TO THE BARRICADES!
Image Credit: Nocturnales
More Musings of an Energy Nerd
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One of the presentations I attended at the Passive House conference in Portland, Maine, on September 22, 2014 was a session called “Passive House certifiers’ roundtable.” The first speaker on the panel, Tomas O’Leary, explained that he usually charges about $2,200 to certify a residential Passivhaus project. He warned the audience that certification is “quite an effort; don’t underestimate it.”
Tomas advised that anyone interested in certifying their Passivhaus should remember the following important steps:
- Prepare, collate, and submit the construction and mechanical details.
- Photograph all critical details.
- Make sure you get an HRV commissioning report.
- Remember that your blower-door test has to be performed twice: under both pressurization and depressurization conditions.
- Make sure that you enter the right climate data into PHPP; data from a nearby weather station might not be good enough.
- Enter the correct U-factors for all of the window components — Uframe, Uedge, Uglass — because each component has to be modeled.
- The R-value per inch of all relevant materials has to be documented. Listing the R-values is insufficient; each R-value requires a document that justifies the listed value.
- Document a 360 degree panorama of the shading situation at the building site.
Is each one of these details really essential for determining whether a house can be certified as a Passivhaus? Absolutely.
If you are in any doubt about this issue, remember that one of the cited causes of the famous divorce between the Passivhaus Institut in Germany and Passive House Institute U.S. was a dispute over the details of the certification documents for a house in Canada. The dispute centered on two points: whether the efficiency calculations for a Canadian HRV…
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88 Comments
Brilliant
I'll get out the mimeograph machine and start printing the pamphlets. Allons enfants etc.
Your #5 about passive solar is simply stupid
Martin,
5. We need to size and orient our windows with an eye to comfort and delight, not passive solar gains
In a cold climate that gets sunny days in the winter, it has been proven time after time that passive solar contributes a lot to meet required heating capacity. For you to make such a blanket statement, and then support it with an "astute analysis" that actually may have some validity, but only in the very specific example given, is actually hilarious, except for the fact that it is a stupid blanket comment, and except for the fact that a lot of people believe everything you say on this website.
Such a blanket comment about passive solar is stupid because:
--you support it based on an analysis of a net zero house. Net-zero house is meaningless, because those houses can be totally inefficient and still achieve net-zero with vast PV arrays. Net zero has nothing to do with your bad argument.
--a tight, well insulated/oriented house, even a passive house, is well served by properly placed/sized/oriented windows (south facing and otherwise). Peoploe have known this for years. Even you know this. For you to say what you did, has to have some other motive connected to it. The only thing that I have ever been able to figure out that may induce your passive solar ignorance is that you live in Vemont, with no winter sun. That really is a poor excuse for spreading nonsense. Passive solar is better than PV, the bandwagon you have jumped on so hard. Windows are the only real expense, and people have to have them anyway. Then, just like with PV, the sun sends no bill.
--Of course there are some cases where the heating load is already so small that passive solar is not needed! But that is NOT the general rule, except in mild winter climates. I retrofitted my house in a neighborhood with heat pumps running all over the place as soon as the night temperature goes to 45F (October, Zone 4, almost Zone 5). At MY house, although fairly tight and insulated, I would still need heat when temps got not much below that EXCEPT for carefully designed/shaded passive solar. Last year, no heat was turned on at my place until the week before Christmas. Again, heat pumps running elsewhere long before that all around my neighborhood. I could go the entire winter without supplemental heat, IF there were as many sunny days as cloudy days, and if the night temperature never got below about 28F.
---in a well designed house the overheating penalty during shoulder seasons is literally trivial. At my house, it doesn't cost me in shoulder-season air conditioning. The shoulder seasons are the ideal times to open windows anyway.
Your comment is just ludicrous. Maybe you can convince other people otherwise, but even with new construction, it is a crime against nature NOT to use passive solar techniques, unless they are just not available. Finally, I know you will come back with a defense of your comment and, sadly, many will believe. I rarely visit GBA website any more. There is some really good information, here, but there shouldn't be the periodic instances of asininity like your #5.
Response to Sonny Chatum
Sonny,
Every house gets some solar gains through windows, so every house is partially heated by the sun. This has been true ever since window glass was invented.
The question is, how big do you want your south-facing windows to be? I say, they should admit as much light as your family enjoys, but not so much as to create glare and irritation. They should frame the view, but not overwhelm the occupants in a way that limits the sense of coziness that all homes need to provide.
There is no justification for making south-facing windows any larger than required for the principles I have outlined above, as Gary Proskiw explained. Fortunately, the south-facing windows that you decide to include in your house will help heat the house in winter. So relax.
If you want to see the effects of your fenestration decisions, use a good energy modeling program like PHPP. Extensive north-facing glass will increase your space-heating bills, as every designer should know. South-facing glass has the benefit of balancing nighttime heat loss with daytime heat gains, as every designer should also know. But installing huge south-facing windows in hopes that these big areas of glazing will "help heat the house" is misguided.
Northern Lighting
Designing solely for energy loads is a mistake (if there is a bit of artist in your heart).
My house had two bedrooms on the north side of the house, lit only by sliding glass door that were shaded and on the NW side of the room. These rooms were dark and uninviting. I put a 4'x6' window facing NE in each room, and was absolutely stunned by the transformation. The outside of the house looked much better too. The driveway approaches from that side of the house, and visitors were greeted by a monolithic, brutalist exterior.
The quality of the light was spectacular and the rooms suddenly became very inviting, almost pulling you inside. The I learned that artists in the past preferred rooms with northern lighting. The sun didn't heat up the room, and the light was consistent throughout the day.
I've made my place a "pretty good house." It's great to know all the best practices and techniques.
But as I was told once, to have style, you should break at least one of the rules.
Thanks again!
Response to Dan Kolbert
Dan,
I'm glad someone still has a mimeograph machine now that we need one. I hope it is one of the hand-crank, non-electric models.
Passive Solar
Martin,
I cannot say I entirely agree with the sentiment in your rule 5, though I won't be calling you any names because we disagree.
There is no particular point you make that I feel is inaccurate. However, to me the underlying tone, or takeaway is that passive solar has (or should) be downgraded in priority. Perhaps that is not your intent, but it is how I read it, which I admit is surprising given the source. This, I feel, is a disservice, both to the industry (movement, whatever...), and to your own efforts to educate people.
In fairness, you ended your point advising us to continue following the basic principles of passive solar design, but omitted probably the most important one. Properly designed overhangs. Moreover, you suggest that a side benefit of not worrying about passive solar as a heat source will limit, or help reduce overheating. This is true, strictly speaking - less glazing means less overheating - but again, appropriate overhangs are what prevent it in the first place.
I urge you to include some mention of this important point in your list.
You would be amazed (or perhaps not) how many people I run into that do not realize how ineffective their overhangs are, yet wonder why their home overheats on clear sunny days. These people are not designers, architects, etc, but they are homeowners. If tomorrow we all stopped buying homes with miniscule southern overhangs, people would stop designing them. It's like drinking and driving, we have to keep putting the message out there. Ad nauseum.
The rest of your list I strongly agree with, and thank you for including links to the past articles. I am in the middle of comparing insulation upgrades and was wondering how best to factor PV into the equation.
cheers
Response to Jason Hyde
Jason,
Regular readers of my articles undoubtedly get tired of the repetitious nature of my writing. To address this problem, I sometimes decide that I don't have to say everything every time I write.
Anyone who hangs out at GBA knows that my nickname is Mr. Overhang. I've been haranguing designers on the topic of roof overhangs for a long time.
You're right, of course. Fortunately, in this article I didn't slip up and mistakenly advise readers that they no longer need roof overhangs. Anyone who wants a refresher course should read the following three articles:
Every House Needs Roof Overhangs
Brick Buildings Need Roof Overhangs
Martin’s Ten Rules of Roof Design
PGH isn't helpful to consumers
Martin,
I don't disagree with the points you make but PGH is a concept designed by building professionals for building professionals. Unless there are specific standards and an independent certification process, it doesn't really help consumers that much. Most consumers are relatively uninformed and need some sort of official seal of approval to have confidence that a home is relatively energy efficient. If these points were to get worked into a standard - like PHIUS - then it could be really helpful.
Scott Tenney
Thank You Monsieur Martin
"Formidable!" as the French say.
From an aspiring owner/builder in zone 4A.
the good guys are....
Martin, Marc Rosenbaum, and the Maine boys doing PGH oh and Dana Dorset.
And of course Bruce Brownell and even me.
Long live PGH.
Response to Scott Tenney
Scott,
Plenty of groups and agencies are trying to address your point.
In California, state officials are trying to use Title 24 (the state's building code) and local code officials to achieve your goal, with mixed results.
The Energy Star Homes program is also trying to achieve your goal.
To some extent, RESNET is trying to achieve your goal, by advising anyone who wants one to get a HERS rating.
Several regional green building programs -- including Austin Energy Green Building, the Earthcraft House program, and Build Green New Mexico -- are also trying to achieve your goal.
Do we need a new certification agency to provide Pretty Good House plaques? Let me think for a moment.... Nah.
Response to Bruce Palmer
Je vous en prie.
What I DO like about the Passive House Approach
is the focus on simplicity for one thing.
It has taught us that we don't need a complex heating system with pipes full of liquids running everywhere through the house. A minisplit heat pump is an appliance rather than a heating system and as such, is much simpler.
PH also places a very high value on air quality and comfort. Often, the triple glazed windows are important for reasons other than energy use. In Vermont, I often find that people want to be able to go away for a month in the winter and not worry about their plants dying and their pipes freezing if the power goes out. Or they really want that wall of glass facing the amazing view to the North.
PH has shown us that there are excellent ways to get fresh air without simply sucking air (and heat) out of the house with exhaust fans and relying on a leaky shell for makeup air. (Still hearing that you shouldn't build a house too tight from builders)
Granted, we don't need PH to show us these things but PH is good at attracting the media attention enough so that air exchange is on more and more people's "must have" lists.
The biggest benefit of the Passive house approach may be the trickle down effect resulting in, for instance, the Pretty Good House approach.
Response to Robert Swinburne
Robert,
As someone who has been living in a home with a single-point heat source since 1975, and as someone who remembers when David Hansen started installing heat-recovery ventilators in the 1980s, I agree with you that "we don't need a complex heating system" and "there are excellent ways to get fresh air without simply sucking air (and heat) out of the house with exhaust fans and relying on a leaky shell for makeup air."
However, these basic principles were well understood in the 1980s by builders in New England who focused on superinsulated houses -- long before Wolfgang Feist founded the Passivhaus Institut.
Response to Lloyd Alter
Lloyd,
I'm glad to hear that you have chosen to align yourself with those of us on the common-sense side of the barricades.
So -- will you be writing another blog to clarify the contradictions?
Incredible Article
The passive house is a great teaching tool. It teaches the limits of what's possible. It also teaches what make the most sense for the average home owner and business. The greatest and easiet is the air tightness goal that it sets. The rentals I own I use picture windows where I'm able. Under $200 each and perform better than most hung windows that cost thousands. It provides such an open feeling to the outdoors in zone 5/6. Air tightness makes a world of difference along with a continous air barrier. It takes more time, but not costly at all.
I wish schools would teach this, money management and other real skills. Maybe someday.
I'm in this camp
Count me in as one more GBA follower who is encouraged by your blog, Martin. I would only wish that you and the others purveying this approach would have called it "The Good House," as I think that these principles, used in an integrated way, offer a general path to achieve a good house (period). Or maybe, in a nod to 4. Northern Lighting, a path to a "Pretty, Good House." I am happy when the design and building science conversations continue to explore and discuss the integrated nature of design, comfort, energy use, longevity, operation, and resilience. It is important that our community be willing to think critically about our own activities and remember to see the forest for the trees. Thank you Martin, for so often reminding us of this, and for doing so by using history, context, and eloquence.
Response to Martin
Wolfgang does make it clear that he is standing on the backs of many before him and has only taken things to the next level - and brought many other people in to help. I do credit him with the excellent marketing skills to bring these things to a larger audience than was reached with "Mother Earth News". (which I grew up reading and I still have a pile of the solar home type books from the 70's and 80's) Passive House has made it easier for us small time architects and builders to convince clients of the importance of air sealing, insulation and air exchange because they've read a "New York Times" article on Passive Houses for instance.
If I get to do a full on Passive House, one of the primary benefits will be the marketing potential for my business.
You talkin' to me?
Martin,
So much of your blog resonated with me that I felt like it was an open letter to me. A couple thoughts come to mind. I liked the point you made about tri-pane windows being chosen over PVs. Maybe because it allows comfort to sometimes rule the day over economic optimization. Unfortunately, comfort can be very costly. I mostly like the pretty good house concept, but in my case I know going beyond the PGH concept to get to a desired comfort level in a couple areas will cost me big. One such area is window choice. As long as a person knows this going in, I see nothing wrong with it.
I hear your point about not knowing what someone will want to live in 200 years from now. My house is only just over 60 years old and seems largely inadequate from an energy use standpoint. But you also mentioned that buildings are being demolished at a fast clip in the U.S. I recently read (maybe on the GBA site) that 90% of the homes we will live in 50 years from now have already been built today. I don't know about that, but I can say that where I live 90% of the homes are AT LEAST 50 years old and sadly most of them still have not been upgraded to even the energy code efficiency of today--and many readers of this site find code level efficiency still very inadequate.
Finally, I'm glad to hear I'm not the only person willing to closely track energy use. When we switched out our 60 year old life-supported oil boiler for a gas one last winter, I tracked daily gas use religiously. My wife was so ashamed when I asked a neighbor to take daily readings from our gas meter when we left for a holiday. But tell me how many heating degree days there have been in my neighborhood and I can tell you how much gas I've used and how much it will cost me. Yes, I am a nerd.
I think you are missing one point.
You did address the point somewhat but I think it needs to be absolutely clear.
Location Matters. A Pretty Good House should be in a Pretty Good Neighborhood. I ain't talking about HOAs, but rather things like walk scores, efficient street layout, availability of transit (and good transit times and frequency) etc... After all most people don't want to cross country ski 5 miles to the post office when it drops to 30 below.
Response to Donald Endsley
Donald,
I'm happy to concede that the ten points in my manifesto aren't a complete list of the features of a good house. Nor was my manifesto intended to be such a list. After all, it's hard to whittle down all the features of a good house to a ten-item list.
As you correctly guessed from the last sentence of my article -- the one about bicycling to work -- I agree with you: transportation issues matter, and location matters. Fortunately, most green advocates agree on this point, so it isn't particularly controversial. (That said, plenty of people who claim to build green homes manage to forget that location matters, so it's good to remind them.)
In the U.S., we demolish
In the U.S., we demolish buildings at a surprisingly fast clip. Nice homes often end up too close to a busy road, or in a neighborhood where no one wants to live. Since the majority of populated areas are near coastlines, Sea Level Rise will have all those OSB constructed homes turn to mush.
11. One thing we all forget or just leave out is maintenance of wood products and the short life of sealed windows. Constant maintenance and replacement will place the Carbon footprint over the top on these building materials. Wood like they used 500 years ago, does not exist, so STOP the comparisons with todays offerings. OSB is not TIMBER.
Reply to George Hawirko
George,
I'm a little unclear on which of my statements or comparisons you are urging me to stop. I have written many articles warning builders that OSB is inferior to solid boards or plywood, and that OSB doesn't react well to repeated cycles of wetting and drying.
The day after I wrote a long
The day after I wrote a long post saying the exact opposite, I have to admit that the Pretty Good House makes a whole lot of common sense, and is pretty much the approach I took in my recent renovation. And those critics of your position on windows are just wrong; Even the very best window is a very bad wall. Frame a view and be done with it.
In response to your comment below, I don't think there are barricades. There's lots of room for discussion and different views, I happen to really like the ideas of the Pretty Good House, we would all be a lot better if everyone did it.
It's not a war, it's just the difference between a pretty good house and a very good house.
Butt out
"Do we need a new certification agency to provide Pretty Good House plaques? Let me think for a moment.... Nah."
I've got a sweatshop all set up, cranking out uPVC plaques as we speak. Mind your own damn business.
Response to Dan Kolbert
Dan,
I'll buy one! As long as I don't have to submit any paperwork...
Thanks to all
Thank you to all who have contributed to this long-running discussion - culminating in this succinct and insightful call-to-arms. I would quibble with Lemma 5 and suggest "...not just for passive solar gains."
Lemma 7 - Are there drainwater heat recovery systems which will work in single storey dwellings ?
Mr Alter's comment (in #15) that "the very best window is a very bad wall" hides the deeper truth that "any sort of wall makes a completely rubbish window" Windows are needed for all sorts of reasons and the size of them can, with a good architect, combine desired views and modest area. I have seen stunning examples in mountainous coastal areas where the window is a 'letter-slot' at eye-level framing islands, horizon and enough sky to satisfy any Winslow Homer fan.
For Peter Hastings
"Are there drainwater heat recovery systems which will work in single storey dwellings ?"
https://ecodrain.ca/en/products/
https://ecodrain.ca/media/products/ecodrain-installation-manual.pdf
They're on about Revision 3 of the design.
I'm not exactly sure what it's performance specs are, as they do not appear on Natural Resources Canada's third-party tested apples-to-apples listing tested at a specified flow & water temp. I'm sure it's WAY better than nothing, but probably less than what a 55" long gravity-film type vertical heat exchanger delivers (which would be between 45-65% heat recovery under the standard temp & flow conditions depending on diameter.)
Could be better than 35% though, maybe even north of 40%, but you'd have to bug them for some test data, since they're apparently not participating in the NRCAN standard-test comparison game, since they own the entire market for horizontal heat exchangers at this point.
http://oee.nrcan.gc.ca/pml-lmp/index.cfm?language_langue=en&action=app.search-recherche&appliance=DWHR&attr=0
The only paperwork required
Is a Jackson.
South Facing Glass
Thanks, Martin. It's always a pleasure reading your blogs.
Regarding the pushback on south facing glass, the last BSI article from Lstiburek makes the same point.
http://www.buildingscience.com/documents/insights/bsi-081-zeroing-in/
"Here goes. Don’t bother with the passive solar. Your house will overheat in the winter. Yes, you heard that right. Even in Chicago. Are you listening Passive House? You should go with very, very low SHGC’s, around 0.2, in your glazing. If this sounds familiar to those of you who are as old as me it should. We were here in the late 1970’s when “mass and glass” took on “super-insulated”. Super-insulated won. And super-insulated won with lousy windows compared to what we have today. What are you folks thinking? Today’s “ultra-efficient” crushes the old “super-insulated” and you want to collect solar energy? Leave that to the PV."
overheating
Anyone have an opinion as to what constitutes overheating? My existing house has a long wall of southfacing windows that warm the entire downstairs in winter. It screws up the radiant heat, but if the space gets up to 77°, that's OK by me. I can take my sweater off. In summer, a big river birch in front of the windows shades them pretty well. If it gets too warm, we open the windows.
My new house will have a pretty big expanse of glass on the south side, in part because we want the light and also because we'll have a nice view. I'm willing to chance winter overheating. Of course, we're in Maine, where being too warm is a nice change.
Count me out
No charismatic leader to quote.
No cache so you can boast about your green cred at parties.
No claim to save the earth.
No rigid criteria to blame the shortcomings of your house on.
No certification or plaque - despite Dan Kolbert's hollow promises.
It sounds too much like a common sense approach thought up by reasonable adults for reasonable adults. I'm out.
A Pretty Good Manifesto
Martin,
... spreading non-sense, ludicrous, asininity, ... Have you ever considered doing charity work as the target in a no-holds-barred name calling contest?
Anyway, it's a pretty good Manifesto and it's a good lesson in common sense.
My observations:
1) (Point 4). It's natural to see PV in the picture. It works in every climate zone with varying effectiveness. It produces energy that is fungible. It's year-round. It's carbon beneficial and that's a low profile yet key element in the Manifesto (n'est pas?) In our neighborhood PV is not encouraged and our lot is non-optimal or I might have some panels now. But, there are other projects that produce similar benefits. Normally, I'd expect comparisons to be made to the best available technology. In our climate (Chicago, zone 5A - 6B) and at our house I've found reducing solar gain (in summer only) to be more impactful in $ and in carbon and without tax credits or "programs". My rough calculations show the cost of PV of $1,000 for saving 320 kwh/year would have to be cut in half again before performing as well. Should we stick with Point 4 regardless of the comparative economics?
2) (Point 5). Passive Solar. Mr. Chatum makes a good point. I completely missed it. I think I read in the missing parts as though it were written :" ... we need to size and orient our windows with an eye to comfort and delight (as well as to manage solar gain and shading)".
3) (Point 6). All-electric Homes. If the objective is to reduce carbon, an all electric house makes sense, given PV or WIND supply. However, if economics are still relevant, all energy sources are in the discussion. No one in our neighborhood is likely to shut off their natural gas just to go all electric.
4) Nicknames. Beware of nicknames like "Mr. Overhang". Too much opportunity for unfortunate miss-readings.
5) (Possible Point 11). Something Old, Something New.
We should address buildings of all types, not just new residential construction. With so many existing buildings, greater gains are often with projects at those buildings. Not only are older buildings less efficient, there are just so many of them.
The PH phenomenon is instructive but I wouldn't spend anything just for a certification. I do, however, respect those who seek such recognition and who celebrate it once achieved.
Another really good article
Another really good article by Martin. But I have a question about LED lights. Martin, you urge people to put LEDs in all our fixtures to save energy. And I too love LEDs. But doesn't this ignore the fact that LEDs really don't survive very long in enclosed fixtures? Cree doesn't guarantee their bulbs in enclosed fixtures, and I've found very few other manufacturers that do. LEDs produce very little heat, but they are also far more sensitive to heat than tungsten filaments. If you go to Home Depot, for example, and look at customer comments regarding Cree bulbs, you see a surprising number of disgruntled consumers. A typical comment is, "It worked great for two days, and then--nothing." Somebody really needs to do an article surveying the survivability of LED bulbs in enclosed fixtures. I really wish that Martin H. or one of your crack investigators would take this on. I hope someone will respond to this.
Response to Stephen Sheehy (Comment #31)
Stephen,
You have told us that your house has a long wall of south-facing glazing; that the solar heat gain on sunny winter days is appreciated; and that when necessary, any overheating is easily handled by opening the windows.
I'm concluding that you are happy with the amount of south-facing glazing in your house. If you are happy, all is well. You appear to be abiding by Gary Proskiw's recommendations -- that your south glazing should "meet the functional and aesthetic needs of the building.”
If you were still at the design stage, however, you might want to perform a more subtle analysis.
Let's say that your house now has 100 square feet of south-facing glazing. (We'll call that Option 1). At the design stage, you might consider another option -- say, one with only 50 square feet of south-facing glazing. (We'll call that Option 2).
A good modeling program might tell you that (depending on what type of glazing you specified) that Option 2 saves energy compared to Option 1. If that's true, you might consider Option 2 -- less glazing -- as long as your family wouldn't miss the summer sunshine that floods your house.
Then you might consider two other options: let's call them Option 1A and Option 2A. These options would be the same as the other two, only with upgraded glazing (maybe moving from double to triple glazing).
Perhaps with triple glazing, you are able to show that the option with lots of glass -- Option 1A -- saves a bit of energy on an annual basis compared to Option 2A (the one with less glazing area). If that's the case, you might want to use Gary Proskiw's method, and determine whether the energy savings associated with the additional windows is worth the cost of the extra windows (especially when compared to an investment in PV). You just might find that the extra 50 square feet of glazing aren't a great investment. Then you could decide what to do.
But -- if some of your family members have Seasonal Affect Disorder, or you like to grow banana trees, this analysis doesn't matter. You may want to maximize the amount of south-facing glazing in your house, just because it brings your family delight. If that's the case, go for it -- because that's what matters.
Response to C.B. (Comment #32)
C.B.,
For a discussion of the advantages and disadvantages of PV trackers, you might want to look at the comments posted on my article from last week (A New Ground-Mounted Solar Array).
In Comment #41 on that page, Derek Roff discussed his tracker. He wrote, "Downsides include greater cost and vastly greater maintenance/reliability concerns. Our experience includes lots of repair calls for the trackers. So far, all under warranty."
On Malcolm Taylor's lament (Comment #33)
Malcolm,
You complained, "No certification or plaque - despite Dan Kolbert's hollow promises."
As far as I understand, Dan's promises aren't hollow. Only the PVC plaques are hollow.
However, I think that Dan is considering an upgraded plaque for a small additional charge. It would still be PVC, but the hollow plaque will be foam-filled. Stay tuned for more details.
Response to W.D. (Comment #34)
W.D.,
I'm a little scared. I wrote a ten-point manifesto as a reaction against a rigid program with strict rules. Now I'm being asked to interpret my ten points, as if I have suggested newer, stricter rules.
In case I wasn't clear on this point: The best way to interpret my suggestions is with good old common sense. (It hasn't gone extinct yet, has it?)
In my article, I suggested that anyone (a) who had a house with an unshaded south-facing roof, and (b) who lived somewhere where the local utility offered net-metering contracts, should consider installing a PV array. Now you tell me that you live in a neighborhood that isn't favorable for PV, and that you have identified other, easier measures that save more energy for a smaller investment. So what should you do?
At the risk of stating the obvious, W.D., you should start with the measures that save more energy for a smaller investment.
I suggested that south-facing windows be planned so that they provide comfort and delight. You pointed out that we should consider solar gain and shading. I agree, of course. That's how we achieve comfort, isn't it? Otherwise, any unshaded south-facing windows could cause overheating, especially if they are large. And overheating isn't comfortable.
I agree that anyone with an existing cold-climate house that is heated by natural gas has a strong incentive to keep his current heating fuel -- especially if we're talking about a working-class family without savings. I understand that. (Again, I'm applying common sense.) But if a family is planning to build a new custom house, they have the luxury of considering different types of heating fuels. In that case, they should probably consider designing an all-electric house.
In your last point, you wanted to remind readers that upgrading existing buildings often makes more sense than building a new custom home. I certainly agree. That thought was expressed in the last three sentences of my article, where I wrote, "If you want to tread lightly on the planet, plan to live in a small house or apartment. Don’t waste energy. If you follow these simple rules, your lifestyle is probably already greener than that of your wealthy neighbor who just built a brand-new Passivhaus — especially if you bicycle to work."
Response to Gordon Taylor (Comment #35)
Gordon,
You're right that LEDs can overheat in enclosed fixtures. The word "lamp" can be ambiguous -- so when I wrote, "You can find an LED lamp for every application," it's possible that some readers misunderstood.
For readers who are used to lighting jargon, it might have been clearer if I had written, "You can find an LED luminaire for every application."
In any case, here's my point: if you are planning a new house, go to a good lighting showroom and ask about LED options.
If you are retrofitting an LED bulb in an existing fixture, on the other hand, be cautious. Installing an LED bulb into an existing enclosed fixture might not be appropriate.
Certifiable
Thanks for an interesting column. I am merely an interested layman with a sensitivity toward good construction. I have owned more homes than average, on (so far) three continents, so I have been exposed to quite a variety of building techniques and seen my fair share of mistakes.
I am reminded of various ISO certification schemes in industry where many businesses lost sight of customers and products in the drive to comply with some "standard". Many of them (both businesses and schemes) no longer exist. One has to wonder if there is any real relevance beyond some trickle-down effect once a practice is found to be either a "no-brainer" or conversely idiotic.
It sounds like the 200-year-old Dingle stone cottage is still standing and in use, so that's quite testament to local builders using indigenous materials. Pretty good bang for the buck. Passivehuas? I'm not at all certain. I don't think I've ever seen a "real" one - just read about them. What percentage of new-home construction would meet a similar standard? I go to Germany a few times a year but the new houses I see would be unlikely to meet the standard, I suspect. I often see huge houses built with huge budgets and all the latest tech but with so many show-off windows they may as well have skipped the insulation. Because efficient (in both energy use and construction costs) houses often look a bit poky, actually.
Response to Steve P
Steve,
Q. "What percentage of new-home construction would meet a similar standard?"
A. As far as I know, there are still fewer than 200 Passivhaus buildings in the U.S. -- so this type of building represents an inconsequential (far less that 1%) share of new construction in the U.S.
Q. "I go to Germany a few times a year but the new houses I see would be unlikely to meet the standard, I suspect."
A. While most regions of Germany haven't yet made the Passivhaus standard mandatory for new construction, the German building codes are ratcheting up, and are getting close in some regions. Austria may be even further ahead than Germany in this regard. According to Wolfgang Feist, "The EU has said that from 2020, the national governments in Europe are required to establish new construction standards [building codes] with energy performance levels that are as low as the Passivhaus standard."
EU standards
Thanks Martin. I'm currently involved on a small renovation in the UK and I must say I will be amazed if that EU country achieves anything similar to Canada's R2000 standards (which I built to in 1990) by 2020. Currently, levels of insulation are being upgraded, but only where they do not (much) affect building practices. So lofts (attics) get extra insulation depths but walls are the same as 25 years ago - sometimes uninsulated. Passivhaus-style structures exist, but which would never meet the standard even in this (southern UK) temperate climate. Thermal bridging and vapour control are ignored by most builders entirely. In other words, they change things that require few changes in traditional construction techniques, instead of doing the things that provide the best return on investment. No doubt this is partly due to the difficulty in changing trade practices.
When I think of my travels in Europe, with very high-quality Scandinavian homes (expensive heating) to southern European homes with little attention paid to energy use (Mediterranean climate) it is very difficult to see how such a "dictatorship" of standards could be written - let alone enforced. But if anyone could do it, it would be Austria (population 8 million - about that of metropolitan London).
EU Standards
If the standard is written based on energy performance then the various national governments within the EU will be able to tailor their own building codes to match local climate conditions. Those with a benign climate will need less energy for heating and cooling (and can use the allowed surplus for cooking and washing) while those with more challenging climates will oblige their citizens (via punitive fines) to eat raw food and smell a bit. It's all perfectly logical...
Response to Steve P, comment #43
And yet the per capita annual energy consumption of the Brits is way lower than that of the Germans. And lower than most of the rest Europe too. Go figure.
PGH = NZE?
Is it safe to say that "Pretty Good House" is synonymous with the DOE's "Net Zero Ready?" The principles seem the same. Plan for solar, minimize loads, and aim for a low, but not crazy extreme HERS ratings (40's is good enough before solar).
[edit: typo]
Pretty Good Post
Thanks for the kind mention, Martin. This is a great post and I can't disagree majorly with any of its 'rules of thumb.' PGH is essentially a good way to design and build homes in a cold climate. I find much to support and, based on the Passive House projects I visited in Maine, I see much more agreement and alignment between PGH and Passive House than is possibly acknowledged here.
It's inspiring to see how many GBA articles have been stimulated by or are referencing the NAPHN14 Conference. I saw great evidence of the alignment and overlaps between PGH and Passive House at NAPHN14. I also had the honor of learning about how PGH evolved and had fun meeting a few of its Maine proponents. (Thanks for the beer, Dan, and for the fantastic Haus Party, Steve.) It looks like the experience of this group of builders all gathering together to figure out exactly what is working for buildings in this region will help everyone build better buildings. I do have a sneaky suspicion that PGH builders will all end up building Passive House projects sooner or later though. (Once you hit 0.6ach, the rest gets pretty easy.) With the support, supplies and technical skills already available to you all in the North East, it looks like you just need a local window manufacturer to produce a well insulated frame with good IGU’s and you’re there? Then, for those odd projects that simply won’t fit into the ‘rule of thumb’ box, the PHPP can be used to help you figure out exactly what is needed to build a Pretty Good Passive House. (I’m doing exactly that for my projects here in California.)
Response to Dwight Harris (Comment #46)
Dwight,
Q. "Is it safe to say that Pretty Good House is synonymous with the DOE's Net Zero Ready? The principles seem the same."
A. I am not familiar with DOE's Net Zero Ready program, but it wouldn't surprise me if there were substantial overlap between the principles of that program and the ideas in my article. The basic idea behind Pretty Good House design is common sense. There is no list of rules, so the Pretty Good House concept is never going to align perfectly with any program that includes a list of rules.
I make no claim of originality. All of my ideas are borrowed. Hopefully, common sense is still common enough that it is widely distributed in the population, existing happily without authorship.
Response to Bronwyn Barry (Comment #47)
Bronwyn,
Thanks for your kind words. I suspect, however, that you give too much credence to the idea that Maine builders who complete a Pretty Good House have almost built a Passivhaus.
You wrote, "I do have a sneaking suspicion that PGH builders will all end up building Passive House projects sooner or later though. (Once you hit 0.6ach, the rest gets pretty easy.) With the support, supplies and technical skills already available to you all in the Northeast, it looks like you just need a local window manufacturer to produce a well insulated frame with good IGU’s and you’re there?"
That may be true in the areas of California where you work, but it isn't true in Maine. The Passivhaus projects that have been built so far in Maine differ in many substantial ways from the type of house I describe in this article: they end up with very high R-values in the foundation and roof; they usually require very expensive windows; they usually end up with very expensive ventilation systems; and they usually require the assistance of a fairly expensive Passivhaus consultant.
Finally, the idea of comparing the kWh savings of a proposed energy improvement with the kWh savings that would come from a PV system of the same cost is totally foreign to the Passivhaus method. When I have suggested this approach to Passivhaus designers, my suggestion has been met with hostility and derision.
R 5 Windows
Just curious what you might suggest Martin and others for R 5 windows.
I'm a builder in New Brunswick Canada, who has built both PGH (before it had it's name) and Passive House both have their Merritt and can be cost effective immediately for the client, But from my current experience our clients like that their is some sort of target or 3rd party verification if desired. Anyway not the point of my post. I was curious to learn from the GBA people what windows they are using in a PGH scenario?
In my case on two PGH projects we have used JeldWen Casement vynal Tripple Glazed with Cardinal glass with 2 coats of the 180 low e. The glass does a good job with keeping the comfort level up and condensation away however in the house without a forced air heating system (they use point source heat both a wood stove and minisplits)we are having problems with the frames condensating when the weather get's really cold.
Other than that the PGH are preforming better than modeled and the clients are super happy!
On our passive House projects we have used UPVC Internorm ThermoPassiv and UPVC Klearwall and have not had these issues. (both of which were very well priced for the performance and quality if you are aiming to certify a PH)
Just wondering if i'm missing a option for the PGH windows where we wont have these window sweating problems without a heating vent below each window?
Keep up the good work Martin!
response to Tim, re PGH windows
My PGH is in the framing stage (or was until we had several inches of heavy wet snow yesterday.) We are using UPVC Intus triple pane windows, PH certified. I'll report later on how they perform. For whatever it may mean, they are insanely heavy and seem well put together.
What about existing houses?
Great post!
For new homes, PGH is a great idea, a happy middle of sorts. Passive House is pretty tough here in the cold north, PGH isn't. (Sorry, Bronwyn. =)
What about the 100 million or so existing homes, though? Can we have a PGH type idea for them? Maybe a range of kwh/sf or something like that?
Some shell tightening can make heat pumps work in most average sized homes, and go all electric (which I'm a BIG fan of), and the furnace needs to get replaced at some point anyway, so why not?
Fixing 1 million new homes/year still only pulls off 1% of the job at hand... and good luck finding an insulation contractor that can pull it off, how can we get more for them and some good training, too?
pretty good wedge?
Hi Martin, I love how you make us Passive House types think hard about things we may not see due to "zealotry blinders." I know I went all in when I learned about PH, and, like PHIUS, have grown more circumspect over the past few years. And although I wholeheartedly agree with most of your points, I think it unnecessarily sets PH designers and builders against PG designers and builders.
The thing is, most houses are not designed with architects and energy consultants. We really need good rules of thumb for those who want to do more than "barely legal." I'm lucky to design houses for people who want Pretty Good and Really Good houses, and I'm grateful to have a tool that lets me understand the implication of my design decisions. Yeah, long discussions about THERM and the like make my eyes glaze over too--what I really want is to design buildings that people love to be in, that somehow make their site or neighborhood a better place. And it's true that I could go 5-10-20-40 and get a Good house, but my clients expect more than Pretty Good. So don't make guys and gals like me seem like freaky zealots!
The other thing I"m grateful for is the building science discussion that PH brought to the field. I fell in love with architecture in 1979, heyday of Passive Solar and Superinsulation (thanks for that history PDF BTW!), but when I got into offices in the early '90's, no one was talking about that stuff. It wasn't Pretty Good, it was Really Big mostly. So when PH came over, PHIUS included building science training (that's where I learned of Lstiburek's Builder's Guide). I know a lot of you guys were at it all along, but sadly that conversation wasn't thriving in the field of architecture. It's getting better, but slowly.
Anyway--thanks again for your continued insistence on humility, common sense, and for the idea of doing widespread good things instead of occasional incredible things.
Followup to #45 EU Standards by James Morgan
"...the per capita annual energy consumption of the Brits is way lower than that of the Germans. And lower than most of the rest Europe too. "
No doubt there are many factors, but the first I would consider is that UK homes are among the smallest in the EU. The population is also very urban - my expectation would be that city-center apartment blocks and "terraced" (attached) homes are more energy-efficient ignoring other factors.
http://shrinkthatfootprint.com/wp-content/uploads/2013/04/Percapitaft22.gif
http://shrinkthatfootprint.com/wp-content/uploads/2013/04/housesizeft21.gif
SHGC
There was discussion already in the comments about overhangs in context of your point #5 not to worry about passive solar heat gain. I would think that the solar heat gain coefficient (SHGC) of the South facing windows should still be a consideration too. Choosing high SHGC glazing costs the same as low SHGC glazing, yet provides free heat in the winter, and properly sized overhang blocks most of the heat gain in the summer. In my experience in a VT passive solar, super insulated house, overheating due to solar heat gain in the winter isn't an issue. On very rare occasions it may overheat a bit in the Fall when the sun is starting to get low in the sky and the outdoor temp can still be relatively warm. However, that is very easily controlled by simply opening a window. It seems to me that there's a case to make that the amount of South facing glazing isn't super critical. However, the passive solar design principles of proper overhangs and high SHGC windows are still very much worth consideration for the windows that are installed.
Response to Tom Bassett-Dilley (Comment #53)
Tom,
If a client wants a Passivhaus, and can afford one, by all means you should meet your client's expectations. Especially in a mild climate (like much of California), achieving the Passivhaus standard is relatively easy (compared to the hoops you have to jump through in a very cold climate).
For anyone who is thinking about a Passivhaus, the bottom line is: know what you are getting into, and make an open-eyed decision with full knowledge of the alternative paths available to you.
Response to Daniel Beideck (Comment #55)
Daniel,
I agree with your point about the SHGC of south-facing glazing (especially in cold climates). In fact, I wrote an entire article on the topic back in 2009: High-Solar-Gain Glazing.
Reply to Daniel Beideck
Open a window! What kind of apostasy is that? It's those kind of suggestions that set back the green building movement. I've sent a link to the PH institute for further denunciation. Sheer recklessness!
Reply to Martin (comment 56)
Martin, overall I just love what you said about pretty good houses. I agree wholeheartedly and think that is the direction builders should move in. I have to correct a misconception about California's climate though. It is easier to build a house to PH standards here in California than in climates like yours, but it is less cost effective here even than in yours. One of my biggest pet peeves about the PH standard is that it just doesn't make economical sense here, or in high desert regions elsewhere.
Typically in these kinds of climates there are extremes of temperatures between daytime and nighttime. Sometimes as much as 50 degrees. The important point is that there is a lot of sun during the daytime and the temperature will reach into comfortable temperatures for humans at some short time duration during the day in winter. The same thing happens at night in summer. Using an HRV in a climate like this is ridiculous. It's a complete waste of energy to plumb and force air through a restrictive air exchange device in this climate. It makes much more sense to grab outside air during those times of the day or night when temperatures are comfortable to humans and bring it inside. The only requirement is a large automated unrestricted fan that operates a few hours per day and enough insulation in the house to maintain a comfortable temperature for the 24 hour period for the cycle to repeat.
This is not a hard idea but it is a "different" one from the paradigm PH promotes. It also requires a backup heating device in winter and probably ceiling fans for summer. It is climate specific and makes much more sense than what PH is promoting here in California.
Edit: I should add that this isn't just a quirky idea. It should be possible to use the same idea in hotter or colder climates during the shoulder months to eliminate heating and cooling plug loads during those months. It would have the restriction that it is not extremely humid outside during the hours that outside air is being pulled in. As long as you have a backup heating or cooling system, because you can't predict the weather, it should be able to save substantial conditioning plug loads in many different climates in varying parts of the year.
cost effectiveness
A few years back in one of these long comment sections to one of Martin's harangues of PH sensibility (or perceived lack thereof), he suggested using BeOpt (a program from NREL) to analyze the cost effectiveness of PH, like whether those 14" of XPS under the slab are really a good idea. PHIUS just got done doing just that, using a 2,000s.f. house modeled through 110 N. American climate zones, and they are about to propose updating the standard to align with climate-specific and US construction-specific expectations. It was a fascinating study, and even here in Chicago we see a relaxation of that Annual Energy Demand which led to diminishing-return insulation levels and too much south glazing. It's still a very high bar, but it accommodates PV where it is more cost-effective than insulation, so it's closer to the DOE ZNEH program.
Who needs a south facing window facing a neighbor?
Our front (east) with Bay window and back (west) Patio doors for yard view are the best with all my natural landscape in the middle of our city. Two smaller windows serve the light needed as far as the south wall. What was needed was heat here near Green Bay, WI and two Solar Sheets look nicer than two more expensive windows. They give us heat only when needed and their reflective heat in summer help grow HUGE pepper plants and beans so high you can't see the solar sheets behind them. Windows? Hah!
Response to Eric Habegger (Comment #59)
Eric,
You're right: while it is less expensive to build a house that meets the Passivhaus standard in a mild climate than in a very cold climate, the cost of the upgrades needed to reach Passivhaus don't make economic sense. This stark fact only becomes starker during historical periods when energy prices are dropping, as they are now.
Response to Tom Bassett-Dilley (Comment #60)
Tom,
You're right: I have been trumpeting the usefulness of the BeOpt approach to energy analysis ever since I wrote my first article (for Energy Design Update) on the BeOpt program back in September 2006.
PHIUS's decision to use BeOpt to gain insights into envelope standards for different North American climate zones is part of PHIUS's plan to develop new Passive House standards for North America.
GBA has been reporting on these efforts for a long time; our articles on the topic include one by Katrin Klingenberg (New Passive Building Standards for North America) and a September 2014 report by Allison Bailes on the status of the recommendations of the committee looking into these new standards (Highlights from the North American Passive House Conference).
The logical rigor of Graham Wright's approach to using the BeOpt results is undermined by the decision of the PHIUS committee to "go beyond" cost-effective solutions. As Bailes wrote, "The goal of that work is to find the real optimum in cost-effectiveness. And then go beyond it. Wright's reason for going beyond the optimum was, 'Because that’s our schtick.' I'm not sure how much sense it makes to find the minimum and then go beyond it, but hey, that's what the upcoming member comment period is for, I guess."
Response to Paul Kuenn (Comment #61)
Paul,
I'm not sure what you mean by "Solar Sheets" -- I'm guessing that it is a brand name for a solar air collector or some type of PV module -- but I'm glad that the product is working for you.
You're right, of course, that window sizing decisions have to be based on common sense. If your neighbor's house to the south is very close, you don't want the loss of privacy that would come from large south-facing windows.
Less is more
Yes Martin, a Canadian born solar air collector with a very nice frame. Keeps the house at 65-67 when it's below 0F so the heat doesn't need to come on. Nothing lost when it's cloudy for 45 days in a row. I do love visiting south facing homes with a view but can feel the cold at night even when their expensive triple pane windows seemed to have promised more. I'd rather have the heat only when and where needed. I certainly wouldn't want neighbors to think we're watching them either. That's city living.
Keep the stories coming, they're great!
Souless
PGH. Oi Vai. Talk about something that needs a name change! The name in and of itself tears at the soul of quality. Come on.
As far as the PH v PGH v PHI v PHIUS v man v himself v GBA goes; I will relay this one thought before I return to my far better than pretty good day.......
Robert Pirsig stated this well enough and it directly applies to this conversation
"I would like not to cut any new channels of consciousness but simply dig deeper into old ones that have become silted in with the debris of thoughts grown stale and platitudes too often repeated. "What's new?" is an interesting and broadening eternal question, but one which, if pursued exclusively, results only in an endless parade of trivia and fashion, the silt of tomorrow. I would like, instead, to be concerned with the question "What is best?," a question which cuts deeply rather than broadly, a question whose answers tend to move the silt downstream. There are eras of human history in which the channels of thought have been too deeply cut and no change was possible, and nothing new ever happened, and "best" was a matter of dogma, but that is not the situation now. Now the stream of our common consciousness seems to be obliterating its own banks, losing its central direction and purpose, flooding the lowlands, disconnecting and isolating the highlands and to no particular purpose other than the wasteful fulfillment of its own internal momentum. Some channel deepening seems called for."
Thank's Martin, for a real good time!
Response to Christian Corson
Christian,
Like you, I revere quality. I also feel that it's essential to keep a sense of humor -- and a sense of humor is one of the strong threads that runs through the "Pretty Good House" movement. In fact, this sense of humor is evident even in the chosen name.
I'm sorry if the chosen name of the "Pretty Good House" movement tears your soul asunder. (Speaking of souls, who is the "soulless" person you refer to in your title?)
I'm glad that your day is going well, and I appreciate your Pirsig quote. Like Pirsig, I believe in the pursuit of quality -- as well as the reexamination of the deep ruts that residential construction finds itself bogged down in.
Honkin' spot on!
Martin: I'm here in my office with a rope tied to the ceiling and a noose on the other end. This week alone, just at Wednesday; I've had multiple calls regarding basic moisture issues in homes.
Even though there are many very good building programs out there, I'm still convinced that the word "PRACTICAL" must no longer be in the dictionary. My message has always been: don't do anything "CORNBALL" and make sure we are actually doing right for the long haul.
Your article about the real value of a home that could last 200 years is honkin' spot on!
These may turn out to be homes with no societal value at that time but have burned up a boatload of resources to get there.
I'm even uncomfortable buying light bulbs that last 20 years. I don't really want to be 'locked in' to anything for that period of time -- not even a good shirt.
Things change and I change. My values need to be flexible enough to adjust to current conditions as they are.
If we in the Building Community are that good at predicting the future, we're in the wrong business in the first place. We could make more money at a carnival with a crystal ball.
I'm back on 'regular' caffeinated coffee so this message may be slightly "charged" up.
I think Einstein said it best: see the attached image from a book entitled "Leading with Passion."
.
Pretty Good House
As usual, Martin has brought focus to a subject that has seen far too much bickering over very fine points. I'm referring to the PH debate and whether it should be the be-all, end all for home performance. Let me add some thoughts from the perspective a former utility program manager/research who has been following the PH discussion from its introduction in the USA ( I worked for SMUD for 22 years as a new construction program manager and researcher).
First, let's give PH it's due. It helped establish some basic performance standards, primarily for house built in cold northern climates, and brought scientific rigor to a profession/business that mostly ignores measurement and quality control. However, implementation of PH is impractical on a large scale and impossible to achieve for the millions of existing homes the vast majority of Americans (and Europeans) live in.
So given that it's impractical and uneconomical for wide spread adoption of PH in the building industry, what is the alternative? This was the issue I had to address day-to-day during my utility career In particular, how are we going to achieve the significant energy savings needed to address a host of problems - climate change. market transformation, etc. My experience as a utility program manager showed me that you could build incredible performing new homes or upgrade existing homes - zero energy - if you were willing to pay the price. And let's be frank, given current utility prices these homes don't make economic sense. Arguments about comfort and durability although appealing don't make up for dollar savings, either. We all know that people will adjust or make adjustments to find their "comfort level" and rarely think about the maintenance of their home. There's also those pesky plug loads which are best addressed through standards such as California's Title 20 standards.
So what's to be done?
My research showed me that Pretty Good Homes (PGH) are the answer for the existing home market, the most important and by far the biggest source of the large scale energy savings we need if we want to make a difference in the residential sector. In particular, PGHs that focus on getting the basics right - air tightness, adequate insulation, and excellent HVAC and water heating - can be the vehicle for transforming the residential building sector.
PHGs does this by addressing several critical areas.
First, they provide verifiable, persistent real savings to both consumers/homeowners and utilities and their regulators. Note: don't under estimate the importance of energy savings, especially demand savings to utilities and their regulators. Let's be frank. Utility efficiency programs drive home performance as evidenced by the billions they have invested in home performance over the past few years. It's especially important to utility regulators that these programs provide verifiable, persistent, and cost effective savings to justify rate-payer funded programs. PH is not cost effective from a utility or rate payer perspective. PH advocates downplay this important issue.
Second, it can create a market for home performance that supports home performance contractors. In fact, PGHs could lead to transformation of that market as consumers become aware of PGHs benefits creating market demand that leads contractors to change their business practices, including motivating new home builders to change their business practices in response to wide spread adoption of PGHs in the existing home market.
Third, PGH "standards" can be adapted for any climate with minimum differences making it easier for consumers and contractor to understand. The basic differences in climate specific PGHs would be in the amount of insulation required; everyone would know that you need to meet minimum ACH values and put in "minimum" performing equipment - e.g., 90+ AFUE furnace, .80 EF water heaters, etc.
PGHs could also provide other benefits primarily at making the home performance contracting business easier and reducing confusion in consumers' minds about the value of energy saving upgrades to their homes.
PH has a role to play but it will primarily be as "how far can we push this" research role. As such, it will never have see wide spread adoption. PGHs, on the other hand, could see wide acceptance by consumers and contractors especially if supported by utility home performance programs.
Response to Michael Keesee
Michael,
I'm glad to chalk up another endorsement of the "Pretty Good House" proposal.
This is a good time to remind GBA readers that the originator of the "Pretty Good House" is Dan Kolbert of Portland, Maine. So, I tip my hat to Dan.
Here is a link to the first GBA article on the topic: The Pretty Good House.
humility and healthy buildings
Martin, thanks for this. I would add a corollary to your rule #1: given the toxicity of our built environment, we would do well to give more consideration to the health implications of the materials we use.
Acknowledging past mistakes and future uncertainty to me means paying much more attention to the toxicity of building materials, so that the next generation of contractors doesn't have to work around or through long list of occupational hazards like asbestos, fiberglass, lead, formaldehyde, pcbs, flame retardants etc. and so that future occupants don't have to worry about the health implications of making improvements to buildings.
As with energy, the notion of avoided cost is at the heart of this argument: it's much cheaper to design and build out the cost in the beginning than to pay endlessly on the back end.
Norm, you've hit the nail on the head here. Thank you. Some of us don't wait until the scientists, researchers, and marketers confirm (or don't) what any sane level-headed man, woman, or child understands without input from "professionals" - a poison is a poison is a poison, if not to the occupant of the house than to some other party involved in the process of manifesting the poison and making it available for "consumption". For instance, just because polyethylene aka petroleum is considered by some professionals to be far less toxic than other poisonous building materials to building occupants if not to multiple other parties involved in its unearthing, processing, transporting, and landfilling, it somehow gets a free pass in the PGH process.
Here's one taste of Another Way: https://foursevenfive.com/blog/a-passiveagrarian-homestead/
Polyethylene?
I understand we're taking apples and oranges, Martin. No worries there. I'll keep offering up apples periodically, and you'll talk about the apples as if they're oranges. All good.
My point, which consistently is ignored, is that the production processes of and around petroleum - among many other aspects of petroleum handling, selling, design, "consumption", landfilling, oceanfilling, et cetera - are problematic to the point that utilizing petroleum specifically and other fossils such as mined coal and "natural gas" on ANY LEVEL drives demand for it. The sheer utilization of petroleum on any industrial level must end if "climate change" and other catastrophes perpetrated by certain men and women is to end. The act of fractional distillation of petroleum itself is at issue in my posts.
And of course polyethylene is not going to kill the person handling it in his or her home. It may give off free radicals that compromise fertility and other systems of human vitality, but it won't kill anyone by its presence. We agree on that point, and there's no point in acting as if we disagree on it. If you're ever ready to go deeper on this point, I'd be thrilled. No worries if not! Keep up the great overall productivity if it pleases you.
Sometimes scientists (chemists in this case) provide info the 'sane level headed folk' need to make their sane level headed decisions.
That something is made of oil doesn't automatically grant it toxic status. CO is comprised of the same components as my breath but is severely more toxic. Chlorine is quite toxic on its own, but is necessary for human survival (and tasty) when paired with sodium.
Did our sane-level-headed grandparents intuit that lead was so toxic?
It is undoubtedly possible there are substances we work with that are more toxic than we currently know. Our scientific understanding has grown since the days of heavy lead use, though.
To be fair, so too has our ability to create altered compounds. I'm not against some healthy skepticism. But we need some basis to work with. If one is using the baseline of 'natural = good' and visa-versa, it might be worth remembering that oil is natural, as is lead, asbestos, (list goes on).
We all have biases though. If someone were to tell me wood was somehow toxic, I'd have to ignore them. I put that stuff in my oatmeal for breakfast and breath a heavy line of it for lunch. Smells like purity and heaven.
Gregg,
There are at least two different approaches to determining toxicity: (1) Going with your gut ("It's manufactured from petroleum") or (2) Looking at the data and listening to scientists. You can go with Approach #1 if you want, but I'm sticking with Approach #2.
Polyethylene is used to make milk jugs. Moreover, if a house has polyethylene between the drywall and the studs, it's unlikely that I'm going to lick it or swallow it.
If you go with your instincts, you might think that natural materials are safer than materials made from petroleum. Asbestos is natural -- it's a rock -- and lead is an elemental metal. Wealthy Romans used lead vessels for their wine goblets, and many of them probably ended up with lead poisoning. Polyethylene would have been preferable.
Greg,
I admire your desire to do the right thing and to think deeply on matters.
Concerning this: "My point, which consistently is ignored..."
Your point wasn't that clear. Perhaps you were juggling a multitude of fruit and it was tough to focus on the apple you were hoping would stand out.
It sounded as if you were claiming that PE was, itself, toxic.
"utilizing petroleum... on ANY LEVEL drives demand for it"
Yes. But how do all the materials we build with (even if not petroleum based) get processed and transported?
You may have avoided use of PE, but we cannot altogether escape use of oil in our current reality. Don't get me wrong, you should build how you want (and from a quick glance it looks like a great project).
The big picture of breaking free of oil is about problem solving and systems thinking, not tying arbitrary knots around myopic thoughts. (I'm guilty of it though, as probably most of us are)
Response to Norm Farwell
Norm,
I agree that it's important to pay attention to toxicity. But labeling a material "toxic" should only be done after researchers have assembled enough data to support the toxic label.
As your examples show, a natural mineral like asbestos, which is mined from the earth, or a simple element like lead, can easily be toxic -- while plastics like polyethylene are far less toxic than asbestos and lead. That makes some of the knee-jerk reactions of some green builders suspect. Once we have the data, we can move forward and eliminate toxins.
passive solar
I am a plant collector and have always dealt with the question of balancing energy concerns with having lots of light. Slowly I've learned to incorporate experience with solar greenhouse design into the building I live in.I was there for the 70's and know what passion can go with passive solar. I would say that the principles are so seldom applied correctly that general advice toward moderation is wise. Still, for those with the desire to experiment, there is no reason not to. I still may end up just living in a solar greenhouse.
Response to Brian Carter
Brian,
Every family is different. If you are a plant collector, it is possible that nothing in life will give you more pleasure than living in a greenhouse.
R-5 Windows
In the good old days (1980s) before the advent of most triple glazed, R-5, window options, your authentic passive house employed thermal shutters over the glass to receive the blessings of solar gain in the daytime and insulation from the cold at night. The late (great) William Shurcliff put out a wonderful book, "Thermal Shutters & Shades," that provided much inspiration (and whimsy) on the topic. The thermal shutter option seems to have slipped away from the pretty good house or Passive House debate, perhaps because shutters required diligent action on the part of the home owner to employ ("passive houses for active people" used to be the mantra!) Great column, Martin!
Response to Carl Mezoff
Carl,
Thanks for reminding us about passive solar house recommendations of the 1970s and 1980s. Looking back at Shurcliff's book (see images below) brings back memories -- his references to the 1977 "Toward Tomorrow Fair" in Amherst, Mass., and Kalwall plastic glazing, make those days seem a long ways off.
Few homeowners want to walk around the house every night before they go to bed, and fasten all of their thermal shutters in place -- only to have to open them all up in the morning before they drive the kids to school or head off to work. (Moreover, few homeowners these days would appreciate the look of the taped-on hinge detail that Shurcliff explains in his book -- shown in the second image below.) Triple glazing makes more sense.
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GREAT JOB!
Fantastic article Martin. Please put me down as advocate for the pgh club.
Your swing at passive solar may have been too mild. And passive solar overheat isn't necessarily a bigger summer overheat problem. I think its an all the time control problem with very dubious benefits.
Winter overheat is not solved simply by opening windows. Upstate NY gets plenty of days over 50 in winter, too much solar load means air conditioning. Passive solar is too risky in my book. #4, the Posluszny example hammers this home - alternatives offer greater benefits with homes that aren't pigs.
#10: My experience if you fix crappy houses and make occupants comfortable the behavior opportunity shrinks to the point you shouldn't spend much time fretting about it.
PV
If you don't have a good south-facing roof or trees shading your south-facing roof, you should consider:
http://gmisolar.com/solar-panel-tracking-systems-pole-mounted-solar/
I am currently putting one in at my house. A solar PV array on a steel pole with the dual-axis rotation to follow the sun will maximize the electrical power generation. While the size of the array is more than is needed for lighting/heating/cooling the house, its output is also planned to provide power to fully-electric (ex. Ford Focus Electric) or plug-in hybrid electric (ex. Ford C-Max Energi) vehicles. The goal is not just be a carbon-free house but a carbon-free household.
I suggested lets do a "pretty good house" to some clients the other day. Somehow I didnt appeal to them! ... and a lengthy instructional context explanation..well you can imagine how that would go. One friend suggested Pretty Damn Good House...that seems to work better. Stealth PH would probably cause some legal problems with PH...does anyone have any sound byte friendly alternatives to the pretty good house identifier?
This is so sensible! I keep telling people we should aim for a Net-50(% reduction) house, or even a Net-25 house. If we get too focused on the very very best, we forget that there are shocking numbers of homes out there with no attic insulation, or even the very basics. I like making energy efficiency affordable and attainable for everyone, not just people with unlimited budgets.
Jacqui,
The houses that have come out of using the approach seem to function very well. One was featured in a recent blog: https://www.greenbuildingadvisor.com/article/a-pretty-good-house-in-the-sierra-nevada
I believe the main photo is problematic.
John, I've had that thought once before as well.
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