Hermetically-sealed boxes (beer coolers)
Should we avoid airtightness?
Should we avoid “superinsulation”?
How tight is too airtight?
Is 2 ACH50 too tight?
what about 1.5 ACH50?
Should we blower door test as we go along to make sure that we have not crossed the “insanity line” and created a hermetically-sealed box?
If a certain degree of “leakiness” is desireable… where SHOULD our enclosures leak?
Where should our enclosures NOT leak?
How much insulation is too much?
If I lived in the backwoods of Vermont I could guess what the “appropriate” values might be by backwards engineering a Riversong House.
I live in North Texas so I just don’t know what my goals and LIMITS should be.
Yes, my tongue is touching my cheek…
But I am also serious about these questions.
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Replies
John,
Q. "Should we avoid airtightness?"
A. No.
Q. "Should we avoid superinsulation?"
A. No.
Q. "How tight is too airtight?"
A. As long as a house is equipped with operable windows and a mechanical ventilation system, there is no such thing as "too airtight."
Q. "Is 2 ACH50 too tight?"
A. No.
Q. "What about 1.5 ACH50?"
A. No.
Q. "Should we blower door test as we go along to make sure that we have not crossed the "insanity line" and created a hermetically-sealed box?"
A. We should definitely blower door test, but I don't understand what you mean by the "insanity line."
Q. If a certain degree of "leakiness" is desireable... "
A. It's not.
Q. "...Where SHOULD our enclosures leak?"
A. We should do our best to ensure they don't.
Q. "Where should our enclosures NOT leak?"
A. At seams and intersections between different materials and building assemblies.
Q. "How much insulation is too much?"
A. If the energy likely to be saved over 50 years exceeds the embodied energy of the insulation material, then you've probably installed too much insulation.
John
I have to admit that I really don't understand the concern for enclosures that are too tight. Mechanical ventilation is required, so what is the problem? When the HRV or ERV is working properly, we are getting plenty of fresh air at a reduced energy penalty. If the power goes out, you simply crack open a couple of windows. Over 6000 Passivehaus homes have been built to date, and no one seems to be complaining about air quality.
The biggest resistance for air sealing seems to come from builders, who find the required detailing to be too onerous and time consuming. The customer has to be prepared to pay for the extra time invovled.
The energy saved by making new homes more airtight should pay for the extra air sealing measures.
My quick calculation for a 2,000 sf house in a 7000 hdd climate shows 200 therms used due to infiltration with the air change at 7 ACH50, the 2009 IECC standard. Moving to the 3 ACH50 standard in the 2012 IECC the infiltration heat loss is 85 therms, a 115 therm savings. Cheap natural gas slows the payback some but if you are heating with electricity, fuel oil or propane, the ROI on building more airtight should be substantial.
Martin,
the vague "Insanity-level" comment was a friendly jab at Robert
John,
Are your questions related to a concern that there is a point of diminishing returns on cost or effort?
Are you concerned that the quest for the lowest possible ACH number motivates people to choose construction materials that may or may not be sustainable en-masse?
John,
I can't tell if you are playing the role of agent provocateur or if you are genuinely concerned that builders in the U.S. are making new homes "too airtight."
Martin,
I am challenging Robert
I do not myself see what is wrong with airtightness
I think air control is better that out-of-control
John,
Agent provocateur it is, then.
Lucas,
I think we need to search for SIMPLE and Cheap methods for achieving VERY GOOD Airtightness
John
To your SIMPLE and CHEAP requirements, we should add DURABLE, INSPECTABLE, and REPAIRABLE.
John,
I too have wondered these things as well. I have much respect for Robert R, and some of his posts have made me question my "houses can never be too tight" thinking.
I do believe that as long as you have operable windows throughout the house, an uber tight home is not a problem.
I do, however, think that a home completely encapsulated with a !@#$-load of foam (beer cooler) IS a problem. Though I have no scientific data to back this up, gut-feeling tells me that a plastic bubble is probably not the greatest type of shelter for human beings. Not to mention the environmental impact of using a !@#$-load of foam.
It is possible to achieve a super tight, super insulated building without full cavity spray foam in wall and roof assemblies. This is where I hope the green building movement is heading.
Brett & Garth,
I agree completely with your comments.
Including respect for Robert
For most climates, 12 inch thick walls filled with cellulose will suffice to provide a super insulated wall. In very cold climates however, these same walls must become at least 16 inches thick or more, resulting in tunnels for window and door openings. Don't know if I can live with that...still pondering the options.
OK, now that you're being nice, I can jump in (actually, I just noticed the thread - thanks John for starting trouble).
A leaky 2-storey, 2000SF house typically moves 9 or more ACH50. An ordinary new house (according to surveys) moves 5.63 ACH50, which equates to approximately 0.38 ACHnat (natural) in a northern clime. Of 3600 homes blower door tested for Efficiency Vermont (the state's conservation utility and Energy Star agency), 73% moved less than 0.35 ACHnat - which is what the ASHRAE standard for indoor air quality used to be. In other words, most new homes are too tight for good reliable indoor air quality and would require 186 therms to heat incoming air in a 7,000 HDD climate. Of those 3600 homes, 69% met the HERS target of ≤5 ACH50.
Tightening them up to 3 ACH50 (0.15 ACHnat) would reduce ventilation make-up heat to 73 therms, and would bring them to the default assumption for ASHRAE standards (2 cfm/100 ft² for infiltration, which is the equivalent of 0.15 ACHnat with 8' ceilings) and so would require mechanical ventilation at ASHRAE rates and the consequent energy consumption – both for the fans and for the make-up heat (unless partially recovered with an HRV). The difference in heating load between the standard house and the tighter house, with ventilation at 0.225 ACH (60 CFM continuous) as required for indoor air quality would be 119 therms.
Tightening that house down to 2 ACH50 (0.10 ACHnat) would further reduce the heat load from natural air exchange to 49 therms, but additional mechanical ventilation would be required to meet minimum ASHRAE standards, so there would be no additional energy savings (again, unless the additional air could have its heat scavenged).
Further tightening to 1 ACH50 (0.05 ACHnat) would require a further increase in fan flow volume and no net savings.
The US DOE Build America Program requires 2-3 ACH50 and the more severe Canadian standard is 1.5 ACH50 (while Sweden requires 0.5 ACH50).
My standard is 2 ACH50 (0.10 ACHnat), which is more than twice as tight as typical new homes and still allows some minimal natural air exchange when the power is out and nobody wants to open windows at 10° outside temperature (which is the height of foolishness if the goal is to minimize the heat load). With an exhaust-only ventilation system (the simplest and most reliable), most of the make-up air can be controlled by the placement of passive inlets, while the remainder of the air flow will be from the very small amount of leakage in the envelope and will disperse the fresh air throughout the house while not causing condensation (since only exfiltration can cause condensation as the moist air cools). Additionally, when the power is out or the timed fans are off, there will be some minimal flow of fresh air from the stack effect height difference of the passive inlets (which have internal flow restrictors).
While I can't control how a home occupant will alter the programming on the fan timers, I can be assured that there will always be some minimal fresh air exchange and not enough exfiltration to create a durability problem. Obviously, the key to limiting natural exfiltration is to make the upstairs ceiling as tight as possible, which is why I discourage the installation of any ceiling lights upstairs and use roof flashings on plumbing vents at the ceiling level. A drywall ceiling, taped to the drywall wall corners is a perfect air barrier, according to the Air Barrier Association of America. And it's always visible and easily repaired. Additionally, sealing at the foundation/wall interface is critical to limiting stack effect air movement. Then the remaining tiny leaks at doors and windows or under wall plates become non-problematic (though I seal those junctions as well as reasonably feasible, too).
The "green" building movement, which began with significant incremental improvements to the building envelope, has morphed into some sort of competition based on the unreasonable and illogical premise that, if a development is good, more of it is better and maximizing it is best. There is a point, however, in all things at which "the perfect becomes the enemy of the good".
The question, then, becomes: at what point are the diminishing returns not worth the additional investment – both in terms of financial cost to the home-owner and ecological cost to the world.
If getting to zero (or close to it) requires both making homes unnecessarily costly and using materials that have a significant (and often unknown) impact on the earth, then it does become a form of insanity.
I continue to stand by my thesis that a house fit for human habitation must be able to breathe (as all living membranes must do), must be composed mostly of natural materials (that are biologically compatible with our evolved physiology), and must function as passively as possible without reliance on external power sources or even site-generated power (which have off-site ecological impacts in their manufacture, maintenance and disposal).
There are natural laws which have governed the formation of the Universe and the evolution of life and that have maintained the fragile conditions for life in delicate balance for billions of years. Violating those natural laws used to be called hubris and, in our cultural mythologies, always resulted in human tragedy. Given the known state of human-induced ecological disequilibrium today, I think a more accurate name for a willful violation of Natural Law is insanity.
What is most needed in terms of a paradigm shift, and "green" building must be part of this, is a return to a millennial-old understanding of our place within a much more complex and intelligent Web-of-Life. Since, by that understanding, we cannot live without being intricately connected to all the other nodes of that Web, it should be obvious that we cannot survive if we isolate ourselves from Nature in hermetically-sealed boxes, connected by hermetically-sealed personal transport vehicles to hermetically-sealed work spaces. What is needed more than anything else today is greater connection, not further isolation. And let's not even get into the absurd belief that the internet connects us, when all psycho-social studies indicate that it isolates us inside our electronic worlds and reduces and diminishes real human interaction.
Interestingly, if you add the ASHRAE mechanical ventilation minimum requirement for a 2,000 SF 3 bedroom house to the ASHRAE assumed baseline leakage of 0.15 ACHnat, you get 0.375 ACHnat or 5.56 ACH50 as the minimum considered necessary for safe indoor air quality.
Prior to the new air-tightness standards, MN required a house to be no tighter than 4.5 ACH50 and WS no less than 5.63 ACH50 to avoid the need for mechanical ventilation. In other words, according to state standards and ASHRAE standards, a house must leak at a rate of at least 5 to 5½ ACH50 in order to provide enough air exchange for human habitation.
So it could be argued that any house tighter than about 5 ACH50 is too tight. But, because we have boxed ourselves into a corner with fuel depletion, cost inflation and global warming, and because we build with less durable materials that are vulnerable to mold and decay and are forced to limit both energy flux and mass flux (vapor diffusion) through our house envelopes to save energy, we must find a compromise between optimum human habitation and optimum energy conservation.
In the same way, human bodies prefer relative humidity between 30% and 70%, but our homes cannot tolerate anything outside a range of 20%-40%, so we are forced to compromise at the narrow range of 30% to 40%.
In terms of energy consumption, we are also forced to find an optimum compromise between air exchange for human health and air exchange for the health of a badly damaged planet. It seems clear to me that we can shift that 5 ACH50 limit down to perhaps 2-3 ACH50 without overly disturbing that balance and requiring ever more sophisticated technologies to redress the imbalance away from human habitability.
If anything, we should err toward habitability and, if necessary, find other ways to reduce energy consumption (such as a one-child policy, taxes on resource extraction, pollution and wealth instead of labor, a 90% reduction in military budget, and the stripping of civil rights from artificial legal entities called corporations).
How do rammed earth, adobe, earthship, cordwood, and strawbale homes stack up on the tightness/efficient front?
I was over in Russia shortly after communism died. I stayed in a tall apartment complex, one of many within a 1/2 mile or so of the subway station. Looking out the windows, there was a forest canopy, with these broad parks between each tall complex. In effect, folks would walk to the tram or bus or subway through gorgeous blocks of green. I heard later that with privatization the first thing everyone wanted to do was buy a car, and they wanted places to park them. Bzzzzzzzzzzz TIMBER. They didn't know what they had. IMO, there's nothing spiritually magical inherently universal about your walls breathing. It's just a whole myriad of science cause and effects. If your super tight walls can be eaten when your done using them (via composting for the garden) and if your super tight walls are in a sea of green, and your life interacts with that sea, then I think the angels or Tao or whatever will still find you inside your super tight walls. But those are some big ifs.
"Violating those natural laws" IMO, this concept is an oxymoron. Billions of years ago, stromatolites pumped a manufacturing byproduct into the atmosphere. It was a natural process and completely screwed everything up from their point of view. The product was oxygen. I think its hubris to think ANYTHING we do is not a natural process. Just because a species wreaks havoc on the recent ecological paradigm does NOT mean the process is unnatural.... that includes those pesky stromatolites and it includes us.
So what about those strawbale homes? Are they tight?
The Russians (and almost all Europeans), because they have a millennia-old connection to place, have shown far more respect for the land and for nature than us (literally) dis-placed Americans who came to conquer and exploit the land, its resources and its indigenous inhabitants.
What changed in Russia was not a political system but an economic one – from a socialist/sharing society to a capitalist/greed-based society. This blight, that we call the "free market" is infecting every corner of the world. It is a "me first" paradigm which puts individual freedom and wealth above all other values.
Violating natural law is no oxymoron, and it was the very definition of hubris: defying, through human haughtiness and arrogance, the gods and their rules.
Stromatolites, composed of cyanobacteria and later blue/green algae, have been central to the evolution of life on earth for 3.5 billion years. They were not willful creatures, with the hubris to step outside of Life's trajectory, but were the primary vehicle for Life's journey on the planet.
The Greeks knew all too well, as should we, that there is only one species on earth with the intellectual capacity and the spiritual vacuity to think itself superior to Nature (or the gods), to exhibit hubris and pride, and to create the conditions for tragedy (as we are now doing so well).
While there is nothing "spiritually magical inherently universal" about breathing walls, it is obvious even to a child that we cannot maintain the conditions of life inside a plastic bag (those warnings on the bags are for adults – the children understand). Few people with the financial resources would choose a plastic raincoat over Goretex, because common sense dictates that we are most comfortable and alive inside a breatheable shell.
There is not a single example of indigenous shelter, past or present, that is not composed of natural materials that provide – like our skins and cell membranes – a conditional and semi-permeable separation from our immediate environment. Life could not have evolved otherwise, since (as we now understand through epigenetics) DNA expression requires moment-by-moment signals from the environment. DNA is merely the blueprint, and nature is the architect.
Would I a house for happiness erect,
Nature alone should be my architect,
She'd build it more convenient than great,
And doubtless in the country choose her seat.
- Horace, 20 B.C. (famous for coining the terms "golden mean" and "carpe diem")
That's a good question. What about cob?
As for strawbale homes, tests performed by Jay Walsh of the Center for Ecological Technology on such buildings in NY, MA and VT in 2007 and 2008, resulted in blower door readings of 2.9, 6.9, 2.5, 3.1, 4.1 ACH50 (average 3.9, median 3.1, standard deviation 1.8). The 6.9 reading was for a small, circular, one-room building. The others were professionally-built homes of either 1 or 2 storeys.
A strawbale music studio that was built last year by a Natural Building class, using old recycled windows and with a stone chimney, tested at 17 ACH50.
It's challenging to get a strawbale infill or wrap-around building very airtight (because of the interface between straw/plaster and wood), but the range may suggest what is both feasible and appropriate for a natural shelter.
I suspect that most natural shelters would test no tighter and most often considerably looser.
I agree with most of what Robert said but exhaust only systems with air inlets for makeup air do not allow for a filtration system for those with allergies amd other breathing ailments..Exhaust only is a good and simple system but has limitations and I still believe cold, incoming air will pool on the floors.
This will sound horrible but, the human race needs to be allergy free. Cleaning air and surfaces, etc. to zero allergens is not a good thing to do for all of humanity, it actually could be fatal to our species imho. Those with allergies should do their best to get over their individual situations.
Mechanical systems need to be simple and all has to he fine with power off. RR is getting it right for me anyway.
Yet another nameless troll.
Off point warning...
:"What changed in Russia was not a political system but an economic one – from a socialist/sharing society..."
That's what I expected to hear from people over there, too. So I was troubled when the people I interviewed pretty much all said some "that's a load of crap.... to share you have to have a say in what is shared and under communism we had no say".
That's when I learned something that we are not carefully taught in this country.
Democracy and capitalism are NOT the same thing and do NOT require each other. One is about political power and the other is an economic model. Likewise, socialism and communism are NOT the same thing. Again, one is an economic system and the other is political.
The USSR was never a society of sharing because the people had no say. That's not my interpretation.... that's what they say themselves.
That concludes my off point alert.
Steve El
http://www.sciencedaily.com/releases/2009/04/090403104229.htm
I would love to visit the research lab in the above story. Basically they have these shakers, where they build full scale models of stuff and find out how big the earthquake has to be to shake it apart. Anyway, some folks are trying to perfect an earthquake-safe design for strawbale homes, that could be easily built with mostly indigenous materials and only a relatively small capital outlay. VERY cool. Add in energy efficiency and a lot of wood on a lot of fragile slopes might be spared the axe.
Clearly, Steve, you were talking only to wannabee capitalists and freedom idolaters.
Just as there is no necessary link between democracy and capitalism (in fact, capitalism flourishes best under fascism, which is why many American business leaders supported Hitler and attempted to stage a fascist coup against the FDR administration), there is no necessary connection between democracy and a sharing economy.
The quintessential American family was a tyranny that guaranteed and enforced equality of economic life (work and rewards). At best, it was a monarchy with a reigning king and queen. The most arguably successful sharing economy in the world was Cuba under Fidel, and it was for this reason that Fidel always had the overwhelming support of his people (regardless of US propaganda to the contrary).
Similarly, a recent poll of Russians by the Public Opinion Foundation indicated that 51% think that the Communist Party had played a beneficial role in society, Stalin is ranked the third greatest Russian in history, and life was considered best under Leonid Brezhnev. Iraqis today, particularly women, miss the security, prosperity and individual liberties they had under Saddam. A large part of the Afghan population supports the Taliban and miss the relative stability of their rule.
People desire security, predictability, and reliable human sustenance more than they do personal freedom and the inequality, insecurity and poverty that inevitably accompanies it.
As for the earthquake resistant straw bale house, there are Norte Americanos right now in Haiti teaching people to build with straw and other indigenous materials that will resist the next quake as well as the hurricane rains and winds.
Port-au-Prince is a classic example of what happens when a population ignores their indigenous architecture and resorts to cement block and tin roofs or large concrete buildings - collapse, death and devastation. There are many examples of indigenous earthquake-resistant architecture around the "undeveloped" world. It is only in the developed (and developing, meaning copy cat) world that we have forgotten the value of natural materials for shelter and clothing.
When I do the blow door test (I assume that's the right test to measure how tight/leaky a house is), what's the max air exchange I should be looking for without having to put in a mechanical ventilation system? I live in California with mild winter (winter low in 40s and very rarely go below freezing). I
f the building is too tight, how about if I just open a few windows in different part of the house slightly instead of using mechanical ventilation?
Mechanical ventilation requires additional energy consumption, so why is it better than opening windows slightly?
If I am wrong and I need a mechanical ventilation system, my biggest concern is how do you know when the ventilation system is broken/not working properly? I don't want the IAQ to suffer by using a mechanical ventilation system that I have no way of monitoring if it's working properly.
Amy,
I'm quite sure the CA building codes require mechanical ventilation to meet ASHRAE 62.2 standards (as do codes everywhere). Opening windows helps only if the wind is blowing and there are two or more open for cross-ventilation. But it's a poor way to guaranty that fresh air will be adequately exchanged or distributed throughout the house.
But a ventilation system can be as simple as using quality, efficient bathroom exhaust fans (which are required anyway) and operating them, in parallel with your wall switch or short-term timer, with a 24-hour programmable timer.
If the house is reasonably tight (as almost all newer houses are, ≤ 5 ACH50), then you should have make-up air inlets such as the American Aldes Airlet 100, combustion appliances should be sealed combustion, direct vent so they won't backdraft, and fireplaces and chimneys must be well sealed.
It's simple enough to determine whether the bath fan is coming on for the preset times. If the power is out, the backup is to open some windows.
Dougy my friend, my pal... Troll? hey... troll... their cool dudes man... you pickin on trolls?
and mice? all at once my firiend.... Where's your manners boy?
a non mouse... breathing unfiltered air and drinking from our lake unfilteres too... And it ain't killed many of us up my way yet Dougy... too bad for you pal. Enjoy your suburbia filtered life and hecklingg of mice and men
LOL... Dougy... yaa can now pick on mispellin and poor grammer.
I stand by my post... The world needs not to pollute air and live in the air that surrounds this fun planet we call Earth.
a non mouse (similar to a non-sequitur?)
(Doug... This mice loves all... I post in fun and with some actual belief at least for the fleeting moment in my posting. Keep the flame wars down by sticking to my content and debating it, ignoring it or have a laugh with me.)
To all non humans and anony mice:
Content means nothing without context. And the context of comments posted electronically is the identity of the commenter.
The medium IS the message. Anonymous posts contribute nothing to this site and should have been blocked from the beginning.
The moderators' refusal to do so is a measure of their misguided liberalism, just as the refusal of "progressive" organizations and groups to make their venues smoke-free in the name of "inclusiveness" is political correctness taken to an illogical extreme.
Anonymous posters are the ugliest of trolls, and there's no place for them in a sustainable world.
It is so wearying trying to argue against such confident falsehood.
http://www.sciencemag.org/cgi/content/short/329/5998/1478
Thank god for polls to tell us what people believe, else we might actually have to meet other people and ask them in person.
No wait, that's not what I meant. I meant, thank god for polls that confirm what we want to believe, but those other polls that disagree... they are all products of biased greedy bastards and cant' be trusted.
No wait, that's not what I meant either. I meant, thank god for polls that confirm what just one of us wants to believe.
Robert, I already have a pretty good idea what the former soviet citizens I have met would say if I showed them our conversation, and they'd say you don't know what you're talking about. But I'm not going to share their probable reasons for saying that because I'm certain you would only listen for purpose of arguing in disagreement, no matter what I might say. Instead, I'll refer you to.... well, to making a months long trip through Russia actually talking to people to see if you know what you're talking about regarding "sharing" under the communists. They'll have plenty of negative things to say about the present situation, but the ones who can think back to before the fall will tell you you're ignorant.
When you come back I will STILL not have oppositional defiance disorder and I will NOT listen to ANYONE who wants to not discuss nothing else.
.....I gotta back the time I waste on this.....
Bobby, that last post of yours is the most ridiculous one I have ever read of yours my friend and fellow God. I have a name as cool as you do dude and some others.... Tommy Jefferson... Some guy on a holiday... someone singing by river....Brooks'ie rambling water kinda fella...
Robert Riversong would ban my bad butt because of my name???;;;;;??????
No wonder you posted nice cap about Stalin and Saddam...
You know so much yet are so far out in you own little field. Love hearing reading your posts, don't stop for this mouse.
rammed earth and adobe (plastered) can be pretty air tight. your main leakage issues will be from windows improperly installed and poorly sealed envelope penetrations.
To those who would prefer to limit the "truth" of the world to the small bubble surrounding their own egos, anecdotal evidence is always to be preferred over large-sample scientific polling and surveys. Then you can be assured that the "truth" will always precisely match your limited personal experience and you will never have to suffer the indignity of having your prejudices challenged or undermined.
actually, I don't disagree with your report of the poll results. You've just put your own desired spin on those results. You have concluded that most ex soviets think they were "sharing" under to the old regime. Could it be at all possible that they would prefer the old regime over the present situation for some reason other than "sharing"?
I've been there. I've talked to many people. The answer is "yes". But that doesn't jive with your world view, so never mind. You don't need to talk to anyone, you already know the one and only true interpretation of everything.
I can see why you seem to view the soviet communist party as a desirable thing. You don't accept any views other than your own, and your an expert on everything.
(((( yawn ))))
I still don't have oppositional defiance disorder, and as long as every starry eyed neophyte progressive hangs on my every word I am not cultivating a cult mystique as a liberal thinker.
Steve El,
The Courteous thing
would be to start another thread.
I know it's off topic...
https://www.youtube.com/watch?v=k5JkHBC5lDs
If the mods wanna delete anything I write, I applaud the mods for their service and time.
If they do, hopefully they will also delete the original silly comment that the old soviet system was about "sharing" (#17).
Steve,
There are no mods
Martin is probably asleep right now ;--)
If Martin gets his kicks by listening to reasoned two-way discourse, where each side has an equal likelihood of learning from the other and changing its opinions as a result, then I'm surprised I can't hear the snoring from here.
I'm awake.
I tend to agree that off-topic posts are tiresome.
Here's the discipline I would prefer from regular GBA posters:
1. Try to stay on topic. If you want to discuss Soviet communism, start another thread.
2. Refrain from personal attacks on other posters.
For the record, I brought up Russia to illustrate an area of high density multi family housing in a sea of green, and that I'd be happy and connected to nature in such an environment even if my walls were super sealed. I did not take it off point, but when it went off point with such stubborn willful ignorance, my opinion is that other readers - especially newbie lurkers - should take stubborn and willful ignorance into consideration when deciding how much weight to give other comments from the same source.
I apologize if my efforts in that regard run afoul of what the owners of the site wish to achieve.
Steve,
There's nothing which inhibits and undermines "reasoned two-way discourse" more than the intellectually dishonest tactic of deliberately distorting another's statements in order to create the straw man that a dull blade can cut down.
You are clearly intelligent enough and have sufficient reading skills to know that I never imputed anything to current Russians other than a statistically validated longing for the old Soviet regime in which security trumped the false idol of personal freedom. The same has been documented in Iraq and Afghanistan (and likely every nation in which we try to foist free-market capitalism and the inevitable crime, corruption, wealth inequality and economic insecurity that accompanies it).
I am always prepared to engage in honest argument with a worthy adversary, but I have no tolerance for intellectual fraudulence, adolescent posturing or willful fabrication.
Appropriate that Steve's last post is in a font as diminutive as his reasoning. And my apologies for overestimating his intelligence and reading comprehension. I tend to give people the benefit of the doubt even when they don't deserve it.
For those who can't read the small print, Steve's retort was this:
"Silly me. Naturally you never described the soviet system as being about "sharing". I mean, that's plainly wrong so someone must have forged your name in post 17 and subsequent posts defending the false "sharing" statement. Thanks for your willingness to engage in honest argument."
Share is derived from the root "to cut" (as in plowshare). Its primary meaning as a verb is to divide and parcel out in shares or apportion. It is the foundation of ideological communism as well as indigenous communalism: "to each according to their needs; from each according to their ability".
It is only in a paradigm of idolatry to personal freedom that "to share" can possibly be understood as to freely give (or withhold) part of one's private property. Such Ayn Rand "ethical egoism" inevitably devolves into unethical egotism in which those who own far too much might deign to toss a few scraps to those who are bereft of the basic necessities of life, or into a modern "free-market" capitalism in which a large enough middle class is allowed to exist in order to insulate the filthy rich from the working poor and the dispossessed (at least until the banksters get so greedy as to destroy even that hedge against economic collapse and revolution, as we are witnessing today).
What the Russians (and many others in newly "democratized" nations) are quickly discovering is "The problem with capitalism is that it best rewards the worst part of us: ruthless, competitive, conniving, opportunistic, acquisitive drives, giving little reward and often much punishment -- or at least much handicap -- to honesty, compassion, fair play, many forms of hard work, love of justice, and a concern for those in need." - Michael Parenti.
Back at post #1 Martin offered a generic answer for the "how much Insulation is too much" question that could apply all climate zones.
Any more thoughts on the Insulation question?
I realize that PHPP and BEOPT offer specific answers to the Insulation question.
I am still waiting to here more about BEOPT.
Anything new with BEOPT?
Post 46.... worthy of deletion. Off point, dogmatic, and wrong.
Brooks and all... cellulose insulation. I would think after Riversong or some number cruncher greenie calculates cellulose's embodied energy verses the 50 year fuel consumption....
It would be nice for gba to do the math for the assortment of insulation systems recommended by gba.
So yes let's get back on topic.
A tough one.
I think that the point of diminishing returns on time and material should be respected.
At the same time I think it also depends on insulation type. Fill your boots with cellulose and avoid the more-unsustainable materials in all but the most neccessary places.
The foam beer-cooler is ultimately a dead end street. What's wrong with cellulose and strawbale beer coolers?
Lucas,
The "perfect wall" (outsulation) (beer-cooler)was seductive for me
probably could be done economically too
IF we did not desire windows and Architecture that makes us smile
I think that the Outsulation details become too complex/expensive to be used with Architecture in the "Real World"
"IF we did not desire windows and Architecture that makes us smile"
If that were true, you might consider buying a mothballed soviet submarine and turn it into a submersible house boat, thereby saving lots of real estate taxes. Never have to mow the lawn, either.
John,
Like it or not, northern builders will see more and more outsulation. The easiest way to meet the new energy code requirements for walls is to include foam sheathing.
Martin,
perhaps that is true if you are only striving for "code"
I think as the R-value/Foam thickness increases the challenge increases
The Building America Concord house is a high performance home...
but not affordable
unless you can afford to have Joe L. stand around and tell you where to put all the "gooey Stuff"
John,
I'm not arguing in favor of foam. I have long believed that the most affordable high-R wall is a 12-inch-thick wall framed with parallel 2x4 walls filled with cellulose. Robert Riversong's Larsen trusses work well too.
Martin,
Do you know of any outsulation projects that do not use Foam?
I think Lucas said it well
Foam is a dead end street
(at least that's what I think today)
John,
Maybe a new trend in building materials needs to happen. Maybe we should aspire to be more like the Europeans with their wooden insulated structural panels. There's a factory nearby that turns wood waste from forestry into fuel pellets for stoves. If a demand could be created that waste would serve us better as insulation than as fuel.
Here's a question: Why can't a balloon or truss framed stick structure be considered an outsulation approach?
A double wall that creates an exterior balloon frame or a Larsen/Riversong truss puts a lot of insulating value to the exterior of the rim joist and eliminates a heck of a lot of thermal bridging.
Architectural stuff like heavy outtie windows and pleasing shapes can be accomodated much more easily.
My goals for airtightness and thermal resistance are related to Eliminating the Ginourmous HVAC beast that is so typical/mandatory in my Hot/Mixed/Humid Climate.
I don't think we (my climate)can eliminate forced air cooling/heating but we could sure whack it down to a modest size if we had VERY good Enclosures.
Lucas,
right on
Lucas, what are the possible advantages in turning wood fiber into SIPs instead of double walls with a cellulose fill?
John,
Q. "Do you know of any outsulation projects that do not use Foam?"
A. Yes. There were many such retrofits during the 1980s. Most used Larsen trusses insulated with fiberglass batts.
Lucas,
I should say that I am more in tune with the last half of your post.
I think modified stick frame would suite more variety in architecture than a SIP approach
That was my thought too.
"Outsulation", which is also called the "warm sheathing approach" keeps the entire structural envelope (frame and sheathing) inside of the thermal envelope. The goal is to keep all water-vulnerable and structurally-significant materials (mainly wood-based) above the dew point to prevent condensation (at least most of the time). It's great in theory but can be weak in practice if, at any time in the life of the building, there is leakage (from outside or in) into the structural envelope which then stays both wet and warm enough for long periods of time for mold and decay organisms to flourish. It's a potentially fatal flaw, or what is known as an unintended consequence (which is an almost necessary concomitant of increased complexity compounded by the use of non-resilient assemblies that include plastics).
A double-wall or Riversong truss frame might keep the rim joists out of condensation danger and allow for a more continuous air barrier and thermal barrier, but there is still some framing and typically also sheathing out in the dew point zone. However, filled with a highly hygroscopic material like cellulose, these walls have a high capacity for moisture redistribution and release (depending, of course, on the permeance of the inside and outside skins).
The original Larsen truss system, designed for retrofitting existing houses, is a compromise between thick walls and outsulation, putting most or all the insulation outboard of the primary skeleton and skin, but requiring semi-structural framing and sheathing out in the dew point zone.
The only commonly-used non-plastic "outsulation" system I'm aware of is a straw-bale wrap around a timber frame (or could be a stick frame, as well). Straw-bale infill systems may place the framing in the danger zone and make air barrier continuity very challenging. But a continuous 18" thick "coat" of straw and clay is a wonderfully adaptive and resilient thermal envelope (though with some air barrier challenges at door and window interfaces). And there's few high-R building systems with less embodied energy than locally-harvested straw and locally-mined clay and sand (with some local horse or cow manure and a bit of hydrated lime).
While straw/clay may not be appropriate for all climates or agricultural regions or rainfall zones, it's a good model for what local, natural building might be for various geographic areas. Adobe in the southwest, cob in the northwest, cordwood-masonry in the woodlands.
What makes these shelters wonderful is that they are NOT beer coolers - but living, breathing membranes that support life in ways we don't yet fully appreciate (such as high negative ion count and ionic air purification).
Sorry for the confusion.
I don't mean SIPs as in foam sandwiched between OSB. I mean structural, insulating panels that are made from compressed wood fibre.
I'm not at my home computer at the moment or I could atach a .pdf catalogue with a wide variety of wooden insulators used in Passivhaus construction.
Personally, I am not a fan of SIP construction. Too much foam.
Lucas,
you may be talking about products like Pavatex?
Breathable structural "Racking Boards"
Exactly.
Ach so, thanks. Interesting stuff.
John, what happened to ductless mini-splits?
Lucas,
I think I could live with ductless mini-split myself
I think the general public will have an aversion to the "aethetics" of the Ductless
I consider it just another appliance
we got used to seeing TV's in our living rooms ..eh?
The LEED house that I designed uses ducted minisplits
but more as an afterthought
I have to admit the installation was poorly done..
I will post a link later and point to what I am talking about