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Is This Building Passivhaus-Certified?

American and German certifying organizations disagree over whether this Canadian duplex, the Rideau Residences, meets the Passivhaus standard

Posted on Jan 27 2012 by Martin Holladay

UPDATED February 7, 2012 with a response from Wolfgang Feist

The first residential Passivhaus building in Canada is the Rideau Residences, a duplex at 279 Crichton Street in Ottawa. The building has impressive specifications: an R-70 foundation, R-50 walls, an R-70 roof, and triple-glazed low-eLow-emissivity coating. Very thin metallic coating on glass or plastic window glazing that permits most of the sun’s short-wave (light) radiation to enter, while blocking up to 90% of the long-wave (heat) radiation. Low-e coatings boost a window’s R-value and reduce its U-factor. windows. The building’s air leakage rate was tested at 0.58 ach50.

On November 22, 2010, the Passive HouseA residential building construction standard requiring very low levels of air leakage, very high levels of insulation, and windows with a very low U-factor. Developed in the early 1990s by Bo Adamson and Wolfgang Feist, the standard is now promoted by the Passivhaus Institut in Darmstadt, Germany. To meet the standard, a home must have an infiltration rate no greater than 0.60 AC/H @ 50 pascals, a maximum annual heating energy use of 15 kWh per square meter (4,755 Btu per square foot), a maximum annual cooling energy use of 15 kWh per square meter (1.39 kWh per square foot), and maximum source energy use for all purposes of 120 kWh per square meter (11.1 kWh per square foot). The standard recommends, but does not require, a maximum design heating load of 10 W per square meter and windows with a maximum U-factor of 0.14. The Passivhaus standard was developed for buildings in central and northern Europe; efforts are underway to clarify the best techniques to achieve the standard for buildings in hot climates. Institute U.S., an organization with headquarters in Urbana, Illinois, issued a document to the developer, Christopher Straka of Vert Design, certifying that the Rideau Residences met the Passivhaus standard.

Up until that point, the certification process had gone smoothly. But then the Rideau Residences story took a strange twist.

The certificate is challenged

One of the consultants involved at the early stages of the Rideau Residences project was Malcolm Isaacs, a civil engineer and founder of the Canadian Passive House Institute. Isaacs was eventually replaced by Ross Elliott, an energy consultant and the owner of Homesol Building Solutions. According to Isaacs, “I was the Passivhaus consultant on that project initially, but I was not involved in the construction of the house.”

Isaacs had partial knowledge of the project’s details — enough information, he felt, to bring a complaint to the Passivhaus Institut in Darmstadt, Germany. The essence of Isaacs’s complaint was that several as-built features of the Rideau Residences differed from the project documentation. In Isaacs’s view, these differences were serious enough to question the legitimacy of the building’s Passivhaus certification.

In a July 2011 e-mail to André Fauteux, the editor of a Canadian construction magazine called La Maison du 21e siècle, Isaacs wrote, “I repeated several times to Louise [Legault] that almost certainly this house does not come near the international PH Standard, and that this view is endorsed by the Passivhaus Institut in Germany, who are currently auditing it. … You can be sure that the Passivhaus Institut is treating this matter extremely seriously.”

Feist appears to endorse Isaac’s view

How seriously did Dr. Wolfgang Feist, the director of the Passivhaus Institut (PHI), take Isaacs's concerns? Very seriously, as it turns out — seriously enough to publicly accuse the Passive House Institute U.S. (PHIUS) of certifying buildings “without the requisite documentation.” Feist concluded that the certificate issued to the Rideau Residences was so unjustified that it was time to cancel all contracts between PHI and PHIUS.

In short, the certificate issued to the Rideau Residences was one of the causes of last August’s PHI-PHIUS divorce.

In his August 17, 2011 letter announcing the divorce, Feist wrote, “Evidence of PHIUS’s certification of Passive House buildings without the requisite documentation has threatened the integrity of the standard and forced PHI to terminate PHIUS’s status as an accredited Passive House Building Certifier.”

On October 5, 2011, Ross Elliott gave a presentation on the Rideau Residences at the GreenBuild conference in Toronto. He explained that the complaint filed with the Passivhaus Institut alleged that there were several possible problems with the project:

  • A thermal bridge at the brick ledge wasn’t properly accounted for.
  • The solar heat gainIncrease in the amount of heat in a space, including heat transferred from outside (in the form of solar radiation) and heat generated within by people, lights, mechanical systems, and other sources. See heat loss. calculations failed to account for a pine tree that partially shades some of the building’s lower windows during the winter.
  • The project’s HRVs and windows hadn’t been certified by the Passivhaus Institut in Germany, rendering their specifications suspect.

For North American Passivhaus designers, this last issue has been a bone of contention for some time. According to Mike Eliason, a designer at Brute Force Collaborative in Seattle, Washington, “Utilization of certified Passivhaus components ensures the values entered into PHPP are verified and accurate. This can be crucial and have significant implications when it comes to HRV/ERV(ERV). The part of a balanced ventilation system that captures water vapor and heat from one airstream to condition another. In cold climates, water vapor captured from the outgoing airstream by ERVs can humidify incoming air. In hot-humid climates, ERVs can help maintain (but not reduce) the interior relative humidity as outside air is conditioned by the ERV. efficiency. If the product is not certified, 12% must be deducted from the heat recovery efficiency. For a (currently) uncertified product like the UltimateAir Recouperator, which claims 95% efficiency, we can only utilize 83% in PHPP.”

Katrin Klingenberg defends the certification

After Dr. Feist accused PHIUS of issuing an undeserved certification, Katrin Klinenberg, the director of PHUIS, defended the process used to certify the Rideau Residences.

In an August 19, 2011 letter to Feist, Klingenberg wrote, “We were asked [by PHI] to provide all the drawings and documentation for the certification and we were told after an unusually quick review of what we submitted, that the PHI had concluded that this project is not anywhere close to the standard. … The [heat-recovery] ventilator data turned out by PHI’s own rules to be just fine, just as we had it entered in the PHPP.”

Klingenberg continued, “Now 8 months after we initially certified the project, the window company finally agreed upon our insistence and inquiries to provide the actual THERM files for the window brand, which they previously had refused. The window values were slightly worse than we had initially assumed. … PHI has never provided us with the accurate calculation method for window frames even upon inquiry (I am assuming it is to protect their product certification as proprietary) so we were left like everybody else to make an educated guess as best as we could based on the information that was available to us last year.”

Concerning the brick ledger, Klingenberg wrote, “We had been told that the angle holding the brick veneer would be thermally broken with aerogel. That had not been documented in the drawings but communicated verbally. This was not implemented on site. … This pointed to the need for more standardized on-site quality assurance and third-party field verification, which we have actively created with the PHIUS+ program.”

Klingenberg noted that it is difficult for a certifying agency to verify all of the specifications submitted by an architect. “The certification protocol currently does not require proof of exact shading calculations. … The experience here shows that higher insolationAmalgamation of the words “incoming solar radiation” that means the total amount of solar energy that strikes a given surface in a given time. It is commonly expressed in kilowatt-hours per square meter per day. in North America needs a more strict quality assurance requirement and we would like to suggest adding to the blower door test and commissioningProcess of testing a home after a construction or renovation project to ensure that all of the home's systems are operating correctly and at maximum efficiency. protocol the requirement for a solar pathfinder study, to avoid these kinds of problems.”

In a January 5, 2012 e-mail to André Fauteux, Klingenberg summed up the situation: “Documentation was all there. Except the altered detail which was communicated verbally and not confirmed on site as there is no provision for that type of Quality Assurance from the certifier. We have to rely on the architect, builder, etc. And aside from that, this detail was really minor in terms of lessening the performance. At that point we are really talking peanuts. They are prejudiced and think that there can't be a good North American ventilator (they want to sell the expensive European stuff!), so they assumed we were using the wrong values because they were meeting their specs. Turns out, indeed, Lifebreath is meeting it. So, their beef was wrong. Last and most important issue, that did kick the project out of the certification range, is entirely on them. There is no site verification if the shading assumed in the PHPP is actually correct (solar pathfinder etc not required). In this case, if it had been required, we would have caught the mistake in the theoretical shading assumptions.”

Duking it out in public

This public dispute raises several questions, including these:

  • Is the skepticism concerning the performance of Canadian materials that aren’t certified by the Passivhaus Institut reasonable or biased?
  • Could any Passivhaus building in any country stand up to similar under-the-microscope scrutiny by someone looking for minor flaws or discrepancies?

Once the dispute between PHI and PHIUS became public, Elliott quickly realized that the building under discussion was the Rideau Residences. Referring to the buildings mentioned in the public letters, Elliott wrote, “Might that be the PHIUS-certified Canadian house Malcolm Issacs has declared definitively and publicly on several occasions (including recently to very influential Canadian green building media trying to promote PH) was ‘nowhere near Passive House’? The one he flew to Germany to complain about and re-open eight months after Katrin passed it in November 2010? … Is it about solid, impersonal spreadsheet numbers adding up correctly, or about personality clashes and intransigent opinions on how someone should build and what products they should be allowed to use? Are we learning from or competing against each other?”

When I spoke to him recently, Malcolm Isaacs told me, “We did ask PHI some questions. I was the person who raised these questions, because the building was aiming to be the first passive house in Canada, and we needed to be sure that it was. I have been in contact with PHI on this, and they have not said anything yet.”

Isaacs also said, “I have managed to ruffle a few feathers.”

The building is still certified

Editor André Fauteux wrote, “We contacted Wolfgang Fiest, the founder of PHI and the author of the [August 17] letter, and asked him whether or not the Ottawa duplex satisfied the requirements of his organization, and if the certification that had been issued to it would be rescinded. Dr. Feist has still not answered our questions.” [Update: On Februrary 7, 2012, Feist responded to questions about the Passivhaus certificate awarded to the Rideau Residences; his response has been included at the end of this article.]

Since PHI has publicly disassociated itself from PHIUS, Dr. Feist has apparently washed his hands of any involvement with PHIUS’s certification decisions. Since PHIUS's certification procedures were found wanting by PHI, none of PHIUS’s certifications meet international standards anymore. As a result, the certification issued to the Rideau Residences — a type of certification that is recognized only in the U.S. — still stands.

The developer of the Rideau Residences is Christopher Straka of Vert Design, a design/build firm in Ottawa. As far as Straka is concerned, his building is Passivhaus-certified. Straka told me, “I have never received a phone call or letter indicating that the Passive House certification for the building has ever been challenged.”

When discussing the way his building was challenged, Straka takes the high road. “The Rideau Residences were a great learning experience,” he said. “Overall, a bit of controversy behind the curtain doesn’t hurt anyone as long as the questions are positive, with the mission of getting better building methods.”

Local versus imported materials

One of the questions raised by l'affaire Rideau is this one: Is it better to use local materials, or materials that have the stamp of approval of the Passivhaus Institut in Germany? Isaacs and Straka have different answers.

“We cannot use Canadian HRVs in Passive Houses, simply because they perform so poorly — a sad truth,” Isaacs wrote. “I installed a highly rated VanEE [heat-recovery ventilator] unit in my own house (‘80% efficiency’). I have measured the supply air temperature coming into the house when the exterior is at -10°C, and it is around 5° - 7°C. For the Paul [HRV] unit we used in Montebello [a different Passivhaus project in Canada], the supply air is guaranteed to be at 17°C. This makes a huge difference to annual energy use!”

Taking an opposing position, Straka says, “I do believe that Canadian-made construction materials and systems can be combined to create Passive House buildings. … I believe that limiting the selection of components a project team can use (to those recommended by the Passivhaus Institut) will stifle innovation and limit the adoption of the Passive House standard in Canada.”

Straka told me, “I believe that we can build better buildings by building local buildings, with materials sourced from your region or country. That is better than reaching overseas. That’s not to say there aren’t great products produced overseas. But we should strive to be getting our materials by driving across town instead of getting materials from 6 time zones away.”

One more twist

When researching this dispute, André Fauteux sent an e-mail to Katrin Klingenberg, asking several questions about the Rideau controversy. In her e-mailed answer to Fauteux, Klingenberg commented on an unrelated technical matter: “Yet Dr. Feist and his followers still claim that 15 [kwh per square meter] is valid equally in any climate and anywhere in the world. It is almost impossible in very cold climates as far as I can tell. I have not been able in all those last 12 years that I have been working with the German PHI to receive a good physics-based answer for this claim. Have come to the conclusion that there is none. The best explanation I can find is that 15 is the arbitrary result after applying the low load physics relationship between ventilation air and peak load in the central European climate.”

Until last year’s PHI-PHIUS divorce, Klingenberg publicly defended the logic behind the standard’s annual heating energy limit, so her recent challenge to the requirement is surprising, to say the least.

When Fauteux forwarded Klingenberg’s e-mail to me, he pointed out that her words are eerily similar to ones I wrote in my April 1, 2011 blog on this topic: “The next problem with the Passivhaus standard is that the annual space heating limit of 15 kWh/m²∙year is arbitrary. The requirement is easy to achieve in a mild climate, but tough to achieve in a cold climate. Where did this limit come from? It appears to simply represent the space heating energy required to heat a well-built superinsulated home in the climate of Central Europe, with the following assumptions:

  • Space heat must be delivered through ventilation ducts.
  • Ventilation rate = 0.3 to 0.4 air changes per hour.
  • Temperature of ducted air = no higher than 122°F.
  • The best windows in Europe are U-0.14 windows; the best achievable air tightness is 0.6 ach50.

With these limits specified, the best houses in a central European climate need 15 kWh per square meter per year for heating.”

Needless to say, I agree with Klingenberg on this issue. The Passivhaus standard's heating energy limit of 15 kWh/m²∙year is arbitrary.

Dr. Wolfgang Feist responds

On Feburary 7, 2012, Dr. Wolfgang Feist, the director of the Passivhaus Institut in Darmstadt, Germany, responded to questions about the Passivhaus certificate issued to the Rideau Residences.

Feist wrote, “The Passive House Institute has developed the Passive House Planning Package (PHPP) design tool to facilitate the design process and has instituted a rigorous (voluntary) certification process. ... The certifiers are entrusted with upholding the standard and ensuring the quality of the buildings they certify. They thus carry a great responsibility in their work and must diligently document the building as well as the quality of the components used. Should it become clear that an accredited Building Certifier is not up to this task, it is the Passive House Institute’s duty to revoke this Certifier’s rights to certify in the Institute’s name so as not to undermine either the Institute’s principles or the Passive House Standard itself.

“PHIUS’ assessment of the Ottawa house, unfortunately, was just such a case. In fact, much of the essential documentation necessary to determine energy balances — the foundation for the entire certification process — was not available when requested by PHI. Even on the basis of the partial data provided to PHI, it was clear that any properly conducted energy balance would result in an energy performance far removed from the Passive House Standard. PHIUS’ latest statements have shown that the organization is not even trying to claim that either the 15 kWh/m²a heating demand criterion or the 10 W/m² heating loadRate at which heat must be added to a space to maintain a desired temperature. See cooling load. criteria have been met. On the contrary, they claim that these criteria do not make sense. There is no question that an organisation taking this position did not take and, indeed, could not have taken its responsibilities as an accredited Building Certifier seriously and was acting to the detriment of the Standard. It is simply irresponsible to misguide the public by claiming that such changed criteria lead to the same proven results as the well-recognized Passive House Standard does. Those choosing to use different criteria should at least be so honest as to not use the term ‘Passive House.’ ”

Last week’s blog: “Service Cavities for Wiring and Plumbing.”

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Jan 27, 2012 1:08 PM ET

Canadian passive houses
by Don Fugler


This is a good report. I know many of the people involved and you treated them fairly. It would be interesting to know the status of the Montebello house mentioned: it seems to be waiting for certification according to reports in the Quebec press recently.

It is too bad that reputable builders who have created an energy-efficient house are getting entangled in technicalities. I suppose that this is the downside of certification procedures.

Jan 27, 2012 1:49 PM ET

by Keith Gustafson

Kind of sad when people working for the 'good' cannot get along

The proof is in the pudding as they say, one wonders after all the fuss an bluster, whether the building performs as a Passivehaus

Jan 27, 2012 2:14 PM ET

Edited Jan 27, 2012 2:17 PM ET.

Response to Don Fugler
by Martin Holladay

Thanks for your positive review of this report.

Anyone interested in more information on the Montebello passive house might want to read the September 2010 GBA news story that mentioned the house, Passive House Finds Friends in Canada.

Further information (in English and French) can be found here: Backgrounder: Passive House.

The images attached below came from

Montebello passive house.jpg Montebello passive house 2.jpg

Jan 27, 2012 2:28 PM ET

The road to hell
by Dan Kolbert

etc. Although I guess the quality of the intentions is up for debate. Long Live the Pretty Good House!

Jan 27, 2012 2:39 PM ET

About Dan's "pretty good house" comment
by Martin Holladay

Dan Kolbert and Michael Maines have been working on an article on the "Pretty Good House" -- a Maine proposal for a standard that differs in several ways (mostly by depending on something called common sense) from the Passivhaus standard.

Stay tuned -- GBA will be publishing Michael's article on the Pretty Good House very soon.

Jan 27, 2012 4:02 PM ET

by Lucas Durand - 7A

I'm looking forward to reading about the "Pretty good house".
I think I grasp the idea - I consider my own house that I'm building to be a "pretty good house".

I've often wondered why people sometimes get so hung up on arbitrary certification standards...
As though there needs to be a "brass ring" for people to be interested in building high quality enclosures...

Jan 27, 2012 6:53 PM ET

"Pretty Good House"
by kevin o'meara

I too am looking forward to this article. I do like the overarching goal that PassivHaus represents, and that certification could be desirable. Why? It represents much better and energy efficient housing than code or what most LEED projects achieve. Some day I hope that their could be many of such homes on this side of the pond and people will be buying them. These folks won't necessarily know all that goes into creating a PassiveHaus, just like I don't know all that is going on inside my computer, however these people know that they are buying ahighly energy efficient structure. Better yet would be if houses (at least new construction for a start) were to be required to have a sticker on them like any of our appliances do showing how much energy that house will use, however I remain a pessimistist that I will live long enough to see this be come required. I used the PHPP software to help design and build my house. It taught me much, however it certainly has some limitations in its use in North America, chiefly its required window data requrements that are not available (frame factors mostly).
I have read that to become Passive House certified all you need to do is acheive 0.6 ACH@50Pascals, and its 15 kwh per M2, which is not have to use their software. I certainly think their software can be reasonable accurate estimation, but why not allow (or better yet require) for objective measurement. The results could be used to refine the program over time.

Jan 27, 2012 9:06 PM ET

Response to Kevin O'Meara
by TJ Elder

You have a good point--if PH status could be based on actual energy use--something easily measured--then it wouldn't matter so much whether the brick ledger is accurately modeled. Results would be all that matter. A building could even have annual updates of its energy efficiency status, reflecting any modifications (e.g. adding a pool) and occupant behavior. Or, someone could build a "pretty good house" and later conclude that it meets PH efficiency, which may have less bragging rights but still make the owners happy.

Jan 28, 2012 2:39 AM ET

Compare the cost or certification to the cost of monitoring
by Michael Chandler

For about $2,000 I can get an eMonitor installed and watch the energy usage of my buildings as they are occupied and get immediate graphs representing system interaction with weather and client usage. I can see clearly how my reasonably well-built (HafassivHaus) homes are performing. The Bryant Residence ran through 57 KWh/sqM/yr during it's first twelve months and we have another that we have just finished a years worth of data collection and another where we are just getting started.

Monitoring looks like a very cost effective way to make continual improvements in your building systems compared to modelling. I'm not saying to throw out modelling but only that modelling without monitoring is only half the process and that a building that can be shown to use 15 KWh/sqM/yr should be viewed as equal to Passivhaus regardless of the pine tree not accounted in the modeling. I think that Ted Clifton's projects are more than meeting this mark.

Mine still have a ways to go but getting closer all the time thanks to all the great stuff I've learned from the community here and at the EVHA awards and NAHB Builder 20 and CGP-MCGP community.

Jan 28, 2012 3:12 AM ET

Edited Jan 28, 2012 3:15 AM ET.

Monitoring is "da bomb"!
by albert rooks

I look forward to the day when monitoring is accessible and dare I say... Common.

Modeling with the PHPP, or with anything else, steers the project to a good design. Site QA keeps the execution on track.

Monitoring provides what I think are the two significant benefits as stated above:

1: Check the model and see if it works.

2: It provides a continual feedback loop to the occupants. In the end, once these are modeled to very low, or no energy, it's down to the occupants and their use of DHW and plug loads.

What was the blog? "No net zero homes, just net zero families".

Passive House, Pretty Good House, LBC -All of these are great programs. As long as they don't get in their own way.

In the end, it's all about the buildings. Not the programs.

Jan 28, 2012 6:59 AM ET

Monitoring to see if a house meets Passivhaus?
by Martin Holladay

I'm all in favor of monitoring -- what we don't measure, we can't improve -- but the engineers and physicists who dreamed up Passivhaus have a false sense of precision. This amount of precision is unachievable.

In the real world, occupied Passivhaus buildings don't all use the amount of energy predicted by the model. If there are three Passivhaus homes, all identical, all modeled to use X amount of energy per year, one family will use X, one will used 2X, and one will use X/2.

The only way you can use monitoring to determine that a particular model of Passivhaus meets the standard is to build 1,000 of them, occupy them with 1,000 families, and divide the energy use of the 1,000 families by 1,000. And even then you have to normalize the data for weather!

Chasing rainbows...

Jan 28, 2012 7:35 AM ET

Dewey, Cheatum & Howe
by John Brooks

Michael Chandler (AKA ShelterNerd),
You are NOT authorized to use the term HafassivHaus
It is too similar to my trademarked terms "Half Passive House" and "Half Assive House"
I believe that Albert Rooks coined the terms "HalfassivHaus" and "HAHPP"
we will be contacting our attorneys

You MUST Cease and Desist...

Jan 28, 2012 8:03 AM ET

John, your language is not strong enough
by Martin Holladay

You're not supposed to say, "you must." The correct legal phrase is, "we demand."

Jan 28, 2012 10:01 AM ET

chasing rainbows?
by Paul Eldrenkamp


I don't think you're making a clear enough distinction between two evaluation methods in your post "Monitoring to see if a house meets Passivhaus?"

Evaluating a building by means of a PHPP model is a way of gauging the quality of the building as a a tool. I think this is a useful thing to try to do with some precision. Looking at actual energy usage of that building, on the other hand, is a way of gauging how well that tool is used. Two very different things, obviously. A really good building (that meets the PH standard, for instance) may have relatively bad actual-usage numbers because the occupants don't know how to use the building, or don't really care. A mediocre building can have really good numbers because the occupants are really aware and careful. This is not news to anyone who reads these discussions.

There's an ongoing debate about when to stop adding insulation and to start adding renewables. It seems like there could/should be a similar debate about when to stop spending money on the building envelope OR renewables and start investing in occupant training and feedback devices, as several people have suggested in this thread. I'm pretty sure some of my remodeling clients are achieving really good usage numbers just because they know we're looking at their utility bills with them periodically, and thinking about what the numbers mean -- that basic level of paying attention often saves more energy than adding yet another 1" of foam to the outside, and it's a lot cheaper.

--Paul Eldrenkamp

Jan 28, 2012 10:10 AM ET

Edited Jan 28, 2012 11:05 AM ET.

Response to Paul Eldrenkamp
by Martin Holladay

I understand that modeling and monitoring have different purposes. I was responding to T.J. Elder's suggestion that maybe "someone could build a 'pretty good house' and later conclude that it meets PH efficiency." To me, that sounded like an attempt to use monitoring to verify whether or not a house met the Passivhaus standard.

Let's say that there is a building -- perhaps the Rideau Residences -- that is the object of a dispute between two Passivhaus organizations. One group says that it meets the Passivhaus standard, and the other group says that it falls short. Do you think that you could resolve the dispute with monitoring alone?

I don't think so, because there are too many variables. The weather normalization alone is a nightmare -- it involves both heating degree days and insolation, as well as several other possible factors. Moreover, one also needs to monitor the thermostat setpoint, which may change daily. Appliances affect internal heat loads, so if the occupants buy a plasma TV halfway through the winter, the heat load that needs to be satisfied by the space heating equipment will be reduced. There are several other factors that could affect the monitoring data, including how the occupants operate their mechanical ventilation equipment.

With enough monitoring equipment and enough weather data, this may be achievable -- but I think that anyone who proposes using this method to determine whether a questionable house meets the Passivhaus standard will find the method daunting.

Jan 28, 2012 12:28 PM ET

Edited Jan 28, 2012 12:39 PM ET.

Upward spiraling costs
by albert rooks

I am also sensitive to the "Geewiz... We can do that now!? Lets add it in!!" issue.

Regardless of all the crazy material and system suppliers that keep foisting complexity and cost onto these buildings (me included)... The central message and effort for the Passive House Community is the continual focus on CEPH: Cost Efficient Passive House.

Sure there are big budget projects. What can you say? "A girls gotta eat" as the saying goes. However most of the people I interact with are continually working towards very high performance building for mainstream Americans.

That's the "Golden Target". Passive Houses for the masses. The whole point in the "endeavor" is environmental stewardship after all. The "masses" are where the volume and the need is.

I'm happy to share that we are hearing from a growing number of Habitat for Humanity chapters for PHPP's, air sealing questions and the like. Regardless of the fractures, Cost Efficient Passive House is growing at a really good rate in the US.

Add other programs growing at a good rate, and it's really good news for future mainstream Americans' ability to live in a "Low Energy & Resilient Home"

My point on monitoring occupant usage is not to say that we need to add more gadgets. The day I was looking forward to is the day when good monitoring of category usage (DHW, Heating/cooling, plug loads) are delivered by the utility. it doesn't look like it's out of reach if the country gets it's energy goals in focus. Simple metering, categorized and that is understandable to the occupants.

I think it's a service that should be delivered by the energy supplier; Not the project owner.

The modeling and building performance will not be an issue pretty soon. There are so many good tools and smart people using them. Once it's built, it's all up to the occupants behavior. I'm as bad as some of the worst of them. It was much worse when we had kids at home. There was, and still is no feedback loop to quantify and show you what your changes in behavior really do...

Jan 28, 2012 12:49 PM ET

Edited Jan 28, 2012 12:50 PM ET.

License's are available: HalfAssivHaus
by albert rooks

Micheal & John,

Have no worries about apparent infringement on my trademarked property: Halfassivehaus, half assive house, half-assive-house in all of it's various forms.

I'm a reasonable man. I'm willing to entertain granting a license for your use.

For a fee...

Jan 28, 2012 2:04 PM ET

A halfass, pretty good house built with common sense!
by Richard Patterman

I've always thought the Passivhaus Certification was just a ploy to sell overpriced German windows and HRV equipment. All good comments, but the basic disagreement is whether it is better to use very good locally sourced windows and equipment or "certified" windows and equipment from across the pond.

I quit following all the infighting when no one could justify the 15 kwh/sq meter, REGARDLESS of climate. Talk about half assed lack of common sense! One size does not fit all!

Jan 28, 2012 2:36 PM ET

Pretty good article
by Dan Kolbert

Martin has raised expectations - the Pretty Good House was the subject of our building science local discussion group (subject of blogs by both Martin & Michael Maines on GBA). I doubt we'll come up with a "proposal." As others have noted (and as Katrin seems to be belatedly owning up to), different climates have different needs. A shocking revelation!

Jan 28, 2012 3:10 PM ET

Edited Jan 28, 2012 3:17 PM ET.

Response to Dan Kolbert
by Martin Holladay

Once Michael Maines's article is published, I'm going to solicit guest blogs from volunteers who want to write about the "Pretty Good Texas House," the "Pretty Good Florida House," and the "Pretty Good Oregon House."

Uh oh ... I forgot to ask ... have you guys in Maine already registered for a trademark on "pretty good house" and "PGH"?

Jan 28, 2012 3:23 PM ET

by Dan Kolbert

Registered? Hell, most of us up here can't even read.

Jan 28, 2012 3:57 PM ET

Monitoring and bragging rights
by TJ Elder

Maybe it doesn't matter so much to compare houses normalized by weather data, or itemized by plug loads / appliances / internal gains, etc. If this is about joining the "energy miser" club and membership is based on utility bills, then bragging rights depend solely on that bottom line. For example, is it less meaningful to meet 4.75 kbtu/sf/a only with the thermostat to 63°F? If someone says, my household meets PH efficiency, would you say it doesn't count if they're always wearing a sweater (and maybe a hat)?

Jan 28, 2012 4:54 PM ET

I would say if a person stops
by aj builder, Upstate NY Zone 6a

I would say if a person stops buying energy.... BINGO.

Next problem. 9% property tax increases, and 9% healthcare cost increases. Dwarfs this green planet problemo financially at least.

$5,000+$15,000 now becomes $20k plus $60k= $80,000 annually in 2027. No 2% pay increases make a dent in these goofy numbers. Try to get a chunk of pre listing Facebook stock or grab some NG fract. land quick!

aj PGH AFS (armchair and field self-certified)

Jan 28, 2012 5:04 PM ET

Edited Jan 29, 2012 7:04 AM ET.

Response to TJ Elder
by Martin Holladay

You wrote, "If this is about joining the 'energy miser' club and membership is based on utility bills, then bragging rights depend solely on that bottom line."

I agree.

"If someone says, my household meets PH efficiency, would you say it doesn't count if they're always wearing a sweater (and maybe a hat)?"

Well, it depends. I think the PHPP software assumes 70 degrees F indoor temperatures or something close to it. So if someone has a Passivhaus and chooses to live at 60 degrees F during the winter and wear a sweater and a hat, then their energy use (all other things being equal, and normalized for weather) will be less than predicted by the modeling software.

Jan 28, 2012 11:18 PM ET

Arbitrary or not
by Philipp Gross

Even though the 15 kWh/(sqm yr) derived from some calcs for central European climate I have yet to see a non arbitrary counter suggestion. Nobody here argues that California needs less insulation than Minnesota and the PHPP "knows that" too. I don`t argue that a Half- passive house can be a good house but having the standard allows owners to define better what they want and have a 3rd party quality control. It is to bad of cause if the 3rd party does not agree internally :-). Also I believe that if owners who really know what they want, work with professionals who really know what they are doing the standard might not be the optimal choice because the optimal choice is probably unique for each project, even within the same climate zone. After all the Passive House standard brought some good discussions here, some of them seem to be never ending.... . I also hope to see more monitoring and published results. I don`t agree with "Chasing rainbows..." because luckily statistics are pretty well understood.

Jan 29, 2012 3:32 PM ET

Jan 29, 2012 4:34 PM ET

by Keith Gustafson

Pretty Interesting graphs

Things that strike me:

Actual house to house error goes up dramatically as efficiency goes up. Kind of a 'duh' but interesting. I would be hard pressed to put a foot of foam under my slab when forgetting to latch a window would cost me more.

Would love to see the year after year

would love to see which houses are using energy IOW they are blaming occupant behavior[quite probable] but perhaps other things are going on

The average German house is 10x passivhaus? I don't feel so bad

Jan 29, 2012 5:44 PM ET

by Philipp Gross


It is not surprising at all that the error goes up as efficiency goes up. The same energy goes out a open window in a efficient house and a not efficient house. Adding this "lost" energy to the total heating energy makes a much bigger difference (percentage wise) in the efficient house than in the inefficient one.

Sorry I don`t get the abbreviation IOW but most of it is most likely consumer behavior but some of it could be a overlooked thermal bridge etc..

The average German house includes the existing building stock. The difference is that the energy code for new construction and extensive remodeling is much stricter than here. Here you can still build a house that performs 10x worse than Passive House in Germany not. But you don`t have to feel bad anyway....

Jan 29, 2012 6:14 PM ET

What the graphs reveal
by Martin Holladay

As I said, monitoring data from one Passivhaus won't tell you whether or not the building meets the standard.

Jan 30, 2012 4:50 AM ET

Why 15kWh/m2a?
by Bronwyn Barry

Martin, Richard (and clearly a whole lot of PH folks),

The certification metric for Specific Space Heat Demand (or Cooling) has a firm basis in physics. It derives from the calculation of Energy Balance according to ISO 13790, and reflects the point at which it is reasonable and economical to offset the total heat losses of a building with free heat from internal and solar gains. The remaining Heat (or Cooling) Demand required was found to be around 15 kWh/m2a, hence the standard metric. Info on how this applies to other climates can be found here:

I must also clarify that your statement: 'Space heat must be delivered through ventilation ducts' is a common PH myth. The rare instances when the Heat Load may be low enough to where heating can be supplied through the ventilation ducting is on very small PH projects, and or in climates where winter days are typically overcast. This alternate to the SSHD certification metric can only be applied to residential projects as the intermittent usage of other building types will not allow for sufficient continuous internal gains to maintain thermal comfort.

It has been repeatedly shown that trying to heat PH buildings through the ventilation system is not typically a good idea. We are used to doing this with our conventional 'blast' furnaces, but when the air velocity and ACH requirements are reduced to the low levels needed in PH projects, delivering heat along with the air no longer becomes economical or effective. Smaller point source heaters do the job affordably and more effectively. There have been numerous papers presented at the PHI conferences documenting this and they're worth seeking out (ask someone in your local PH community to borrow their copy of the International Conference Proceedings for any of the last 4 or 5 years.)

Since the certification of windows issue was raised, there certainly is a discrepancy in how the PHI calculates their performance metrics for windows and how the NFRC calculates them. This is a simple protocol adoption issue. (See here: NFRC adopted the use of ASTM protocols, while the PHI uses EN ISO 10077-2 and EN673. Some manufacturers have found a simple work-around. ( PHI has been made aware of the 'lost in translation' window inputs for the American PH market. I'm in dialog with folks on all sides and am hopeful an official solution can be found. However, it won't be ready any time soon!

In the meanwhile, interest and knowledge in the PH concept continues to grow here in the US, despite the recent 'kerfuffles' on all sides. Like Albert, I'm seeing practitioners using the PHPP as the design tool it was intended to be. Projects are 'dialing in' their assemblies and getting creative with 'boxy.' Design is really where the real opportunities to optimize lie, and architects who learn to control the levers of performance will have the most success with PH. Projects where performance is front-loaded into the design, and not added as an afterthought will also be cheaper and easier for contractors to build. Design Build will ultimately be the most successful of all the project delivery methods.

The PH community in the US still has a way to go before we fully grasp the complexity that the PH standard offers and requires of us. The projects built here so far are all admirable in their attempts to achieve the certification standard, whether they actually made it or not. There will be building failures, and indeed there are already a few projects experiencing overheating problems due to lack of understanding of the shading and cooling parts of the PHPP. However, I'm betting those failures will be fixable (and fixed) because the people I've met in the PH community across the globe are all passionate about quality - or they would never bother to attempt a PH level project. PH projects are also driving the local market to get serious about performance. New products are being introduced rapidly. (Serious Windows has an advertisement that states 'No need to buy German!') Imports will slow down when the local market provides reasonable equivalents, but right now the import market in the PH world is booming. It ultimately won't matter whether people have their buildings 'certified' or not and Dr. Feist himself has stated that he doesn't care - as long as they are modelled and built properly. The PH community is shifting the focus of the building industry to quality, which will not only improve performance, but will also last longer. Now isn't that Phundamentally what every man (and woman) wants?!

Jan 30, 2012 5:24 AM ET

Edited Jan 30, 2012 4:45 PM ET.

Response to Bronwyn Barry
by Martin Holladay

Thanks for you long and informative post.

You wrote, "The certification metric for Specific Space Heat Demand (or Cooling) has a firm basis in physics. It ... reflects the point at which it is reasonable and economical to offset the total heat losses of a building with free heat from internal and solar gains."

As stated, this is an economic assessment, not one based on physics. Many U.S. builders disagree with your assessment that 15 kwh/m2 is "reaonsable and economical." It is easy to choose actual Passivhaus projects where it's hard to see why it is "reasonable and economical" to spend an additional $10,000 for insulation (or Siga tape) to achieve an additional $100 per year in fuel savings. Your definition is circular; it has nothing to do with physics.

You wrote, "It has been repeatedly shown that trying to heat PH buildings through the ventilation system is not typically a good idea." Then why is the definition of Passivhaus at the very top of the Passipedia web page -- a site I was directed to by Dr. Feist himself, who recommended it as an authoritative resource -- still misleading people? That definition states, "A Passive House is a building, for which thermal comfort (ISO 7730) can be achieved solely by post-heating or post-cooling of the fresh air mass [ventilation air] which is required to achieve sufficient indoor air quality conditions – without the need for additional recirculation of air.”

You wrote, "indeed there are already a few projects experiencing overheating problems." Those of us who designed and built passive solar houses in the 1970s can see at a glance that this will be a problem with many Passivhaus designs. But we are basing our judgment on experience, not the PHPP.

Jan 30, 2012 12:11 PM ET

PH and overheating
by Doug McEvers

I was in the Smith House in November for the 2nd Annual Passive House conference, home tour. The day was sunny, outdoor temp about 30 and it was warm in the house, over 80F I would guess. This home has a lot of south facing glass (high and low) and the direct beam goes way back into the house. The house was filled with a whole bunch of energy enthusiasts (at least 40) so I am sure this raised the indoor temperature a bit (Martin can do the human Btu calc, they probably all had a lot of hot coffee that morning).

The Smith house would and maybe has benefited with a better trellise/pergola on the lower bank of south facing windows and some additional interior thermal mass. A bit of overheating in the winter in a cold climate is not the worst thing, kind of feels good in January when the outdoor temp is -30.

I take my hat off to the Passive House folks, they are in large part responsible for the advanced discussion we are having today here at GBA and elsewhere.

Jan 30, 2012 3:50 PM ET

Circular thinking
by Bronwyn Barry

Hi Martin,

You're right about the circular thinking in my explanation of the SSHD number. I've reached out to some people who are smarter than I am to help clarify.
Regarding the issue of heating though the ventilation supply: the definition of PH does not state the fresh air must be heated (or cooled) exclusively in the ventilation ducts. It just needs to be heated at some 'post' supply point. Whether that occurs partially within the ventilation system (and some climates require this) or totally outside the ventilation system is up to the mechanical systems designer. The main point is that the air in a PH only needs to be heated once, because the overall energy loss is so massively reduced by the efficient building envelope. The interior air does not need to be heated, and then re-circulated and re-heated multiple times such as occurs with a typical furnace 'ventilation' system. Is that a little clearer - at least on that subject?!

Jan 30, 2012 4:10 PM ET

Edited Jan 31, 2012 9:56 AM ET.

Response to Bronwyn Barry
by Martin Holladay

This is just another red herring, I'm afraid. The air in a Passivhaus only needs to be heated once? How do you make sure that happens?

Let's say a Passivhaus designer chooses to install an electric resistance baseboard heater -- or wall-mounted electric heaters like I saw in Dan Whitmore's Passivhaus in Seattle. Is each molecule of nitrogen and oxygen somehow given a tag, and told that they only get to approach the electric resistance baseboard heater once? And if the same molecule drifts too close after being heated once, what type of Passivhaus contraption prevents that molecule of oxygen or nitrogen from being reheated?

Whenever you have a heat source in a home, there is a strong likelihood that some of the gaseous molecules of air will get heated more than once. And so what if they do?

Jan 30, 2012 9:32 PM ET

Edited Jan 30, 2012 9:34 PM ET.

I want to play red herring too!
by Linda Whaley

Naturally there will be air molecules being recirculated and possibly heated more than once (especially if you are fortunate enough to live in a "Passion House"!) Of course there may also be more mundane re-heating of air molecules, but not to worry - we'll get the PH-olice on the case!

PH Recirc Air.jpg

Jan 30, 2012 10:34 PM ET

PHIUS Conference 2011 Rideau House Presentation
by Jesse Thompson

For those actually interested in the specific project at hand, Ryan Abendroth from PHIUS made a really thorough and interesting presentation on the Rideau House and the events that surrounded its certification and the back-checking that went on after the complaint about its certification. He talked a lot about the shading issues that only became clear after the complaint was filed, as well as the thermal bridging issues that resulted from poor detailing. Here is a link to his presentation, no words, but lots of interesting graphics and photos:,...

The other presentations from the PHIUS 2011 Conference are at this link, there's lots of good things there:

Jan 31, 2012 1:25 AM ET

The Real Story
by Lyndon Than

The behaviour of people in this article is the real story. I have always been impressed by the elegance and comprehensiveness of the Passive House concept and the PHPP - and consequently by the people who offerred this system to the world. Sadly, I guessed from the first news last August about PHI and PHIUS's split that the the issue had to do with the challenge of the Rideau House Project. I find it amazing that PHI could be so erroneously and negatively influenced by one person's challenge of one project - Perhaps there have been other issues coming to a boil - but still - throwing away PHIUS based on what seems such a cursory review of evidence - of issues which turned out in the end to be of miniscule proportions IE the PHI-PHIUS bond was broken over perhaps half a kWh/m2a - on one project. I can only conclude (and with much compassion) that there is something significantly dysfunctional at PHI.

Jan 31, 2012 2:58 AM ET

Lyndon, One could make a
by mike eliason

One could make a similar conclusion based on the actions of PHIUS over the last year, that it's not the PHI that is significantly dysfunctional...

In the end, it's probably a combination of both that led to where things are, though.

Jan 31, 2012 6:29 AM ET

Edited Jan 31, 2012 6:34 AM ET.

Ryan Abendroth's presentation and finger-pointing
by Martin Holladay

Thanks for the link to Ryan Abendroth's presentation. One possible conclusion: all of the various PHPP iterations of this disputed building are relatively close, in the grand scheme of things, and the number of BTUs that these organizations are fighting about is relatively small.

Concerning finger-pointing: we have two organizations. They are both pointing across the Atlantic Ocean, shouting, "They done me wrong!"

Sadly, I see plenty of evidence that both organizations are accurate in their complaints.

Jan 31, 2012 11:17 AM ET

Certification & success
by Jesse Thompson

Ryan was very candid during his presentation. I may have mis-heard, but my memory of the narrative was that the project was not designed from the beginning to be a Passivhaus, but the project goals were instead to be a very low-energy building constructed with only North American building components. It was implied that Passivhaus came late to the design, and that there were many details that would have been built differently if Passivhaus had been the goal from the beginning.

As well, my impression is that issues like this have been one of the major reasons why PHIUS has developed their PHIUS+ Certification (, which, unlike PHI in Europe, involves site inspection of projects before Certification, because PHIUS is so nervous about "bad" projects leading to controversies like this one.

Personally, I don't think this project is a failure at all, but instead is a tremendous building caught up in a turf battle between Certification entities, because as you said Martin, we're dancing on the head of a pin with the differences between the range of modeled energy use, let alone actual energy use.

As well, the 20,000 built Passivhaus in Austria seem to follow the model of this project as well, get building quickly and don't worry so much about precise certification of every single building, too much attention to detailed certification only gets in the way of ramping up the construction of low-energy buildings as fast as we desperately need right now. Since I'm not a Certification entity, I will always bias towards more projects built close to a target, rather than all or nothing. But I can understand why a Certification entity would have to see things differently.

Jan 31, 2012 9:28 PM ET

$10,000 for 100$/YR?
by Philipp Gross

Martin, you where throwing some numbers at us earlier I was wondering if they were an educated guess or based on project estimations? I doubt them a little because they do not correspond very well with what I usually see. So if we`d take a approx. 2000 SF house heated with natural gas (5 Cents/kWh now but who knows the prices down the road) you are estimating that it costs $10,000 to bring the project from 25 kWh(/m^2YR) to Passive House !? I think that bringing the project down to 25 kWh(/m^2YR) is already such a huge step compared to normal construction that all it takes for passive house (15 kWh(/m^2YR)) is smart design, detailing and maybe a couple bucks for more cellulose! Nevertheless I am OK with 25 kWh(/m^2YR), if you make that a standard I might be using it :-). How about a standard where the roof area has to be big enough to potentially offset the operational energy?

Feb 1, 2012 5:38 AM ET

Response to Philipp Gross
by Martin Holladay

First, I want to admit that I was pulling numbers out of the air to make a point. (I was thinking of a Passivhaus built last year in Lancaster, N.H. by Ben Southworth. According to Ben's PHPP calculations, that house required an R-78 floor — he ended up using 12 inches of polyiso — and an R-148 ceiling.)

Here's another real case: Marc Rosenbaum was running the numbers on Claudia King's house in Maine. They started out with 4 inches of polyiso on the exterior of the wall sheathing (with more insulation between the studs), but the house still fell short of Passivhaus. The team calculated that bumping up the exterior polyiso from 4 inches to 6 inches would cost at least $2,880 -- probably more. They decided not to do it, however, because the extra foam would only save 950 BTU/sf/year. I forget the size of the home, but if the home measures 2,500 square feet, that's 2,375,000 BTU per year, which you could supply with a ductless minisplit for about $41 per year

I'll admit that the Claudia King example shows I was exaggerating when I referred to spending $10,000 to save $100 a year. It would have been more accurate to talk about spending $2,880 to save $41 per year. But you get the point.

Feb 1, 2012 3:13 PM ET

Edited Feb 1, 2012 3:44 PM ET.

15 is dead. Long live 15.
by Katrin Klingenberg

Thank you Martin, for a very good article. The Rideau residence is in certification range, I think that much is clear (thanks Jesse for referencing Ryan's presentation above). If in doubt they might just have to kill the one coniferous tree and turn it into biofuels... :)

I think it is an awesome project and I congratulate the Team Straka to have built this first certified project in Canada in a very difficult climate and best of all using all North American materials and components!!! They have shown that it really is true, you don't have to use expensive European imported goods to get there. This project will help hugely to make the case to the government that Passive House is a valid option for Canada. Well done and keep on building!

The discussion about the reason behind 15 is a nice segue way into my brand new Klingenblog that is launching today, with more discussion on this topic. The title: 15 kWh is Dead. Long Live 15 kWh.

Should be fun, to read more go here:

Feb 1, 2012 4:12 PM ET

Response to Katrin
by Martin Holladay

Thanks for your kind words, and congratulations on your new blog and your bold proposal.

I look forward to reactions from readers.

Feb 1, 2012 9:33 PM ET

So what
by Ed Dunn

I, for 20 years, have promoted sustainable building in Northern Arizona and the Flagstaff area. I have designed over 45 passive solar sustainable homes and I have built 30. When I read about the Passivhouse requirements a few years ago, I was pleased to see that the method followed the accepted principles of passive solar design; tight, well insulated, oriented to sun, glass, mass, and ventilation.

When Coconino County and the City of Flagstaff formed the Coconino County Sustainable Building Program about 8 or 9 years ago, I helped develop the checklist for building a sustainable home. It exceeded LEED as it promoted the idea of passive solar. LEED for residential eventually came around to the idea, but not very much. It was also noted that LEED promoted larger houses to get the max points and LEED homes did not seem to perform as well, even though they might be platinum. I suspect the same could happen with PH certification, if folks are not careful. It becomes a game of chasing points rather than achieving true sustainability. Smaller, simpler homes do this.

I would not be so concerned about the certification, rather, use the checklists as guidelines for designing and building. It's not the points, it's the performance that counts. I actually have high performing homes that are not certified at all. The occupants are very happy with near zero energy bills, the great comfort and the knowledge that they know how much carbon was emitted in the building of their home. Certification is often used as a selling point for a home, but most all of my clients are in their homes for the rest of their lives so this is not a concern.

Feb 1, 2012 10:56 PM ET

It's easy, it's not easy
by Andy Kosick

15 Kwh/m2 is easily achieved anywhere, you just start turning down the thermostat... I'm just saying:)

But seriously, a little perspective from the trenches of the vast majority of our housing stock. I like standards as bench marks but as an energy retrofit contractor who generally works for people with modest incomes (that would be most people who live in existing houses) this infighting at PHI is depressing me. Spitting hairs on a house that's more efficient than almost anything I'll ever work on isn't very inspirational. I work very hard to get anywhere close to a pretty good house.

I for modeling as a guide and monitoring as a certification. That gets the occupants in on it and they're often the biggest part of the equation.

Feb 1, 2012 11:15 PM ET

Response to Ed
by TJ Elder

The beauty of PH is that it's not about chasing points. With LEED-H you have 138 possible points, and just 90 needed for Platinum. Start with a small home and get a 10-point head start. It's certainly possible to hit Platinum even with code minimum insulation, because there are so many ways to score points. I think this reflects a strategy by the USGBC to expand market share by letting people find ways to get good scores, rather than being too rigid and exclusive. PH isn't like that--you really have to follow the recommended strategies to meet the standard. Any project that does meet the PH standard will certainly be exceptional, at least in the context of houses in the US, which generally have a low standard of energy efficiency.

Feb 1, 2012 11:30 PM ET

Turning down the thermostat
by TJ Elder

Andy, that's what I keep saying, but really not kidding. This is a real challenge for people, to say there is not a hard and fast relationship between efficiency and energy use. Say for example that I admitted to not owning a fuel efficient vehicle. Your reaction might be that I must use a great deal of gasoline, because obviously as an American citizen, an adult and living in the modern world, I must spend 12-15 hours a week behind the wheel of a large automobile. However this is not the case. Likewise, in my view it is not a certainty that inhabiting a home with lousy insulation necessitates using a huge amount of natural gas. There is another variable, if we dare to admit. What I keep thinking is how new this idea is, that no matter how cold it may be outside you must be able to maintain 70°F inside your abode. Did Queen Victoria live this way? What about the first 30 Presidents of the US? But these people must have been from a step back on that chart of human evolution, with a lot of body fur, like a wooly mammoth?

Feb 2, 2012 8:42 AM ET

Response to TJ Elder
by Martin Holladay

Q. "What I keep thinking is how new this idea is, that no matter how cold it may be outside you must be able to maintain 70°F inside your abode. Did Queen Victoria live this way?"

A. "Poor Queen Victoria found Buckingham Palace so cold that she used to take brisk walks along the great corridor to stay warm." (Source:

So, you're right: Queen Victoria did not live that way. But if you are implying that the Queen was quite happy with the situation, you are wrong. As she would have put it, "We are not comfortable."

Feb 2, 2012 9:21 AM ET

by Alec Shalinsky

Hello. I am in the process of building a GOLD CasaClima house in Italy. Although it will NOT be certified PHI, it will meet most if not all of the standards (ie, less that 10KWH/m2 energy and ACH of 0.6). What I find interesting is that there is something similar happening here in Italy. The founder and Ideologist of CasaClima, Norbert Lanschtner has come to a disagreement with the board of the agency he founded. From what we understand there is a difference of opinion on how the agency should evolve and what its boundaries should be.
This is very sad. Norbert has committed 10 years of his time to the advocacy of Energy Efficiency and bringing the need for efficiency to everyone's attention. What is disturbing is that like PHI, CasaClima should concentrate promoting the idea and not get involved with politics or marketing. So, if PHI has their noses out of joint because a Canadian product (I'll probably be shot for this!) is as good as a German product, then guess what, so be it. My evaluation of the choice of a product is based on many things. The performance of the product, the local availability (transportation=energy use) and the cost.
I am a firm believer that if you want to make energy efficient home "mainstream" then they MUST be available to everyone, not just who "can afford it". I've had the argument before. Why should I pay double for a dishwasher that uses less water. It should be other way around to motivate people to buy energy efficient products. The house possibly won't cost less, but it certainly shouldn't cost more, hence the evaluation of product choice.
Anyway, very valid points in the article. Pity something good gets all messed up with someone proclaiming that "mine is longer than yours!"


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