“The Passive House is not a brand, it is a building concept which is open to all.” – Anton Kraler
I have to say, I completely agree with Kraler. I don’t view Passive House as a brand, but a concept that belongs to the greater built environment (Passivhaus is a greater good!). And as a concept, I find it very sound and worthwhile. So it was interesting to be forwarded the inaugural blog post from the PHIUS blog, Klingenblog (I’m not making that up!).
Yes, PHIUS has jumped on the PHlog (Passivhaus+Blog) bandwagon, and the first post seems a prelude to opening Pandora’s box and watering down the standard. Fresh off being criticized for merely questioning the implications of banning certain products that would influence maybe 2 or 3 projects/year, I find this line of thinking to be in the same vein.
Should the standard be relaxed for buildings in extreme environments?
Katrin calls for letting go “of the illusion that there is a God-given magical number that can cost-effectively be adhered” (the 15kWh/m2a) – that the cost of “meeting the mark” in certain climates is both problematic and costly. This is due to the “difficulty” (perceived and real) of achieving Passivhaus in extreme environments (especially for single-family houses or small buildings). We don’t view this as a flaw – in fact, this is the inherent aspect of Passivhaus that makes the most sense to us, plus our belief that there are no small-house penalties, only bad design ones. Call us purists, we honestly don’t mind!
Relaxing the standard in extreme climates also seems to give blessing to maintaining the status quo instead of addressing the structural problems of said extremes. Maybe any single-family home, Passivhaeuser included, in isolated, Ã¼ber-cold climates can’t truly ever be sustainable. Indeed, maybe in extreme environments, buildings should cluster together for warmth and affordability (across a number of scales).
Drawing conclusions from only 100 buildings
Regarding process, Kat writes, “PHIUS is proposing to the PHIUS Tech Committee — composed of industry and policy leaders from the United States and Canada — to leverage the PHIUS dataset of 100 buildings, and to solicit feedback from the consultant community to create a new protocol that will allow Passive House professionals to determine practical modifiers to the standard to address climate, small home and retrofit scenarios.” I see two parts to this – first, it’s good to see there will be oversight on something like this, and second (and probably even more important), consultant buy-in/feedback. EnerPHit seems to address the PH retrofit question rather well. It’ll be interesting to follow this process.
There also seems to be an inherent liability in utilizing the first 100 projects (buildings?!?) given that a number of these were probably shoehorned. Plus, after building the first – the process is streamlined and optimized – there is a significant learning curve! Finally, and perhaps this is jumping the shark, but revisiting the standard with a very non-representational sampling seems premature, and would potentially be better served at 500 buildings or when more consultants have built and/or certified several projects.
On some level, I see relaxing the standard as an “out” for product manufacturers needing to developing better performing products or getting consultants/designers to work hard to really optimize their projects. It also doesn’t force folks to deal with the hard philosophical questions that may be worth asking.
Looking hard at where we live
If PHIUS is going to claim consultants should be auditing embodied energy/carbon in projects (which we completely agree with) – then maybe we should also be taking a really hard look at how and where we live. After all, food and transportation can significantly affect one’s overall CO2 footprint – especially in extreme locales, and especially in low-energy homes.
So are we unbending purists? Nattering nabobs of negativity? I’d like to think we’re just asking the difficult questions that deserve some face time. What do you think?
Mike Eliason is a designer at Brute Force Collaborative in Seattle, Washington.
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I do not follow the daily happenings at PHIUS but I do strongly support Passive House and the goal of building very low energy homes. If the current PH standards are unworkable in very extreme North American climates some type of climate zone differential is in order. We still want people living in extreme climates to consider building very energy efficient homes even if it does not quite meet the original PH requirements.
For my building area, the
For my building area, the Adirondacks, PGH as presented so far is perfect. Simple, open standard. Actually it is what we should have, it is a reference. We all should be building from a reference, not a mandatory standard.
Thanks for posting this blog entry here. I know you have a blog at brute force collaborative also - but posting the entry here aswell, is nice, so that a guy like me can benefit from reading up, about the latest news in PH in north America.
There is one difficulty, which exists within the architectural profession, and it has less to do with standards, or low energy, or anything to do with green. You could take the most unhealthy, un-green, massive, commercial, speculative monstrosity constructed by an architect, anywhere in the world today - and the exact same difficulty will apply there - as we tend to find in the green architecture area also.
Take this quotation from the blog entry,
It is only a minor detail, in the wording of a sentence, but it is something that we need to be wary of in the world of construction client consultation - whose project is it? Too often, in my lifetime, I see people working in a variety of the construction professions, who are extraordinarily talented and dedicated. They really mean well, and want only the best for their clients.
Unfortunately however, competition exists in every marketplace, in every profession, in every field. Even the whole 'surge' of interest amongst construction professionals in the last few years, has more to do with a competitive strategy, and less to do with 'green' itself. As the recession hits all parts of the world, there is a rush to create what management consultants would term 'differentiation'. How to stand out, and distinguish oneself from the crowd.
Unfortunately, it happens, that in the heat of competition and differentiation - construction professionals begin to get too relaxed in the vocabulary that they use, when they talk about projects - and they speak about projects, as if they owned them. Construction professionals can forget, that we do not own projects ever. They belong to someone else, who has a vision in their own mind, of what they want. It is the employers of construction professionals who build projects, rather than the professionals themselves.
Maybe, it is a good idea, from time to time, to remind ourselves, that our involvement with a project is so short in the context of the total lifespan of something such as a building. It is a good enough bet too, that the building that we leave the employer with, at the end of this short process, will be modified, changed and altered over its lifetime. It is a good bet also, that the use of that same building will alter significantly. People will occupy homes, and buildings, differently twenty years from now, than how they do today.
Maybe we should ask ourselves, over the lifespan of a building - say 60 years for arguments sake - what does that difference between 15kWh/m2a, and 16kWh/m2a, actually mean? Hand on one's heart, and truthfully, I wonder how many construction professionals today, who walk past projects that they designed twenty years ago, can summon even the slightest interest in those same projects today? I mean, if the construction professional who designed a project, cannot get too bothered, twenty years from now, why should anyone else?
The truth is, that when we as construction professionals think about the project we completed yesterday, we think of it as new born perfection. When we see a project, we designed twenty years ago, or even ten years ago, it is like cringe! You see all of the amateur mistakes. You see the distance you may have travelled since then. Projects from a decade or more ago, do not really interest us. That is not right either. There is something wrong with that. But that is another story.
The problem with trying to meet the German born standard in climate 6 and 7 is the proportion of solar energy needed to meet heat demand. In milder climates the heat loss/ heat gain ratio through the windows annually is around 1:1. To meet PH in colder climates a heat loss/ heat gain ratio can go up to 1:3 even with a super insulated package. Day night temperature fluctuations can be a consequence. Discomfort usually leads to occupants monkeying with settings, adding new mechanicals and could result in energy use not included in the exercise of energy modeling the design.
The problem with the concept of PH is its universal posture. The strength of the PH concept is as a marketing package - simple, straightforward, within the attention span of contemporary minds.
I hope to continue to see regional groups band together, collaborate and refine the best solutions for themselves and their neighbors.
The biggest problem I see with the calling PH a 'universal posture' - is that it is conceptually, but not in built reality. If you take the exact same house, what is needed to achieve PH in San Diego (near code minimum and lots of shade) won't fly in Salt Lake. What works in Denver significantly under performs in Seattle. What works in Duluth is complete overkill for NYC.
Yes, the straightforward-ness, the simplicity are a draw for many. But the reality is all this posturing of late is over one typology - single family houses - in difficult climates. Before we change the definition, let's at least get our semantics in order.
A number of the projects we're aware of locally have either been self-designed, self-built or self-developed - so the PHPP'er was heavily invested in the project. But I completely understand your point and tend to agree. There are a number of people that care about how their buildings age and perform, if their clients are satisfied, if used as owner desired... These are the folks who maybe tend to use 'our project' rather than 'your project'.
Also, the difference between 1kWh/m2a could be as much as $300/yr on a 2400 sf house before rate increases. It could also be well under if the inhabitants are cozy at 65 or 66 instead of 68.
My opinion on Passive House
My opinion on Passive House as a building concept
I agree that it is! And if you use it as such it actually doesn't matter too much if it comes in @ 17 kWh/m ² YR and 0.8 Ach₅₀. But if you want to certify it the line has to be drawn somewhere for simplicity. The biggest plus of certification is in my opinion for the client, who gets a third party quality control. Yes, the 15 kWh/m ² YR is also a sweet spot for Central Europe, when cut the mechanical system costs tremendously. This however does not work in most other climates and/or building cultures because it gets too cold and/or standard mechanical systems are darn cheap. So does it make sense to change the numbers? In my opinion only if there is a very good argument that I have not seen so far. And the argument that some Passive Houses have R-70 Slabs and "only" R-40 walls does not count since this is up to the designer and maybe he had a good reason.
My opinion on "drawing conclusions from only 100 buildings
No certainly not! Maybe 100 buildings in each climate monitored over the course of at least 5 years. And this work would best be done by Universities with several Master and PHD theses.
So what needs to be done
The PHPP standard values (which most of them can be changed manually) have to be figured out for the US culture to get more accurate results on plug loads, lights, hot water etc. Also the primary energy factor should be adjusted for the specific regions. This should be fairly easy and really should have been done much earlier.
The PHPP should be checked for climate specific details where the software might does some simplifications (cooling/ dehumidification/thermal mass, etc.). This work would be much easier with the people who actually developed the software (which I think is great by the way). This is a long learning period and measured data might helps. Get the academics on it… Master and PHD theses.
equivalence in impact everywhere?
15/120/.6 everywhere and anywhere. That is what I am referring to as a universal posture.
There is a difference between making a determination about how much energy an individual (or other societal unit) should use responsibility and making an informed decision about what percentage of passive solar gain you should leverage for your particular climate before you start creating temperature swings that make it difficult to maintain living conditions acceptable to most. And this concern is not limited to the typology of a single family structure.
PH is a subset of passive solar design not an entirely new development.
Sure you can make an argument that people who live in more extreme climates should be more Spartan. I tend to agree. But why a universal specific heating demand? The specific overall energy demand can address this concern?
It would seem to make sense that if one were to modify the standard for severe climates, that one should also modify it for less severe. IOW it should be difficult everywhere. An 'x' percent variable tied to HDD+CDD.
Interesting. When you put it in those terms. I like the way you have qualified it also, in terms of the occupants' usage patterns. I think in your original blog entry, you may have mentioned Co2 footprints - and for definite, the usage pattern side of the equation can dominate totally there. It doesn't so much in houses, I have my hunches, since everyone needs a certain degree of comfort - and if we don't now - wait until we get older, or are trying to keep the kiddies warmer, or great aunt so-and-so has moved in, or whatever. But in terms of transport, it's amazing the impact of changes in usage pattern.
For instance, for the past two months I have driven by automobile everyone I needed to go, without exception. For the last decade prior to that, I cycled almost everywhere I needed to go, and took public transport. It just so happens, that I have changed city, and also am studying at night time. It got to a stage, where I hadn't enough energy any longer (no matter how many choclate bars I burned), to peddle home from university at 10.00pm in the nightime, in the freezing weather.
So there was a change in consumption of fuel, and subsequent emissions, from a point of view of my own lifestyle change. It happened out of the blue. I guess, in architectural terms, the only comparison, that one could draw, is if a window got broken and one didn't fix it. Or one got into a habit of no closing the front door in winter for some reason. Apart from those radical kinds of changes, I cannot think of anything in architecture terms that is as sensitive to change of usage pattern - as the example of me, and the automobile, in the last two months.
But of course, then there is the opportunity side also - suppose that 10% of people who drive automobiles todays, even cut down on their vehicle usage by 10% - and used public transport or cycled. That would make some sudden change, in the overall scheme of things. However, my suggesting that kind of initiative, I know, will get peoples' backs right up - and say, he is shoving us around, and telling us how to live our lives. They would have a point I guess.
Driving around the city in the past couple of months though, has made me notice, how short some of the distances are, that some people drive. Like if they want to go to a store across the road - they drive. There is something else I have noticed also. The footpaths and pavements etc, between them and their destinations, over that short distance, are often terrible - and nobody, nobody ever seems to bother about it. That is, if the pavements and crossings etc, and general town planning was somewhat better, then walking and cycling wouldn't be so difficult. It also struck me, in my driving around the city, how many people I think prefer to burn some gasoline, because they know, when they get home to their family they will not be tired. That is, they will have some physical energy remaining to play with their children etc.
There is that too. That people use fossil fuel transport, even though it is expensive and nasty - because that is a life choice they have made - to improve the quality of interaction, and time spent with loved ones at home. Being a young single guy, with a bicycle, for the last decade or two, I didn't notice those things so much, as I do, as I get older. I still won't part with my bike though. Not for a long time. I don't care much for the rage that people experience when driving on roads. When I am cycling to work or anywhere, I encounter a lot less of that traffic, and rage. I am simply in my own mind, and thoughts, and float freely along, whatever the traffic, whatever the weather. I guess, I just like that.
Mike, if you ever get an experience to work for a run-of-the-mill, commercial, real estate company. You know the kind, who make money for their investors, and chip away at their business bit-by-bit, and aren't too flashy. That is, they don't get on the cover of architectural magazines etc.
You will find, they are very keenly aware of how big named architects look at them. The big named architects look down at them. If the big named architects do a commission for them, they see it like: This is my project. I'm the big named consultant architect, doing this meagre, miserable real estate firm, a big favour, by putting my name on this project. It's a lot like that, and if you work for the run-of-the-mill real estate company, you begin to see it very much. It's worth getting that experience at some stage in life, I always say. It's the same with green, and non-green architects too. In general, consultants will tend to forget whose project, it actually is. Even the very best designers, seem to fall into it.
The thing I try to do now, with a client, no matter how modest they may be - even if the project isn't something I feel excited about - is to remind myself, the client at least deserved a minimum level of respect, that is their project. Their project, and not my own. After, that, I don't believe there are too many big mistakes one can make, in terms of professional ethics, in dealing with a client. But there is always that one big mistake, we can all make, at any time - and even the best designers out there in the business do it. And when I make it myself, I always feel quite guilty afterwards, even if no one else does.
Builders in extreme cold climates should get PH certification on a regionally-modified basis because the unified standard is so hard to achieve? Sure, and let's modify federal MPG standards for Texas because everyone likes to drive big cars there.
Let's be clear - PH is a value in the marketplace because it offers a specific, rather demanding energy performance standard for a newly constructed home, wherever it may be, and because it provides a standardized toolkit to enable you to get there. It may make no kind of sense to do it but you could build a PH in Antarctica if you chose to throw enough resources at it. And yes it may not seem 'fair' that PH standards are going to be easier to achieve in San Diego than Calgary, but so what? PH is not about fairness, its value is as a simple standard of energy performance, fairly easy to calculate and very easy to measure.
And if it's no longer that, what exactly differentiates it from the many other grading standards? To mention just a couple: if you want a *relative* energy performance score, one that's not Boolean and gives reward for every effort in the right direction, there's HERS. If you want a certificate of general green-ness, taking a wider range of environmental performance factors into account, there's the various flavors of LEED. Let's not even mention all the localized green building certificate programs that have sprung up across the US in the last decade or so. Broadening the standard may seem the easy way to grow its popularity but at what cost to its fundamental value?
Bottom line: if PH is proving a harder sell in the US than in Europe it's hardly because there aren't climates here very similar to the one where the standard originated but rather because of our much lower energy costs and the disinclination of those who are interested in spendy upgrades (and can afford them) for living in attached homes. If PHIUS wants to take the standard in a different direction from the original concept, that's their business, but I can sure understand why the mother organization would get a little irritable about them continuing to use the label.
Cold climate Passivhaus
For a single-family home to reach the Passivhaus standard in Minnesota or Vermont requires investments in insulation that are hard to justify from an economic perspective. The problem is often referred to as the problem of "the last $10,000." Sure, you can spend the last $10,000 on insulation if the standard is important to you -- but you won't be getting many BTUs of savings for your investment. That's a waste of society's resources.
My conclusion: it's silly and wasteful for people in Minnesota and Vermont to pursue the Passivhaus standard.
So, there are two possible solutions:
1. A public education campaign that convinces rich people in Minnesota and Vermont that they shouldn't be tempted to aim for a German standard that results in stupid houses in their climate.
2. Changes to the Passivhaus standard for homes in very cold climates.
I don't really have a dog in this fight, so I'm not choosing between #1 or #2.
The last 10K?
I agree 100% that it makes very little economic OR environmental sense to strive for the PassivHaus standard in more extreme heating climates. My point though was that it also makes very little sense to make changes to the PH standard to enable a broader range of homes to achieve no more than bragging rights. It's an entirely voluntary standard, if certification is what you want there's plenty of other appropriate options.
Like you I don't have a dog in this fight, for somewhat different reasons: the total energy bill for my 50 year old house, including not only heating and cooling but also all the usual appliances, is just not for me a debilitating expense: it's about the same cost as an average cell phone plan. And that's after only about 10K in simple, minimally invasive mechanical and thermal enclosure upgrades. There's still no insulation in most of the the walls and half the windows are original single-pane but the roof insulation is six times what it was, the crawl space is no longer open to the atmosphere and my HVAC mechanicals are up to a decent standard. I'm not sure why I'd want to spend vastly more for very little in energy cost savings and a fancy certificate.
And BTW, in retrofit situations it's not the last 10K that's the problem. It's more like the last 50-100K.
Philipp, taking your idea of
Edit; my post following is actually supposed to be in support of PH staying as it us now, rigid.... And more about how the PGH standard would be set up and used..... Someday a better edit.... I am for all these volluntary programs.
Philipp, taking your idea of drawing a line to a workable real direction.
State via PH all and call it The PH Reference. 15 is a control spec. Then build to an estimated number in reference to the 15, say I choose to design to 17. Then have the cert. Guys in and cert. They cert it is a PH 19. Great news, low E for sure. And lastly with E monitoring, homeowners and their building team could post annual actuals. Say 20 in 2012, 19 in 2013, baby born, 21 in 2014... Etc.
Much better system than the rigid PH of today. And actual numbers are what really matter too.
Is the fight worth fighting for?
Martin you said one option would be:
"1. A public education campaign that convinces rich people in Minnesota and Vermont that they shouldn't be tempted to aim for a German standard that results in stupid houses in their climate."
Also you said that you aren`t really in this fight but I am wondering who would benefit from this fight. Here is my opinion on the last $10,000: From right now`s economical standpoint it makes no sense to spent the $10,000. This is mainly because energy is super cheap. If you compare the cost of these last $10,000 for Minnesota climate you are right around at the PV cost to offset that energy. So if your goal is Net-Zero it doesn`t matter where you spent that money.
My point is that Passive House are not stupid houses but rather net zero ready houses that have a tiny market share. We have seen energy star homes with Ach_50>10 and missing insulation in the walls, we have seen LEED Platinum building using slightly less energy as code build house and we seen passive houses using 14" of EPS under the slab....... Pick your fights.
passivhaus leverages passive solar gains
PH's value is not that it is a simple standard. Its value is that it integrates (with use of a design tool - the PHPP) high insulation value, building envelope tightness with appropriate mechanical ventilation, and the leveraging of passive solar gains to radically reduce heating demands. This marriage of measures can be called by many names and it is an excellent idea for heating load dominated climates except Antarctica. Why not Antarctica? Does it really make sense to follow a passive solar strategy in a region that has no sun during the winter?
PH is a type of passive solar design and effective passive solar design measures depend on location.
Martin, have you ever designed a house that costs over a million dollars to construct? By yours and my standards these are rarely smart houses. If someone is going commission a huge and/or expensive home I think they would do more good than harm meeting the PH standard.
Sorry but I believe you're wrong. As I understand it PH is a performance standard in the achievement of which controlled solar gain may play a part but it is not a requirement, and I believe a number of PH projects have been completed in Europe where for reasons of development density solar orientation has not been a contributing factor. The requirements of Passivhaus certification are indeed fairly simple, though the means to achieve it can be complex. The standard has been summarized in just three sentences:
• The building must be designed to have an annual heating demand as calculated with the Passivhaus Planning Package of not more than 15 kWh/m² per year (4746 btu/ft² per year) in heating and 15 kWh/m² per year cooling energy OR to be designed with a peak heat load of 10W/m²
• Total primary energy (source energy for electricity and etc.) consumption (primary energy for heating, hot water and electricity) must not be more than 120 kWh/m² per year (3.79 × 104 btu/ft² per year)
• The building must not leak more air than 0.6 times the house volume per hour (n50 ≤ 0.6 / hour) at 50 Pa (N/m²) as tested by a blower door
By the way, the hypothetical Antarctic building would also require heating during the six months of summer daylight, so some solar gain probably could in fact play a part in its annual heating budget.
One might doubt if the annual heatload would benefit from solar glass in Antarctica.....
The way I see it, if one were developing a standard, it makes sense to develop that is both useful, and likely to be adopted. One could add to the standard that the house must be blue, but then you will always lose out a percentage of people that refuse to live in a blue house, thus limiting the scope of the standard. Passivhaus is a standard that will see wide adoption in Germany since it was designed for that climate, and most of Europe is warmer than Germany.
In the US, we have large populated areas that are significantly colder than Germany. There is a point when you try to shoehorn a building into a spec that was not designed for it, and the result is shall we say, 'non useful ' If you are expending more resources to build a structure than can reasonably be accounted for in energy savings, you have not done anything useful.
The Germans have decided that flexibility is not in their interest. Fine, It is their prerogative.
To 'me' the 'perfect' standard would be one that means it is challenging to build a house in any climate, without any ridiculous artifacts[IE a foot of foam under the slab]. That would to some extent imply a bit of flexibility, which would include making it stricter in more mild climates
Grading on a curve
Grading on a curve to allow for local climate conditions may be a reasonable expectation for a universal energy performance grading system, but it's up to PHIUS and the parent PHI to sort out whether such a system could still go by the name of Passive House. PHI has not so far been famous for its flexibility.
Response to J Chesnut
Q. "Martin, have you ever designed a house that costs over a million dollars to construct?"
I often feel like these Passivhaus discussions consistently miss the big picture. The reason to build a Passivhaus is to reduce the climate damage your building will do over its lifetime by a dramatic and appropriate amount. The energy consumption of a Passivhaus will be at a level of CO2 emissions most scientists say we need to be to stabilize our climate damage and be equitable across climate zones. More energy consumed from fossil fuels, more damage.
10% plus or minus Passivhaus doesn't really matter, but I've seen over and over that a project without a clear certification goal or a strong marker in the ground will creep its way back to 50% more damage really quickly over the course of design and construction. There are other reasons for Certification beyond a plaque on the wall when you're working with teams of people!
So, if you don't mind doing more damage, go ahead and build a less efficient building. Or, start generating a lot of clean power with your building. Fairly simple choices in the grand scheme of things. We need to get to restorative buildings ASAP, not just Net-Zero, but positive clean energy buildings, and we need to stop dodging the big issues and our reasons for building better buildings.
With that as the big picture, are the Germans being "unreasonable"? "Inflexible"? Just because we don't want to spend the money now on better buildings, won't we just end up paying for it later? We might ask the folks in Joplin, Missouri just how much bad buildings cost them after the tornado wave this year.
Graham Wright in Oregon says it well, Passivhaus doesn't have a cold climate penalty, it has a detached building penalty...
Kaplan Thompson Architects
Jesse, PH is great. It cuts
Jesse, PH is great. It cuts personal annual energy costs. But building MORE homes doesn't touch the exponential CO2/ fossil fuel doom graph. Nature will self correct. Just like gypsies moth populations.
Best personal decision anyone can make us to not add population. Don't have kids.
I like PH and PGH and net zero. But you all are nuts to think a few million NEW PH homes will effect the climate positively.
Tech advances are at this point the only way to sustain the population count today of 7 billion at a doubling rate of every 70 years.
Build PH homes and better yet cut your tubes.
A Lake Placid Ubu ale would be a good choice of beverage this evening as any of you contemplate whether tis noble to have or have not, one day.
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