One of These Passive Houses Is Not Like the Other

A Passive House Institute U.S. supporter argues that PHIUS rules far exceed the requirements of the international Passive House Institute.

Dear Editor,

I am writing to express some concerns regarding your recent article “The Two Passive Houses: A Comparison.” For disclosure, I am a current member of the Passive House Institute U.S. (PHIUS) Technical Committee and a PHIUS instructor for onsite QA/QC professionals. Despite being more directly familiar with and professionally related to PHIUS, I try to stay neutral on the political nature of the Passive House Institute (PHI) vs. PHIUS debate. However, I feel that your article is flawed in many ways, and I wish to express some constructive feedback.
First of all, the article begins by rehashing politics of the original split of PHIUS from PHI from a decade ago, and it is written in a manner that would seem to guide readers to believe that PHIUS did something unprofessional to cause the split. While these events pre-date my experience with the passive building community, it is clear that the circumstances surrounding whatever event happened with a brick ledge in Canada 10+ years ago are disputed. In an article in 2019, is this really so relevant so as to lead the conversation?  Frankly, while it is perhaps an interesting anecdote about the original split, it is not particularly relevant to comparing the organizations today.
In fact, the only real relevance to focusing on this aspect of the original split between the organizations is that PHIUS has doubled down on an extremely rigorous, third-party quality-assurance verification process for which PHI does not have a required equivalent. The requirement that all PHIUS+ projects must meet the mandatory criteria of EPA Energy Star Certified Homes, EPA Indoor airPLUS, and DOE Zero Energy Ready Homes, in addition to the Passive House-specific energy criteria—along with the requirement for this criteria to be independently verified by trained onsite verification practitioners—is an extremely relevant and critical aspect of the comparison between the two certification schemes. It’s notable that your article includes only a mere paragraph on the topic of quality assurance, and makes no clear observation that PHI is largely a consultant-driven program with no mandatory third-party on-site verification protocols, and no requirement to harmonize with other relevant national building science certification programs.
Additionally, your coverage of the distinction on the certification criteria is cursory at best. PHIUS—again—has taken the high road in terms of rationalizing its program with national realities of energy costs, construction costs, extremely diverse climate regions, etc. All of this has resulted in a more robust and diverse, appropriate certification program based on DOE Building America-sponsored, Building Science Corporation-collaborated Climate-Specific Passive Building Standards. This is an actual science- and economics-based approach to achieving exceptional performance in the various regions of North America. Your article doesn’t even mention that this research exists! How can you portray this article as being a reasonable overview of the two programs while failing to acknowledge this critical milestone in the PHIUS+ certification process? Simply saying that PHI “deals with it differently” isn’t reasonable…. The reality is that they seem to deal with it on an ad hoc, arbitrary basis where it suits their interests to acknowledge that, yes, 75% of the United States has cooling loads and humidity unlike central Europe, and if they want certified projects in other regions they have to make exceptions. This is a technical flaw in their approach as I see it, and your article glosses over it like it is acceptable and of little consequence.
The article is rife with anecdotes about practitioner perception of the programs that are conveniently located in the geographic areas where PHI’s Central European climate more or less overlap with North America’s (Northwest and Northeast). Outside of these two geographic realms, it is entirely accurate to say that the passive projects being certified are mostly all PHIUS+, and the comps aren’t even close. Why is there a lack of representation of practitioners in areas like Chicago, Kansas City, Minnesota, Alaska, etc? I’m sure you’d find different commentary had you chosen a more representational source for your interviews.
Overall, in order for Building Green to remain a relevant trade publication, it needs to devote itself to a degree of objectivity and journalistic rigor that engages and informs professionals. This article was written in a manner in which it seems the author already had an intent of how they wanted to portray the distinctions of the organizations irrespective of the facts and realities of the situation. Anyone who cared to take a professional eye and truly understanding the practical distinctions between the two programs would get very little out of this article. I recommend for this reason that you withdraw this article until you can find the time to do better professional journalistic due diligence.

Chris McTaggart, Co-Owner, Building Efficiency Resources (BER)


Editors’ response:

Thank you for writing. In no way did we intend for the opening sentence, about the history of the split between the two organizations, to imply that PHIUS did something wrong. I’m sorry if it read to you that way. We appreciate the additional details you’ve provided here on our admittedly cursory coverage of the quality assurance and standards development differences between PHIUS and PHI. We’re grateful for your input, and for the comments provided on the article by others.


Published August 19, 2019

McTaggart, C. (2019, August 19). One of These Passive Houses Is Not Like the Other. Retrieved from https://www.buildinggreen.com/op-ed/one-these-passive-houses-not-other

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August 19, 2019 - 8:06 pm

PHIUS moves the goalposts, by lowering the bar, and then argues the increase in compliance testing is more rigorous than PHI and is somehow better..Why don’t you change your brand if it is so superior? In the future when buildings are all electrified certification/ compliance/home auditing will be a dying industry. You will simply look at one energy bill and see if you hit the targets. A competent CPHD can model building performance in PHPP or Wufi Passive with very predictable results, couple that with blower door success and inspection testing is not necessary, rendering the plaque a bit of overpriced bling. Being a high achiever; PHIUS being plan B, I’ll stay with plan A. Please change the name, and end the defensive stance.

August 19, 2019 - 8:25 pm

I have direct experience with building a Passive House in the Chicago suburbs; Palatine, Illinois to be specific.

We tried the "expert" route, using PHIUS certified professionals from Evolutionary Home Builders, including Brandon Weiss, Eric Barton, and Patrick Danaher. We ended up bitterly disappointed, losing $30,000 of our life savings and over a year of our time. We ended up successfully completing our build, but only after moving forward on our own as the general contractor.

When we reached out to PHIUS, Mark Miller and Katrin Klingenberg specifically, for help, they made it crystal clear what their priorities are.

The details are available on our blog documenting our build: www.kimchiandkraut.net

Whether the PHIUS+ certification protocols represent a "dumbing down" of the original Passive House concept is debatable, and those smarter than me have pointed out some flaws: https://foursevenfive.com/blog/bsc-phius-passive-building-report-not-air...

As a homeowner who has experienced the worst of what the construction industry can dish out, it's hard not to be cynical about all of the "green" building certification programs. In the case of PHIUS specifically, my question is what, if anything, are certified PHIUS members prepared to do to ensure that no other homeowner has to go through what my family and I have endured?

I hope that certified PHIUS members will practice the "degree of objectivity" that Mr. McTaggart expects from Building Green when it comes to enforcing some kind of ethical standards for their own members. If, however, PHIUS members refuse to police their own, then who will?

August 20, 2019 - 4:19 pm

Issues aside, thanks for doing the right thing by giving Chris McTaggart an opportunity to comment.

Paul Grahovac


September 3, 2019 - 2:28 pm


Your commitment and passion to build better is laudable. PHIUS has offered comparisons to the two standards for three specific buildings. They clearly show PHI's targets are harder than those set by PHIUS for the same climates. You can download that presentation here: http://nesea.org/session/multifamily-passive-buildings-evaluation-measured-performance. Either way, our SHARED planet doesn't really care which one of the 'passive building standards' design teams use. It just cares what they deliver. Please go forth and DELIVER!

Yours in solidarity with GREAT performance outcomes,