Image Credit: Solplan Review
More Musings of an Energy Nerd
Today’s brief blog — a departure from my usual practice of writing in-depth articles — was inspired by a recent editorial by Richard Kadulski, the editor of a Canadian newsletter called Solplan Review.
In the March 2014 issue, Kadulski wrote, “I have had discussions with some designers and builders that have set out to build in accordance with Passive House principles. When I questioned them, and suggested alternatives that might be easier to build or be more economic, the answer invariably comes back that it’s not an acceptable Passive House detail.
“If Passive House has laid it out, it’s the gospel, and don’t bother with anything else. And don’t bother questioning whatever quirks have been built into the criteria or the software because it cannot be challenged.
“Like converts to a new religion, they seem to lose sight that there are many ways of achieving high-performance, sustainable building.
“If we’re going to make progress to achieve truly efficient, sustainable and net-zero construction buildings, we need to be able to entertain new ideas and take advantage of new tools and materials. It’s great to get enthusiastic buy-in from new participants who will champion the cause — these are vital to help spread the word. But we need to be careful not create a new religion with a set of dogmas that cannot be challenged.”
Rigor vs. flexibility
Any group that sets out to write a standard has to address the inevitable tension between rigor and flexibility. Almost by definition, rigorous standards tend to be inflexible.
Some standards are prescriptive standards — that is, they tell builders exactly what they need to do, step by step — while other standards are performance standards — that is, they set goals that builders much achieve without telling them how to get there.
The Passivhaus…
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37 Comments
¡Que Viva PGH!
Good editorial. Confirms my recent definition of genius - someone who agrees with you but is more eloquent.
A high bar
Martin,
This seems to be a re-occuring theme on the Passive House Standard. I know that some people still have a hard time understanding that the focus is on envelope goals.
"The fact that the Passivhaus standard (so far) forbids designers to use PV arrays to achieve their goals is a significant source of the tension that Kadulski alludes to."
If this is the area that Kadulski has trouble with, then to me, it's just a matter of his not agreeing with the standard. Just because you have renewable available should not mean that you get to lessen the envelope quality. Why would that make sense? The loads still exist when the renewables are not available. If it's a cost issue, then fine, it's a cost issue. Don't try for the PH standard. But don't blame the standard for your loads.
There are growing portions of Central Europe that have moved their codes to near PH. PH thrives in these areas. Germany will be close to a majority of it building loads being met by renewalbles soon. The reason for this success is not that they can fan out so much PV surface area. It is because they have also systematically reduced the loads. This success has not been accomplished by "an act of faith" or religious fervor. It's accomplished by envelope work.
I don't think that adding PV generation into the certification in order to reduce envelope requirements does the Passive House Standard any service. If PHIUS wants to make PHIUS + easier to reach, or people want to build PGH's, then great. However, lets be honest. The loads remain even when you satisfy them locally.
Response to Albert Rooks
Albert,
You are implying that the Passivhaus standard is an envelope standard. It is -- partly. But it's more than that.
The 0.6 ach50 part of the standard is clearly an envelope standard.
But the 15 kwh/m2*yr is not an envelope standard. It's an energy budget.
If you believe strongly in the envelope standard part of the Passivhaus standard -- the 0.6 ach50 part -- that's fine.
But when it comes to the energy budget part, I see no reason why Passivhaus adherents are so reluctant to consider that it sometimes makes sense to satisfy an energy budget by using PV -- especially when PV is much cheaper than some of the methods chosen by Passivhaus designers to achieve the energy budget without PV.
Energy Budget/Envelope/Response to Albert
Martin,
In your eagerness to find fault with Passivhaus you have jumped the gun in response to Albert. Not only is the airtightness standard part of the envelope standard but so is the energy budget. Passivhaus, and I think you know this, requires almost thermal bridge free construction, meaning reducing conductive as well as convective losses through the envelope. You don't reach the energy budget in most climates with space conditioning needs without significant reduction or elimination of thermal bridges.
In your focus on present-day costs and the building alone, you also seem to be losing the forest for the trees. The idea of building green is to reduce environmental impact. I think you might agree, if you thought it through, that a building that requires much less heating and cooling energy with a smaller PV array has a lower environmental impact, especially when you consider that most of what is required is smart design plus a more careful style of building.
Also re: losing sight of the forest, Dr. Feist is try to transform the building supply industry in Europe and gradually elsewhere by requiring for certification that building envelopes be built (including ventilation equipment), essentially "right". The costs come down as the building supply industry starts to change to meet the new standard. You are focused on present day costs and don't seem to understand this game plan of creating a high quality building supply industry that when it scales up, will deliver lower costs. It is very likely that North America will eventually follow Europe in the reduction of additional upfront costs for Passivhaus, once a certain volume of projects is achieved.
Overall, the Passivhaus standard and green building more generally requires critics, but it helps if those critics keep the bigger picture in focus. It seems to me you have an "itchy trigger finger" when it comes to Passivhaus that goes beyond constructive criticism or at least shows that you don't "get" the basics of what is going on.
Easy killer
True believers have a dangerous history. There's more than one way to skin a house.
Energy Budget
Martin,
Yes the 15kh/m2 is an energy budget. Where we diverge is that you're proposing that the budget is satisfied by partial contribution of renewables like PV. The PHI standard (and the current PHIUS certification) requires that the envelope still be detailed or modeled to the "budget" and that any excess that is created by renewables is "on top" and an additional benefit.
While I don't disagree that it's great that renewables are added to a project and this is a benefit and reward, the point of PH is to reduce the loads.
I understand that it seems excessive and that it makes sense to count PV, but when you approach it this way, you are only offsetting loads. The tendency with this approach will be towards making up the budget with PV and not insulation. That's fine... It's just not meeting the Passive House Standard,
I get your point and certainly respect it. I hope the middle markets move towards this as quickly as possible. California is taking great steps towards this and NZE.
I still advocate for the high bar and the envelope (insulation, glazing and airtightness) because to me we are better off demonstrating that PV loads can charge electric cars and offset plug loads rather than be used to make up envelope losses. We are just entering a period where electric vehicles will be in use enough for this to be practical.
There is a lot more here to consider when the charging benefits from renewables is not diverted to keeping unoccupied daytime homes cool in sunny areas since they are better insulated. Some homes can go net positive when the budget is met by insulation+airtightness+glazing.
While you may argue that it makes a PH project harder to adopt or reach, I argue that when you do get a project to reach it, your PV output is in a better position to be used outside of the envelope.
Reply to Dan Kolbert
Dan,
Your true believers approach is still puzzling to me. There is no act of faith or a need for "believing" here. It's simply deciding where you spend your resources and to what you allocate the output of your renewables.
As a builder you make decisions like this on every project. As a proponent of PGH you are advocating for what is "pretty good" and what is "not good enough" and what is "excessive to PGH". Again it's not a faith based decision that led you to this standard, I'm assuming that it was a series of rational decisions on the best steps to reach your goals. If the PGH goals are different than the Passive House Standard, then they are just different. I'm happy that both exist.
Dan
Long live the Pretty Good House!
Reply to Michael.
I'm with you until it comes to this: "Dr. Feist is try to transform the building supply industry in Europe and gradually elsewhere by requiring for certification that building envelopes be built ... essentially "right".
What are the basis for the Passive House standards that make them objectively right? Aren't they essentially arbitrary however much you may like the results?
Albert
I'd be quite happy with any number of standards to choose from too, but Dr Feist is lobbying for his standards to become the standard and then what choice will we be left with?
Reply to Malcolm
We all "like what we like" and there are a number of standards to choose from. I don't think you have any worry about being forced into a particular standard, other than code minimum, and only in some states in the US.
Even though I am as Martin generously puts it: A "passive house adherent", I like the fact that the other standards exist and thrive. To me that's the beauty of a diverse market place with competing standards. They are all roads leading to reduced loads and a better chance for the future.
Reply to Malcolm
Passivhaus is based on building physics as much as possible. You can measure air changes per hour and you can model thermal conductivity (and measure it if you really want to go to town) using THERM. In selecting the threshold numbers, Feist was trying to hit the point of diminishing returns with these standards though it appears now that it is relatively easy on new construction to hit 0.6 ACH50 and he could have even set a higher bar if he wanted to. The standard is also "wise" in that it is not trying to passively heat or cool the home during the most extreme weather...it is built with the understanding the concept of peak loads.
There are so many benefits to building tight, ventilating right, and reducing/removing thermal bridges that it is not a stretch to call it simply "building right". We also should be building more components in factories and assembling them on site and this makes it even easier to build right and achieve Passivhaus along the way.
But there is no pure "objectivity" in any building system either. Building a building is a "performance" and creation of a new reality. In that creation, the values of the builder, architect, homeowner are expressed...Feist is expressing values that I agree with that are based on physics to a great degree as well as on conscientiousness. Don't you want to be a conscientious in your building endeavors?
Response to Michael Hoexter (Comment #5)
Michael,
You wrote, "The idea of building green is to reduce environmental impact. I think you might agree, if you thought it through, that a building that requires much less heating and cooling energy with a smaller PV array has a lower environmental impact, especially when you consider that most of what is required is smart design plus a more careful style of building."
Of course, GBA agrees strongly with both of your statements. I think it's fair to say that all of us involved in this discusssion:
Believe in reducing our environmental impact;
Strive to reduce thermal bridging through the building envelope;
Strive to design and build homes that require much less heating and cooling energy than the typical home.
If you build a new Passivhaus building, you may or may not be aligned with these goals. The trickiest one is "reducing our environmental impact." In many cases, it makes more sense (from an environmental-impact standpoint) to continue living in a small apartment in an old 1930s apartment building than it does to build a new Passivhaus. But you know that.
Even if there is a situation that calls for someone to build a new home, the Passivhaus standard doesn't always allow the designer to minimize environmental impact -- because in many cases the PHPP modeling requires levels of insulation and expensive windows that add $30,000 to the construction cost -- money that would be better spent on something else (perhaps a PV array?).
Michael, you note that "Passivhaus requires almost thermal bridge free construction." But many environmentally conscious builders have been aware of the problem of thermal bridging for decades, and were building in a way that minimizes thermal bridging for many years, long before Wolfgang Feist had his first conversation with Bo Adamson. When I built my house in 1980, I installed a continuous layer of EPS on the exterior side of my wall sheathing, specifically to address thermal bridging. Passivhaus designers didn't invent the focus on reducing thermal bridging.
Here's where the comparison to religious dogma enters the argument: you posit that we should strive for many high-sounding goals: reducing our environmental impact, building homes that use less energy for heating and cooling, and reducing thermal bridging. But mentioning these goals doesn't provide any evidence that Passivhaus standard is the only way to achieve these goals. That leap requires a quasi-religious conviction. It ignores the rest of us -- other builders who have been striving for these same goals for decades.
Response to Michael Hoexter (Comment #12)
Michael,
You wrote, "Passivhaus is based on building physics as much as possible."
Here's the good thing about physics -- it applies to all of us, whether we trumpet that fact or just accept it silently. It even applies to ignorant code-minimum tract-house builders.
You wrote, "Feist was trying to hit the point of diminishing returns with these standards."
I'm happy to stipulate that Feist was indeed trying to do that. It's even possible that he succeeded -- at least for the climate in central Europe and for German and Austrian construction costs.
But the climate in New England is different from the climate in Germany, and so are our construction costs. There is absolutely to reason to believe that these differences -- differences in climate and construction costs -- can be ignored (certainly not by any reference to physics).
You have acknowledged that 15 kWh/m2*yr is, indeed, an energy budget. So why should an energy budget developed for the climate of central Europe be applied without adjustment to other climates, especially when the result is deviation from one of Feist's stated goals: achieving a balance between heating cost reduction and (as you put it) "diminishing returns"?
Achieving this magic point -- a balancing act between heating cost reductions and diminishing returns -- is an admirable goal, but Feist's chosen standard is arbitrary. It is not physics-based. The true determination of this magic point requires attention to climate, which differs from one location to another, and attention to the prices of insulation and windows at the local Home Depot. That's not physics -- it's economics.
PHPP
Couple myths in the USA, #1 Europe is the standard for energy efficient homes. #2 Energy efficient homes cost more.
I thought about purchasing the PHPP but decided not to waste my money after dealing with them. I am in the final R&D stage of Hempcrete. When I first considered it the European suppliers were quoting insane prices for the shiv and lime binder shipped from UK, New Zealand, and I had discussions with one "technical adviser" I could tell did not know what he was talking about. One "Sales Engineer" told me the USA produces lower quality lime which is false. I learned from reading publications on the National Lime Associations website it is the other way around, we produce a higher quality lime with less silcates or impurities or "fat". So now I do not need to import heavy bags of junk lime form Europe since it is not of a "higher quality" .....The type(N vs S) lime they suggested is wrong too as a DIY mix and you do not need Portland cement. I think they want us to fail so we can see we need to buy from them or they just don't get it nor the USA standards which are different than theirs when it comes to some materials and testing, QA.
Now they are coming to CO where it is legal to grow, spread the BS in hopes of making European sales on the lime as a last ditch effort before we are sourcing all we need locally, less carbon foot print. By the way Hempcrete absorbs CO2 as it cures, is negative CO2 they will try that sales pitch on you too justify the shipping CO2 but, the fat hydraulic lime they produce is less effective.
It took ALOT of research into some complex chemistry and an ability to understand it and Design Engineering I am still testing, but it is looking like my final envelope cost will be 1/3-1/2 mainstream 2x 4 stick construction here and I will have a much better toxic free tight envelope.When I first started and listened to the Europeans my cost was 2.5 times higher than local mainstream. I didn't need PHPP to help me with that, I had to weed through European lies to get there.
It is just not about the envelope either, the internal structure in my design works with the envelope and HVAC if any making it very difficult to determine loads. I am using a different natural material wall from local resources, I believe my final cost will be lower than mainstream too.
Next week I am in touch with some CO farmers that have there first crop, perhaps I can bypass the expensive machinery they do not have yet to separate the chiv from the fibre, make it work so I don't have to buy it from Europe. That may get me down to 1/4-1/2 mainstream.
Just goes to show do not believe everything you hear, Europe is not necessarily the standard, we can learn from each other, knowledge is power.
Michael
"Don't you want to be a conscientious in your building endeavours?"
How am I supposed to answer that? Surely the real question we are discussing is whether the only way to do it is to adhere to Passive House standards.
The envrionmental impact of a PHPP house in Germany...
... heated with resistance heaters in the ventilation air stream (as many have been), is higher than that of a code-min house in Quebec heated with mini-splits, due to the dramatically higher fraction of coal burning that goes in to that 15 kWh/m2*yr than the grid-power in Quebec, which is on a VASTLY renewable (nearly all-hydro) grid. (Or even higher-carbon Ontario, next door.)
The source and environmental footprint of the energy used matters:
http://canadianenergyissues.com/wp-content/uploads/2014/01/Germany-vs-Ontario-CIPK.jpg
Rooftop PV arguments suffer from the same issue- Net Zero Energy doesn't necessarily mean zero-carbon. The energy used for space heating in an NZE house is typically going to be at night, and during the lower PV output season. There too, the energy sources during the hours when energy is actually drawn matters far more than how much the total net energy is. Yes, putting PV on the grid is (usually, in most cases) a good thing, but it's not the only thing. The Net Zero is a standard, but that too is somewhat arbitrary- it's less about the carbon footprint of that particular dwelling than it is about the net utility cost. Net zero energy/ cash is simply not the same as a net zero environmental load.
Yes, the high carbon content of the German power grid is falling, and in 50 years might be near-zero. But there are many places in North America where the electricity is already largely zero-carbon TODAY. The financial crossover of lifecycle diminishing returns also depends on the retail price of power, which is also much cheaper in the nearly-carbon-free provinces & states than in Germany (by more than half), and the outdoor temperature averages are more extreme, which puts the financial crossover point on the building envelope in an entirely different place. There's no magic in 15 kWh/m2*yr regarding either the environmental or financial aspects of the building- there is no one perfect number that applies every where and for all time, and that's where the arbitrary nature of that standard can (and should) be questioned.
It's well worth the exercise to figure out what makes the most sense in individual locations/grids, and not merely hew to a standard that was based on some other set of conditions. Even not-so-hydro-lots-of-natural-gas New England's regional power grid today is substantially lower carbon than Germany's is likely to be in 2030, and dropping year on year. The ideal xx kWh/m2*yr will vary in both time and location, and will vary quite a bit.
Dana
Fascinating analysis - as usual.
following ...
Dana : and then you add on the Co2 footprint for the additional insulation and materials used to pursue the standard in a harsh climate such as zone 6-7 which pushes everything even further down the eco-nonlogical road...
The "green" electricity here in Quebec and its cost to homeowner pushes the PV payback period beyond any attractive period. The recent mini-splits COP and low temp performance combined with a very low power rate does exactly the same for any extensive energy measures.
I agree with you about the ideal kwh/m2 being only possible to determine for specific situation,
that is the PH standard demise.
NetZero is not far behind in anything but the few remaining high carbon energy states and provinces. Slapping large arrays of PV on a deficient building is not the answer.
Terry Lee : are you judging all of EUROPEAN people by your handful personal interpersonal experiences ?? Are you smokin " lime " ... i stopped reading at half your post because i already had hard time to breathe through all the dust :p
read a few times :
There is something to be learn of every individual.
Right now it seems that Europeans are much less "individualistic" than we are in NA ,
a thing we should learn from them.
Even though some of the current ideals aren't 100% good, at least the effort participation rate is much higher there than here.
Wasn't F150 still best sold vehicle in the last years ?? that says alot by itself.
Watch a few videos of construction workers in Germany, UK, Austria, Switzerland etc.. and tell me how efficient they are compared to local Canada/USA workers.
Michael Hoexter: read Marting and Dana's posts a few hundred time as your homework.
As much as we should appreciate what the PH standard as brought up to the table ,
it will need to be altered for climate and carbon or it just won't work at all.
You will see that almost all projects in zone 6-7-8 done to meet PH or very close to it, share 1 thing in common ... very very high price .
Mainly because to meet the energy criteria you need to push ridiculous envelope insulation values.
And as you might know, ridiculous is not so good.
Dana - where are you going with this?
Dana,
I've read your post a couple of times now. I'm not sure what point or solution you're trying to make.
You seem to be arguing that the power generation carbon position is better in some places. That Germany might be near zero in 50 years. That cold areas require more insulation beyond the economic equilibrium.
Yes some places are cold. Power is cheaper here vs Europe. Yes we have more hydro ( I guess...).
I agree with you that everywhere is different. And that it would make more sense to have a highly customizable local solution. It's easy to point these things out. Harder to solve them.
So what is your solution? An "Anarchy Standard"? Sounds fine. Just tune the envelope to balance co2 - PV and $ cost to hit the local sweet spot.
You call them "PHPP houses". I'm not sure if you like the PHPP or not. I like it a lot. So far it seems to be the most reliable modeling tool available (for low energy buildings). Combine it with a good climate file and you can get your H/C loads pretty accurate. It's given thousand of modelers in North America a "newer-better-sharper-tool" at less than $300 for a permanent license. Not too shabby.
Response to Albert Rooks
Albert,
All over North America, there are energy-conscious builders who want to build low-energy buildings with a small environmental impact. Some of them have been active for decades. Most of the buildings they build don't meet the Passivhaus standard.
In your response to Dana, you asked what his point is. I won't try to speak for Dana. But for me, his key point was this one: "There's no magic in 15 kWh/m2*yr regarding either the environmental or financial aspects of the building -- there is no one perfect number that applies everywhere and for all time, and that's where the arbitrary nature of that standard can (and should) be questioned."
If Passivhaus designers acknowledged this, of course, it would make it harder to insist that the Passivhaus standard makes sense everywhere in the world.
The Reality
Being environmentally conscience in builds is not as easy as it looks in literature. My efforts to reduce OPC (Organic Portland Cement ) by using substitute materials of similar cement type properties, such as Pozzolans made from fly ash is not going well. Pozzolans and fly ash are rarely found-produced in the USA, Graymont told me the EPA is driving fly ash cost up. They do not supply it to local feed and seed nor big box stores. Quickcrete stop making their “Portland/Pozzolan” mix back in 1997 although it is still on the MSDS. When I called them they had no idea what I was talking about, nor do my local concrete companies. Magnesium Oxide is another that is hard to find. These materials are readily available in Europe. Even if I could find them there are no USA standards to test a proprietary mix of my own, just as there are no USA standards for hempcrete, or a lime binder, so it is a free for all out do as you will and tell the public you tested it in hopes they never ask to what USA standard, and hope European standards will satisfy them and the AHJ. If I did not live in a state with no Energy code I would not even try hempcrete as an insulation. So far the AHJs are completely ignorant to what it is, as are the Real-Estate agents, bankers, insurance agents. Trying something like this that is part of mainstream in Europe is a real challenge and risky since I have no real data on performance (r-value etc). As I said hempcrete is no voc and CO2 negative and a great way to design passive house. I hope to keep OPC out of floors using limecrete, walls using hempcrete, both natural with high IAQ. Foundation I may not have a choice and have to use OPC for strength.
Now American companies such as Graystone have jumped on the lime binder BS bandwagon bagging and selling their own version to compete with Europeans going after the US market I learned yesterday, but you can purchase theirs for $30 50 lb bag that vs Europe for $55, neither tested to US standard ASTM C-70. Quickcrete, etc will follow with word that Europe is out to stock the big box stores with theirs. My blend $10 bag putting me at 1/2 the cost of mainstream here.
Unfortunately I do not think most of my new construction clients will care about the carbon foot print, nor energy bills, nor will they pay for it in purchase price. Last weekend I walked some clients through a home I am rehabbing, explained I was using low VOC paints and carpet, non seemed to care. Our rehab business gets that response often, client with the $ is the boss!
I hope to appeal to the younger generation especially the ones with children, with less income. I think IAQ and a low mortgage will sell better than low carbon foot print and utility bills.
Europe did not give birth to Hempcrete or many other natural low carbon foot print, low VOC, building methods they use today. The US stopped using them as a result of the Industrial revolution. I guess we say Europe has more experience with them and standards. From what I gather Europe also has different materials more readily available due to supply and demand. I bet quickcrete would still stock their Pozzolan mix if it was understood and sold.
Strawbale is another great way to get there if you can find construction grade bales at low cost. I could not, needing a contract with a farmer for next season and clear quality control guidelines, although chapter R and S of 2015 IRC has code now. The European settlers gave birth to it and the world known "Load Bearing Wall" in NE here in the states back in the early 19th century many of which still stand today. I visited Piger, NE recently destroyed last June by twin deadly EF4 tornados, child died in a 'manufactured home" SB homes still stand 300 miles to the east.
Gypsum block is another Europe still produces no VOC we stopped back in the 1900's chose manufactured drywall instead accounting for the largest mass production of Gypsum in the world.
Jin : stop putting words in my mouth, I stopped reading your 'dust' at that point too ;) Since you can't read I'll repost my last paragraph...
"Just goes to show do not believe everything you hear, Europe is not necessarily the standard, we can learn from each other, knowledge is power."
And I'll add it's one thing to write about being environmentally friendly, another to make it reality in your builds. I'd be interested in seeing in detail how PHPP factors the above into the equation?
Where indeed... (response to albert rooks,#20)
Where am I going with this?
If the PassivHaus standard purports to be near the optimal balance point of carbon, cash & comfort, for all locations & grids for all time, the underlying assumptions are suspect.
It makes a difference that a kwh in 2014 in Quebec has about 2% of the carbon content of a kwh in 2014 in Köln.
Even if the grid in Germany becomes as carbon free in 50 years at Quebec is today, a PassivHaus built in Darmstadt today has a higher lifecycle environmental footprint than a code-min house heated by heat pump in Gatineau. The carbon balance point on further building envelope improvement is in a VERY different place, when the Darmstadt house has a higher carbon content to the building materials, and carbon footprint of it's marginal energy use in the first 5 years exceeds that of the code-min Gatineau house's first century.
It makes a difference that the cost of grid-power in Quebec is 1/3 that of Germany, which moves the fulcrum on the cost axis dramatically too.
I'm happy that the PassivHaus tools predict energy use as well as they do. But the notion that 15 kWh/m2*yr is strikes an ideal balance in Quebec (even if it does in Germany) is not intuitively obvious. It fails the mental math test (and would probably fail the lipstick on mirror math as well).
"So what is your solution? An "Anarchy Standard"? Sounds fine. Just tune the envelope to balance co2 - PV and $ cost to hit the local sweet spot."
Tuning the envelope to balance these factors seems to be what the PassivHaus standard is about, but without apparent acknowledgement that the fulcrums on the different axis' will vary widely (orders of magnitude, even) by both location and time. I don't deign to propose a simple universal standard, but I do advocate a more nuanced approach recognizing the differences in energy source carbon and actual energy cost.
This cannot be reduced to a single annual net energy use or annual energy use per square meter type of number, but it matters. Getting carbon emissions down on a lowest-cost basis is more important. While these energy use constants may be interesting stakes in the ground, they are ultimately not relevant numbers to be focusing on. Embracing the complexity isn't the same as "Anarchy".
Energy use is simply not a very good proxy for environmental impact or financial cost, and reduction in energy use for it's own sake is a hollow exercise without the context.
(edited to add:)
The Energiewende context still has a way to go, despite the impressive rate of distributed renewables penetration in Germany. Coal (particularly lignite, but also hard coal) is still king in Germany, and will continue be for some time to come- the fuel behind 46% of all power generated in that country in 2013:
http://us.boell.org/sites/default/files/german-coal-conundrum.pdf
Retail electricity in Germany is priced at about 35 US-cents/kwh, to Canada's average of 10 US-cents/kwh:
http://cleantechnica.com/2013/09/30/average-electricity-prices-around-world/
In what universe does a prescriptive annual energy use constant that may make financial & environmental balance sense in Germany continue to make sense for homes in Quebec heated by the near-zero-pollution power grid of Quebec? I'd really like to know how argument is supposed to work!
Reply to Dana Dorset #23
Dana,
Thinking of a standard based in "anarchy" made me smile (and I could always use more smiles). It's the basis of an extremely localized "tuning" of the project combined with individualistic "tuned" goals of what amount of energy is acceptable. It's so "non standard" and individualistic it seems perfectly American in that it refuses to agree on common ideology and is "ruggedly independent". It therefore appears to me as largely Anarchistic.
-The "Anarchy Building Standard" I like it. It's an updated "halfassivehaus". 1, Pick your location. 2, Pick your envelop loss range, put your selection into the check box for my reason for the project:
(A) I am a Climate Change Deny(er) Therefore I want to tune the envelope to offset future energy costs only. Spend no more on passive means than i can get back in 10 years. I'm using 10 years because I may be dead at 11 years. Why spend more if I may not be alive? The earth can go f**k itself.
(B) I only have limited funds to work with. My bloodsucking bank won't finance my project because I'm spending more on the envelope that it can get in foreclosure.
(C) I like PV and other fancy things that show off how "hip" I am. I'm going to create an adequate envelope and reserve a big budget for PV so I can look more green than my neighbors.
(D) My local grid is hydro based so I'm taking a pass on the co2 argument of passive elements vs low co2 generation. I am certain in my prediction that things will not change and usage will continue to be met by present day methods and usage.
(E) I am smarter than everyone else so why adopt one of those rigid standards? What the heck! it was created in a colder or warmer, farther away place than I live. Why should it apply to me? My climate is "different".
So there you go... Tune the dials and localize the project. I'll need to come up with a certification plaque to be displayed onsite. Perhaps:
This Project conforms to "The Anarchy Building Standard" and confirms that no one tells us what we "have to" do.
I contrast that to what I read in Passive House News this morning with a link to: http://passivehouseplus.ie/news/events/world-s-largest-passive-house-district-presented-with-award.html
An excerpt from the above link about an entire neighborhood built in Passive House:
“High energy performance construction is establishing itself in an increasing number of countries. An entire city district built to the passive house Standard, however, is until now unique,” comments Dr Wolfgang Feist, director of the Passive House Institute. “In this way, the City of Heidelberg is delivering a blueprint for the future. The European [Energy Perfomance of] Buildings directive dictates that so-called nearly zero energy buildings are to become the norm by 2021. With the passive house standard, Bahnstadt is already fulfilling these requirements.”
What strikes me about this is that there is a successful program that has a high adoption rate, complete educational program, and a complete set of tools (PHPP, THERM, 3rd party certification).
Contrast that to what I expect is going on at BSC summer camp this week is: continued whining that "my climate is different" and it's hard to reach PH level and therefore we need an adjustable standards for those hot or cold areas of North America (it's not like Greece or Norway... It's different!!.)
Customizing solutions is one thing to consider, however, all climates are different. While multiple standards can create an easier path to project success, there is no argument that can be made to the fact that the single Passivhaus Standard developed by Dr Feist -has and continues to- transform the industry on a global scale. That's the thing about common goals: Argue about it as we might, it's the centralized standard that has us engaged and is the core of the argument.
Response to Albert Rooks
Albert,
Your description of those who don't follow the Passivhaus standard -- climate change deniers, cost-cutting homeowners, superficial people who only want bling, stubborn people who feel confident that they can predict the future, and arrogant people who think they are smarter than everyone else -- is perhaps intended to be funny, but it is disservice to the debate and dialogue happening here at GBA.
It might also be interpreted as an example of the dogmatic rigidity (and scorn for non-believers) that Richard Kadulski discussed in his editorial.
Passive
I think Passivhaus has something to do with Passive House. That the goal is to create an ideal house with minimal moving parts.
Different strokes for different folks. Up may not be down, and that is okay.
The Boston Way...
As we say in Boston, traffic laws are only "suggestions". Anyone living in the narrow tangled streets of this city knows how crazy this is, but there's more truth to it than most of us find comfortable.
Passivhaus was decidedly not developed in Boston, but rather in Germany, where traffic laws are definitely followed. If you want your building standards to be "suggestions", than go ahead and promulgate the "North American Kind of Sort of Passive House" standards, just don't call it Passivhaus. It's simply a different mindset, what are simple standards to follow in Germany are "dogma" and "religion" in the US. Why? Because, just as with Bostonians struggling with traffic laws in their fair city, Americans have a real hard time with performance standards: "Can't we cut corners, can't we make this or that cheaper, can't we make this easier to build?" You can see the cumulation of these differing mindsets over several decades by just take a quick building tour anywhere in Germany for a few days, and then do the same in the US. As my German friends only half-jokingly state, "The US is the most advanced Third World country in the world..."
ok let's clarify a few things
PH criterias
- Windows
I do not believe that there is any problem with using PHI windows requirement for any climate,
it is already possible to manufacture windows with the correct performance and more are coming to market soon . PH seems to have some climate specific requirements that are more related to comfort. So this is not an issue .
- ACH / air leaks
0.6 required is possible in any climate and should already be something to aim for , or better.
No problems here either.
- HRV/ERV efficiency and exhchange rates
Also already possible with current products and more to come.
I do not see why anyone would strive for any less if possible.
There are more and more cheaper solutions coming along in the next years.
Done.
What is left now ,
the dreaded energy per area per year
15KWhr/m2a
Do not tell me that it would be very difficult to have adjusted values on that criteria
for different climates in NA, or even based on lattitudes ...
So what is the problem here ?
Isn't that what PHIUS is working on ?
I see it very simple .. it doesn't need to take 20000 different problems in account,
we are talking about adjusting a single value to "better" fit 6-7 possible climates .
( cooling climates possibly do not need much adjustments at all )
I do also not agree with using a signle rigid value for every climate,
it is plain "arrogance " .
As some pointed out, PH standard is doing very good , it is moving things everywhere in the world,
it will help most European countries with their energy economics and it pushes everybody to rethink NOW .
Most "pros" here could run very simple cost/roi and energy/co2 stats for different level of insulations in the matter of a few hours of work, and it could be enough to agree on a criteria modifier for different climates for NOW .
Is there anything else from PH standard that is wrong for our NA standpoint ?
but an arbitrary 15 kWh/m2*yr
but an arbitrary 15 kWh/m2*yr is not a very useful standard, and has no basis outside of the context in which it was developed. """"""""""
Even there, it would need to be adjusted with time, not fixed.
But you are smart Dana , and we all like you have you around so we can ask questions and use some of your idling back processing power :p
it's not that it's hard to hit PH energy use levels...
... it's that it doesn't always make sense, either on a carbon emissions or lifecycle cost basis.
Lot's of people can do the arithmetic- it's not hard math. Building to PH energy use levels isn't necessarily hard, just not always justified on either an environmental or financial basis. You don't have to be smarter than everyone else to figure this out.
There's plenty of room for higher energy performance in buildings than current code minimums, even in low-energy-cost green grid locations. But the notion that Feist et al have hit upon THE magic energy-use number that makes sense everywhere and for all time needs to be demonstrated- show me the math! (Even if it's the hard math or requires some physics that's OK, I have a degrees in both. But that doesn't make me the smartest guy in the room- you can even ask my wife! :-) )
In massively-high-carbon-grid Germany they SHOULD be handing out awards to districts that adopt high building performance standards. And there's an argument for Net Zero Energy in other places too. But so what? The prescriptives still need to fit the circumstances. Insisting on adherence to a single number while ignoring the context isn't a mark of good policy. To me it reads like replacing actual thinking with dogma. (YMMV) The environmental footprint of both the energy sources and the building materials matter.
As for "...there is no argument that can be made to the fact that the single Passivhaus Standard developed by Dr Feist -has and continues to- transform the industry on a global scale."
Really? Try these on for size:
There are more code-min houses built in North America in any single month than the sum total number of all PassivHaus certified houses in the world to date. Increasing the thermal performance of average US home by even 1% would have a larger impact on climate change than the entire collection of PassivHaus certified houses. Even the US D.O.E.'s Energy Star Home standard (as tepid as it may be in terms of energy use reductions below status quo) has had and will continue to have a larger transformative impact on how MOST homes get built than the PassivHaus standard, at 1.5 million certified homes (and counting).
https://www.energystar.gov/index.cfm?fuseaction=new_homes_partners.locator
I'd argue that even without pricing the externalities of carbon and optimizing lifecycle net present value would make mere Energy Star look like under-investment in most of the US. But the fact that it's readily marketable to other than hard core "greenies" (over 20% of all home sales in some years), and substantially better performance than code-min houses means it's doing more for the world than Feist's progeny, and has a far larger and more transformative influence on how other homes are built than the PassivHaus standard.
The "global scale" is also a bit of stretch, since over 90% of the tiny number of houses with PassivHaus certification are in either German-speaking or Scandinavian countries- if you throw in the UK it's over 95% of all certified houses::
http://karten.passiv.de/?q=gebaeude&o=true&l=en_EN
Heute Europa, morgen die Welt?
I don't see much evidence of that. One-offs in Siberia or one for the entire content of Africa , or a 2-fer in all of South America does not "global scale" make.
Net Zero Energy is a far easier concept to grasp than PassivHaus, and far easier to implement in many areas (usually cheaper too). Net Zero Energy is now enshrined in California's Title 24 2014 building code, which stipulates that all new residential construction must be net-zero by 2020 with all new commercial buildings net-zero by 2030:
http://cleantechnica.com/2014/04/15/californias-net-zero-energy-building-will-reshape-us-construction-industry/
This is a state which builds more houses per year than all PassivHaus certified homes built to date, and a state whose energy codes influence policy decisions in other states, as well as the US national level. I believe that as the price of grid-tied PV continues to crash, Net Zero Energy will become the broader world-wide standard, and will make more sense than PassivHaus. Unlike the latter, how you get to Net Zero is very flexible- it is left as an exercise for the designer, and is independent of annual energy use per square meter. In most of the world I suspect on a worldwide average a Net Zero Energy approach would end up being lower net-carbon than PassivHaus (but if you have a model that indicates this guess on carbon accounting is in error, I'd love to see that math!)
With ardent inflexibility on the energy use per square meter number my gut tells me that rather than being transformative on a global scale (and thus defining the path to a low-carbon future for the world) PassivHaus may be reduced to irrelevance, a mere footnote in history, even if a cadre of true believers will hang on for another generation. This does not detract from any of the valuable work and intellectual property developed in Darmstadt- it has been a worthwhile endeavor, but an arbitrary 15 kWh/m2*yr is not a very useful standard, and has no basis outside of the context in which it was developed.
but Jin...
... you really need to get feedback from my wife on that. Being halfway articulate in the written form sometime masks the idiot within. :-)
I agree that eventually 15 kWh/m2*yr may become irrelevant even in Darmstadt, but that day is decades away at best for German houses that get that 15 kWh/m2*yr from the wider German grid. There are already local micro-grids in Germany that are dramatically lower-carbon than the national average (eg. Feldheim: http://simonwild.me/2013/02/25/it-can-be-done-german-town-off-the-grid/ ), where fully meeting the PassivHaus spec would increase the lifecycle footprint of new buildings over some intermediate values, depending on how they did it.
But like PassivHaus, I don't expect Feldheim's independent heat + power micro-grid model to become the standard way of doing things in Germany. Micro-grids may become the standard development path in Africa or rural India though, since PV+ storage may already be cheaper than developing large grids with large centralized power generation in locations with scant pre-existing infrastructure to support large grids. India's new government under Narendra Modi seems very interested in testing that thesis, but is also interested in developing large-scale centralized PV arrays. We'll see- Modi impressed the hell out of most observers on his ability to get solar implemented when he was governor of the state of Gujarat, but the national plan is off-the-charts huge in scope.
Reply to Martin Holladay #25
Martin,
Sorry if that was too flip of a post. There are plenty of people who report to me those positions. It's not ridiculing them if they are really saying "to heck the environment I want to insulate because I don't want to buy energy". They are saying it. I'm just reporting it. And I'm not ridiculing them if they don't build their project to the PH Standard. I help them build the project that they want to build.
You might have misunderstood my point. All of these motivations and limitations are often in conflict with ANY high building standard. The irony I'm pointing out is that even a highly localized and customized Building Standard suffers from the same conflicts because there are just so many of them. As a culture we don't like being confined to a standard. I don't think your area even has a code minimum right?
My point is that as Americans we seem to like our concessions to more freedom. Even tweaking a standard so we can count PV into the energy budget. Is it dogma to disagree with your proposed tweak? I hope you're leaving me the ability to say that I think PV should go to plug loads and not to envelope above 15kw/m2 without calling me a perpetrator of dogma.
There is no arrogance in me about the PH Standard. I've not once in this blog said it is the "only" and "best" and I've repeatedly confirmed my appreciation that other standards exist.
I do find it frustrating that you seem to be stuck in the same old trench. My impression is that you'd like to change the Passivhaus Standard to allow PV offsets. Or less sub-slab foam... Or...
It's not yours -or my standard to change. If I seem "rigid" it's probably because my view is to work with the standard as it exists. I like it as it exists. If you (MH) don't agree with it, and you (MH) can't change it, then anyone who disagrees with your wish to change it is rigid? I don't think that's what you're saying, but it is the other side of the "rigid" coin.
Response to Dana Dorsett #29
Dana,
You wrote:
There's plenty of room for higher energy performance in buildings than current code minimums, even in low-energy-cost green grid locations. But the notion that Feist et al have hit upon THE magic energy-use number that makes sense everywhere and for all time needs to be demonstrated- show me the math!
I have no disagreement with this. however I don't think it's the point. We know that this continent is a long way from massive Passivhaus adoption. I don't agree that it makes senses to alter a global standard due to local shortcomings. The better answer is to create a localized answer. However, it's very difficult to do this. Not in the head, or on paper, but in the field with educational programs, common goals, 3rd party oversight. It's not an armchair experiment.
And lastly:
You wrote:
As for "...there is no argument that can be made to the fact that the single Passivhaus Standard developed by Dr Feist -has and continues to- transform the industry on a global scale."
Really? Try these on for size: There are more code-min houses built in North America in any single month ...
Perhaps you missed my point: I'm aware of the numbers you quoted. I understand the small number of Passivhaus projects globally. However I was referring to transformative thinking rather than building. A redesign of the "intellectual position" of the industry here, and on a global scale.
I happened to notice that 3 out of the top 4 blogs in GBA today are about some aspect of Passivhaus or Passive House. Perhaps it's just me, but that I think that means something.
Response to Albert Rooks (Comment #32)
Albert,
I like emphasizing points of agreement. I think we both agree that the categories of homeowners you listed -- climate change deniers, cost-cutting homeowners, superficial people who only want bling, stubborn people who feel confident that they can predict the future, and arrogant people who think they are smarter than everyone else -- are unlikely to build a good house.
Neither GBA readers nor Passivhaus builders fall into the categories you list, and I suppose (if you and I were the type of people who like to sneer) we could both stand on the same side of an imaginary line and sneer at all those people on the other side. But the people you list are really irrelevant to the discussion.
All of us want to build houses that don't use much energy and that have a small environmental impact.
If you're interested in my opinion on building codes, here it is: I think that building codes are a good idea. I think that energy codes should become more stringent, especially in regards to airtightness, and that it would be a great thing if codes began to be enforced. That way, buyers of new homes might be assured that they're getting a quality product.
So I don't think that my discussion of the 15 kWh/m2*y issue has anything to do with your perception that Americans don't like any restrictions on their freedom. You may be right about that characteristic of a large segment of the American population, but that's not what we're talking about here.
And I agree with you that, as long as the Passivhaus standard remains what it is today -- a voluntary standard that builders can choose to pursue if they want -- then it's fine that it is available. It's one approach, and anyone who likes it can pursue it.
But it's also OK to discuss whether the standard makes sense.
A missing piece to this topic
Perhaps what would help the underlying question here is a detailed look at the new standards about to emerge from PHI.
If the discussion is "whether the standard makes sense" and there is significant doubt voiced here that it does not in many cases, then in steps the new "Conservation Building" standard from PHI. I haven't seen it defined yet but my impression that it fills the gap responsible for creating tension to ease the existing PH standard.
You lead with this in your opening theme about the topic. If it's essentially a higher heating load allowance, then I think it serves what my point is: Don't adjust an existing standard that is successful and a high reach, bring an additional standard in as an option.
The success of the existing PH Standard is not in it's metric. The success in the standard are all of the services available brought forward from PHI and by extension PHIUS.
What makes the whole package work is the accessibility to designer training, builder training, modeling tools, product certification, building certification. These are drivers that help individuals come into the field and succeed. They are also strong drivers for industry to build better products. That's the real success of Passivhaus: It builds resources and provides training and success. This is true for both PHI and PHIUS. It's the tools being understood and used more that matter most. It's a common theme to "employ the Passivhaus concepts" on a project to the "extent possible".
So yes, as always we agree on most points. The magic is not in the metric, it's in the delivery. While the metric remains an issue, I expect that the Conservation Standard will fill the gap. If we can get it defined, perhaps this should be the subject of a guest blog post. Any takers?
Response to Albert Rooks
Albert,
I'm in agreement -- especially on these points:
"What makes the whole package work is the accessibility to designer training, builder training, modeling tools, product certification, building certification. These are drivers that help individuals come into the field and succeed. They are also strong drivers for industry to build better products. ... The magic is not in the metric, it's in the delivery."
OK. It's good we agree.
USA Reality
Who’s the smartest in the room? Certainly not the best writer or whom has a talent for assembling fancy words on forums-blogs. Assembling data from a build speaks volumes, as in ACH and IAQ reading from third parties, as well as impact to greenhouse gas reduction in tons. Anyone have data on one of their builds? I’m still designing, not easy, will soon.
I’m heading to a Power Plant in Kansas City, KS today to pick up some fly ash. I also have some Portland cement I am testing with, which I read is the biggest producer in green house emissions from the construction industry. My biggest concern is IAQ since that is what homeowners or my clients come home to daily. EPA has some regulations out there for manufactures, giving them an IAQ rating, some third party industrial hygienist have found to be fraudulent in homes.
Fly ash in the USA, a known substitute for Portland cement, used with clay and other traces of heavy metals we manufacture are unknown in the long term to be a health hazards. If you read the MSDS, yep, I agree you will need to train your contractors to handle it or you as a builder can be sued, along with the long term potential health effects you expose clients to. If I lived in Germany where an abundance on “natural pozzolan” is available, no worries! The Pozzolan has an added benefit of moisture retention, breathability, and permeability. For every ton of fly ash I substitute in my design for Portland cement, I save the same ton of greenhouse emissions.
The coal firing power plant I am visiting to get my fly ash causes 28 deaths, 43 heart attacks, 480 asthma, etc, attacks annually…sales guy tells me I can purchase FA about the same price per pound as OPC. So I am helping this death producing plant profit from its waste?
Where exactly am I supposed to get training on how to design to all this? Every sales guy I talked to, from Europe to the US, is out to accomplish one thing, that is make a sale anyway they can at any expense. You will never get good design training in this mess! You do not have the corporate structure that provides it free of hidden sales agenda’s.
Not sure how many have designed to standards or guides, design, manufacturing methods, field, material specs, supplier capabilities, etc., and have produced a product. I have done it for a very long time in several industries, this is the worse. The best training I have so far comes from aircraft-auto corporate structure, in the building industry from other builders that share a common goal to build natural toxic free building’s that reduce greenhouse emissions. I am in contact with some of the best natural builders in the USA, we agree how far behind we are compared to other countries and industries. I hope to help solve that after the non-disclosure agreements are signed ;)
I cannot say the manufacture of a mini-spit has a low embodied energy, we would have to look at the cradle to grave life cycle. I think some solar passive designs have a better chance.
As I said I don’t need Germany, their standards, passive house, to help me figure this out. Germany has a different environment than we do in the states in many ways. I also do not believe ANY training will make a difference, it has to be the right training from the right source. Some of the technical aspects of what I am dealing with would be very difficult to capture and document. Even if you could it would take time and experience to understand it.
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