certified Passive House Consultants listed on the PHIUS website. There are thirty-four certified and pre-certified Passive House projects listed. Of those projects, twenty-five--by twenty-two different CPHCs--have been built. Kat, are you saying you think that the other 289 Certified Passive House Consultants (92% of us) who haven't yet had a Passive House built don't have a dog in this show?

    That, it seems to me, would not be a wise or popular stance for the head of PHIUS. It distracts from the real and important discussion that is taking place now, and from the real progress that is being made with Passivhaus across the US. The position of Executive Director of Passive House Institute US, at this point in the Passive House movement, demands tact and professionalism, not just technical competence.

    Controversy does not instill confidence in a new direction. Cooperation and civil discussion does. That there might be disagreement between passionate people is not surprising (or even a bad thing!) depending on how that disagreement is handled. If it is "handled" by personal attacks by the head of the certifying body (PHIUS) on professionals who might be submitting projects to that body for certification (Hayden, Mike, Bronwyn), then that can not go well, and should not be tolerated by the Board of Directors of PHIUS.

    Setting that aside and returning to the discussion at hand, let me say, as others have said: I am in favor of regionally specific (by country) programs for Passive House. It simply makes sense, and will allow faster adoption of the idea, to have a Passive House program that dovetails with existing permitting, taxing and incentive structures for each country. And, yes, we have issues of latent moisture in the southern US that are not part of the discussion in Central Europe. And yes, I think there could not help but be better ways of modeling than the Excel-based PHPP. (I hold high hopes for both the "whole house" WUFI and for Graphisoft's Eco-Designer, a plug-in for ArchiCAD, which exports directly to PHPP.) For all those reasons, I support the direction PHIUS is taking. I am not, however, in favor of "relaxing the standard" nor am I in favor of calling the new standard "Passive House," and for that reason, I'll be signing the petition. That is *all* the petition is about: the name!

    I agree with Dr. Feist who said: "Passive House" describes a way of building. It is not a brand, nor is it copy-writeable. Calling the new standard PHIUS+ will be fine--it's headed that direction now. PHIUS+, like Minergie, Passivhauscentrum, etc, will all fall under the umbrella of "Passive House." One big happy family!

    I personally feel like I have a lot to learn from the 20+ years and 30,000 building experience of PHI and our European colleagues. I would prefer not to leave that behind with further feuding. Can't we all get along?

  17. GBA Editor
    Martin Holladay | | #17

    Mike Eliason chimes in
    Mike Eliason has just posted a blog entry commenting on this discussion. You can read it here: On Peti- & Certifica- tions.

  18. user-1113268 | | #18

    The House of Passive House
    Passive House standards vary across Europe. Both Passivhaus Institute sanctioned and independent Passive House organizations have various limiting values depending on their region. PHI itself prescribes a 20 kWh/m2 heating demand for those above 60 degrees latitude. But organizations in Scandinavia go further and have their own range of values for heating demand and primary energy, and even different ventilation rates.

    Reports for the Promotion of Passive Houses (PEP) suggest that by adjusting values in both colder and warmer climates, Passive House becomes more cost-effective and has a better viability for growth in those climates. Why the PHI is not officially promoting different values in Mediterranean regions is baffling.

    There is tremendous potential in expanding the market by making minor modifications to the standard in just a few regions. Otherwise, it may be that the market stagnates and Passive House doesn't realize its potential. The primary reason why Passive Houses are going up like wildfire in Europe is because of the governmental and financial support. Our situation is unique and demands a unique approach.

    Easing Minnesota and Canada to the 20 kWh value is not going to cause the House of Passive House to fall...get a grip! It will however, help instigate a campaign there that would jumpstart a revolution in building.

    I will not be signing the petition. My interest is in saving CO2, not in saving the Pope.

  19. GBA Editor
    Martin Holladay | | #19

    Lloyd Alter from chimes in
    Here's a link to Lloyd Alter's blog on this topic on Treehugger: A Plague On Both Their Passive Houses.

  20. 4y23MuNF7N | | #20

    Market Forces and Rapid Change

    The primary reason why Passive Houses are going up like wildfire in Europe is because of the governmental and financial support. Our situation is unique and demands a unique approach.

    No it isn't and no it doesn't.
    Some parts of Europe (which is an area of land off the East coast of America with a large and varied population and a very varied climate) have backed Passivhaus construction with local and central government support and funding. They have done so to ensure that enough new low-energy housing is built to even make a small difference. They have done it as they have because they appreciate the likelihood of this state of affairs occurring through market forces. Until all public and new-build housing in the US is obliged (yes, I am suggesting enforced zoning and planning, Federal money and higher taxes) to adopt stringent low-energy standards the 'green building revolution' will remain the navel-gazing preserve of the few who care.

  21. 4y23MuNF7N | | #21

    Who is 4y23MuNF7N
    The section of text above the "Subject" box on my computer correctly identifies me as Peter Hastings.

    Huh ?

  22. 4y23MuNF7N | | #22

    Truth in Advertising

    A PHIUS + House would therefore not be discussed as a Passive House, but simply called and discussed as what it is, a PHIUS + House.

    Am I missing something here? Is there a suggestion that an internationally-recognized standard is to be made less stringent so that houses which meet it can be made for less money and the concept is to be marketed as PHIUS PLUS?

    I know some architects believe that less is more but it's always going to be a hard sell for the general (i.e. house-buying) public.

  23. fjW6mU4wNU | | #23

    Response to ikoEZ8Kzu5, Re: Canada
    If you will humor me for a second, I want to get something off my chest: as a U.S. citizen, I cringe at the presumption of PHIUS’s plan to relax the PH standard for “the unique climate and market needs of… Canada.” I wish U.S. organizations would keep in mind that Canada is sovereign county with a demonstrated ability to create its own policies, a history of pioneering contributions to high-performance building technology, and its own Passive House organizations.

    Thanks for listening.

  24. Katrin Klingenberg | | #24

    Apologies and clarification
    First—let me apologize for personalizing this issue. Everyone who’s commented has done so because they’re passionate about passive house, and everyone’s voice is important. And I’m very sorry for suggesting otherwise.

    Second, Rob Harrison made some great points, and I'd like to take this opportunity to state more clearly our position on this issue and the petition.

    First, regarding Rob's quote of Dr. Feist: "Passive House" describes a way of building. It is not a brand, nor is it copy-writeable.

    We have always been in complete agreement with Dr. Feist's statement. We think the way of building is what matters. That way of building--superinsulation, airtight envelope, energy recovery ventilation, solar gain management, and high-performance windows--constitute the core of what passive house (or passivhaus) means.

    Rob also made a good point: Calling the new standard PHIUS+ will be fine--it's headed that direction now. PHIUS+, like Minergie, Passivhauscentrum, etc, will all fall under the umbrella of "Passive House." One big happy family!

    To expand, we are already calling our certification PHIUS+ because it adds a quality control and quality assurance component that is critical to the U.S market.

    With regard to Rob's excellent point about CPHCs having "a dog in the show." Once again, I apologize for personalizing the issue in my last comment. Besides being unfair, it didn't say what I intended to say. That is this:

    In fact, the idea of adjusting the passive building energy standard to climate and market realities is meant to recognize that CPHCs and builders across the country all have dogs in the show. And to recognize that rigidly adhering to a single number provides a disincentive to apply passive house -- as a way of building -- to reach the highest practical performance in their regions.

    This is something that no single CPHC working in a single region can see as well as we are privileged to experience. We've helped CPHCs wrestle with problems ranging from latent loads (humidity) in Louisiana to extreme cold (Alaska, Minnesota, Wisconsin, Maine). We've reviewed their plans and construction progress from start to finish. And we've seen first hand how different the challenges are, and how sticking to a single number will stop many designers and builders from adopting passive house as a way of building. This experience, we think, brings a responsibility to adjust the standard to climate needs. (And again, adjustment in many cases -- such as California -- probably will lead to a more stringent standard.)

    In other words, I think we agree on more than we disagree -- that passive house is a way of building, and we are all passionate about making that way of building a mainstream set of best practices in the North American building design and construction market. As my blog post ( explains, PHIUS+ is a particular certification, but it will be accomplished applying passive house as a way of building.

    Once again, my apologies for the earlier post, and thank you -- all -- for weighing in.

    Katrin Klingenberg

  25. fjW6mU4wNU | | #25

    Response to Katrin Klingenberg
    Thank you, Katrin. Apology accepted.

    Your comment eloquently summarizes PHIUS’s rationale for creating a new standard. I appreciate the organization’s willingness to call its program something other than Passive House and welcome it into the community of high-performance building standards. However, I am troubled by PHIUS’s continued appropriation of the term Passive House (or passive house, or Passivhaus, or whatever this week’s iteration is) as merely a generic way of building. Passive House, as well as referring to the mix of strategies refined by the Passive House Institute, IS an existing standard that is widely recognized in the U.S. and used by the certifying agencies that PHIUS competes with.

    Can you please clarify that PHIUS is creating a new, different standard and will not claim to alter the Passive House (passive house, etc.) standard? The controversy and confusion surrounding the matter are already harming both PHIUS and Passive House (see comments regarding certification posted at “On Peti & Certifica- tions” ( and continue to risk marginalizing PHIUS programs as controversial and “so-called Passive House”.

    Hayden Robinson, AIA

  26. [email protected] | | #26

    Response to Jesse
    Jesse Thomas makes an excellent point, and has helped me to clarify my thinking about this discussion. It's not "relaxing the standard" that bothers me as much as the US standard diverging from the standard of our European Passivhaus colleagues. I'd like to see the standards "harmonized" worldwide so that Passive House means the same thing *for the same climate* world-wide.

    I don't *know* what the different European standards are, or where they apply. Someone needs to make a comparison graph of PHI, Passivhuscentrum, Minergie, Minergie-P, Passivhaus above the 60th parallel, et al. Well, heck.... If someone can send me the data I will create the chart and post a link here.

    And Kat, thank you for your apology.

  27. fjW6mU4wNU | | #27

    PHIUS does not have the authority to alter Passive House
    There are many building performance standards, however Passive House is used internationally and maintained by the Passive House Institute. Minergie, developed in Switzerland, does not alter Passive House; it is an independent standard. Claims that the Swedes (Passivhuscentrum) recognize a relaxed version of PH are incorrect.*

    Regardless of the pros and cons of doing so, PHIUS does not have the authority to alter the PHI's universally agreed upon standard. If a regionally specific standard is called for, there are two options: either lobby the PHI, or opt for a standard other than Passive House.

    Passive House will not be the end of the road for energy performance programs and there’s room in the world for more than one standard. Call a Passive House a Passive House, call a PHIUS+ building a PHIUS+ building, call a Minergie building a Minergie building. And let the programs compete on there merits.

    *According to the Swedish Passivhuscentrum: “Passive House is a standard with a variety of requirements to be met in order that the building should be called passive. The basic requirement is that the building requires only 10 watts thermal input per square meter at 20 ° C indoors on the coldest days, defined by the design outdoor temperature. Additionally, the building must be air tight, it may leak max 0.3 l / s, sq turnover. at ± 50 Pa pressure difference. To achieve good comfort are also requirements for the components in a passive house. See specification for passive for more information.”

  28. user-1113268 | | #28

    RE: Authority
    Hayden, the excerpt you took from Passivhuscentrum is just an introduction. Look further and you find that they have two international and one Swedish.
    I also noted this on Katrin's blog, but will note here too for the clarity of all readers.
    The difference in standards is outlined in the following translated page.

    It is possible that the US can have two Passive House definitions that co-exist. And it actually could be a very healthy arrangement. There is precedent for this.

  29. Mike Eliason | | #29

    a few things from this


    a few things from this report...
    1. for northern sweden, they increased the heat load from 10W/m2 to 12W/m2 (14W/m2 if under 200sm) and waived the 15kWh/m2a space heat demand. I'm confused, it's still possible to hit 15kWh/m2a with a heatload of 14W/m2, no?
    2. they reduced electricity source factor from 2.7 to 2.0
    3. it seems the relaxation was done in part so folks could 'self-claim' - that is, it seems more prescriptive, and thus you could claim it's a PH.
    4. does ambition to 'harmonize the Swedish criteria for PH w/ international initiatives' mean they intend to make the northern standard stricter? (the opposite of the PHIUS proposal)
    5. the swedes allow garages to be included in their 'TFA'

  30. user-955869 | | #30


    The Swedes did not change the functional definition of a Passive House. The increased heat load is based on higher required ventilation rates and colder outdoor temperatures. A house in northern Sweden can be heated through the ventilation air alone at 14 W/m2. They also assume heating to 22C, not 20C. I don't want to get into the intricacies of the Swedish approach. The main point is that they retained the functional definition. In the Swedish text there is the conclusion: "The consequences are that the investment costs to meet the Swedish requirements are lower,
    but that energy costs will be higher." (thanks to Google translate)

    If you abandon the functional definition (or its approximations: 15 kWh/m2a and 10 W/m2), then there is no reason to use the term "Passive House".

  31. user-1113268 | | #31

    RE: FEBY report

    Seems that in the voluntary Swedish version, the heating demand value is ignored.

    Primary energy factor is estimated to be 2.0 because of the prevalence of Hydro and co-generation plants.

    Houses under 200 m2 get a 2 W/m2 (small house) buffer for heat load. Heat load is determined from sunny day temp. and cloudy day radiation.

    When I was at Passivhuscentrum in Alingsas, Sweden, John Helmfridsson told me that the climate data on Sweden that the Passive House Institute uses is not realistic. In real world situations, there is much less radiation, thus a higher heat demand than predicted.

    Most of what you and Greg says is, I think, correct. (The garage part is beguiling...I don't know where you got that or how that is calculated.)

    The FEBY report also emphasizes that the Swedish Passive House definition was responsible for "establishing Passive House on the market."

    Higher ventilation rates, lack of sun in early winter, different window technologies, different methods of construction, different funding structures, etc... Result: Different standard based on the same principle of reducing the peak heat load so that heat is distributed via the ventilation system.

  32. Mike Eliason | | #32

    the garage info was

    the garage info was from the passivhuscentrum criteria for certification, i'll email the link if i can find it again.

  33. fjW6mU4wNU | | #33

    Re: Sweden
    Jesse Thomas: I stand corrected.

    Greg Duncan: Thanks for bringing a bit of clarity to the confusion.

  34. fjW6mU4wNU | | #34

    Response to Jesse Thomas
    How would multiple competing definitions of Passive House be better than having distinct standards?

  35. user-1113268 | | #35

    Response to Hayden Robinson
    When viewing the potential of the Passive House movement holistically, ideas such as market expansion and market diversity may play an important roll. Expansion identifies untapped markets, while diversity recognizes the cultural, climatic variables.

    In your mind, one sacred standard of Passive House ensures a consistent quality product.....which has viability, but ultimately may fail in realizing market potential. On the other hand, a more flexible standard has the benefit of satisfying market diversity. Yet both can operate from a common definition of minimizing heating/cooling load.

    The benefit to having both standards is to help satisfy ideological differences, thus helping to maintain progressive movement. Also, together they may promote growth in the market exponentially through both competition and a linked reputation/lineage. In a sense, both standards (American and International), working independently, help to grow and inform each other.

  36. fjW6mU4wNU | | #36

    Response to Jesse Thomas
    Thanks for the articulate response, I enjoyed reading it. It seems like calling Passive House, Passive House and Minergie, Minergie allows and highlights diversity while avoiding confusion and making choice easier. Wouldn’t the same be true if PHIUS used a different term to describe their program? By taking the name of a standard that is already accepted in the U.S., and using that term for buildings they hope will be created under weaker PHIUS criteria, wouldn't PHIUS be creating less, rather than more, market differentiation?

  37. user-1113268 | | #37

    Response to Response to Jesse Thomas by Hayden Robinson
    Not sure Hayden. You may be right. But, I come back to the thought that we are two voices coming from polar opposite ideologies...yet we live and operate within 50 miles of each other. PH suits our climate rather well. But are we hearing voices from all viewpoints across the country?

    My problem with the petition is that it made a yes or no answer out of questions like...

    Does PHIUS have the right to alter the PH standard?
    Who has the right to alter the standard?
    Should the Passive House standard even be altered in America?
    Is the standard working for America?
    What part of the standard would be altered?
    Does this alter the definition of PH?
    What is the definition of PH?
    What is the goal of PH?
    Does the definition fit the goal of PH?
    Why is PH so important as a movement?
    Are you willing to give up the name of PH?
    Would a name other than PH be marketable?
    Is Germany interested in re-negotiations?
    Do we want to be independent from Germany?
    Can there be a truly international, democratic PH?
    Do we want an international, democratic PH?
    and so on....

    In my view, there is alot of discussion and decision making to be done in a very democratic way. Hopefully we can move deliberately, thoughtfully towards solutions without compromising the integrity of the whole movement.

  38. Bronwyn Barry | | #38

    For the record... and a response to Jesse
    Jesse - You've mined a long list of questions from what I understood as a single and very focused request: to give the new PHIUS+ standard a new name, in much the same way that 'Minergie P' has it's own name, yet remains associated with the Passive House concept. I was impressed with how Hayden was careful to remain supportive of PHIUS and their proposals to make adjustments to the Passive House Standard.

    The questions you raise however, are all excellent and each worthy of their own petition. It's clear from the hot debate this topic has elicited that they need to be discussed broadly, without fear of repercussions. We do need to practice the ability to disagree without taking things personally or maligning each other (politicians included!) On that note, I do want to acknowledge the apology issued above to myself, Mike and Hayden. It is appreciated.

  39. user882465 | | #39

    Response to Peter Hastings - Re: LEED Subcategories
    "LEED has subcategories.....LEED for commercial, LEED for homes, LEED for remodels, etc. These subcategories don't seem to dilute the LEED standard and what it represents IMHO."
    - Erik Lobek

    The quoted sub-categories seem to show a differentiation based on type of building. Is there also a differentiation by location of building ?

    LEED for Fredericksburg, LEED for Fairbanks, LEED for Flint...etc.
    -Peter Hastings 4C
    I don't have a position regarding the definition of Passive House, but felt I should point out that LEED most definitely DOES have subcategories for energy performance by location. LEED for New Construction references the ASHRAE 90.1 performance standard. Points are awarded based on the percent by which you exceed minimum performance requirements of that standard. ASHRAE has eight climate zones and the performance requirement varies depending upon the zone in which a building is located. So at least for the 19 possible points in Energy & Atmosphere Credit 1 in LEED 2009, where the number of points achieved is determined by modeled performance against the ASHRAE 90.1 minimum standard for a given climate zone, there are differing LEED standards.

    So I CAN see how there could be regionally determined standards for Passive House. That's not to say I'm advocating for that. But if you were to go back to passive solar design in the 1970s, the amount of thermally massive materials required for a passive solar home in Minnesota varied from what would be required in Arizona or California. Of course, the goal remained the same, to minimize or reduce the need for fossil fuel use.

    Bill Burke

  40. user-944275 | | #40

    it's way more complex than re-naming the standard
    With all due respect to the authors of the petition, there has been plenty of "chaos and confusion" with the standard just as it is. Enshrining it as such does not result in "clarity." CPHCs are smart enough to understand the need for changes and to be able to explain them to their clients and the general public. Keep in mind, the small portion of North America where a peak load of 10 W/m2 makes sense will still have that metric to achieve....

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