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What is Comfort?

As designers engage in an arms race to develop increasingly comfortable homes, green builders need to know when to say ‘enough is enough’

Posted on Jan 16 2015 by Martin Holladay

Buildings have had central heating for only about 140 years, and they have had air conditioning for only about 80 years. For most of human history, people took comfort in winter from a stone fireplace — somewhere to heat up a kettle or warm one’s hands.

Once heating and cooling systems were developed, almost everyone wanted them. Why? Because people want to be comfortable.

Comfort is hard to pin down

What is comfort? Definitions vary. If you are camping and get caught in a rainstorm, you’ll probably find that a dry sleeping bag in a dry tent is extremely comfortable. If you are spending the day ice fishing, you may find that a plywood shack equipped with a tiny propane heater is extremely comfortable — especially compared to the guy outside who is sitting on a Sheetrock bucket in the wind.

ASHRAEAmerican Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). International organization dedicated to the advancement of heating, ventilation, air conditioning, and refrigeration through research, standards writing, publishing, and continuing education. Membership is open to anyone in the HVAC&R field; the organization has about 50,000 members. has developed a standard (ASHRAE 55) that decrees that heating and cooling systems should maintain a building’s indoor temperature and relative humidity within a comfortable range: not too hot, not too cold, not too dry, and not too damp (see Image #2, below).

The PassivhausA residential building construction standard requiring very low levels of air leakage, very high levels of insulation, and windows with a very low U-factor. Developed in the early 1990s by Bo Adamson and Wolfgang Feist, the standard is now promoted by the Passivhaus Institut in Darmstadt, Germany. To meet the standard, a home must have an infiltration rate no greater than 0.60 AC/H @ 50 pascals, a maximum annual heating energy use of 15 kWh per square meter (4,755 Btu per square foot), a maximum annual cooling energy use of 15 kWh per square meter (1.39 kWh per square foot), and maximum source energy use for all purposes of 120 kWh per square meter (11.1 kWh per square foot). The standard recommends, but does not require, a maximum design heating load of 10 W per square meter and windows with a maximum U-factor of 0.14. The Passivhaus standard was developed for buildings in central and northern Europe; efforts are underway to clarify the best techniques to achieve the standard for buildings in hot climates. standard takes a similar approach, while noting additionally that the interior of a building shouldn’t be windy or drafty, and that the temperature of all of the surfaces in a room (especially window panes) shouldn’t be so cold in winter that radiational effects make people uncomfortable.

Standards that define a range of indoor conditions leading to human comfort are useful. All such standards note that not all people have the same ideas about comfort. Human comfort depends in part on whether the person is active or at rest; whether the person is fully clothed or naked; and whether the person is young or old.

Even if these factors are carefully controlled, however, humans differ. If two similarly clothed people of the same age are sitting in a room, one might say “I’m cold,” while the other might say, “I’m hot.”

Because of this human variability, standard writers have to specify ranges for conditions leading to comfort.

A family history of comfort

If I look back a couple of generations, I can easily document how comfort expectations have changed in my own family.

My grandmother was born in 1904, and grew up in rural South Dakota in a leaky frame house that was so cold every winter that the family banked the foundation with manure in the fall. I imagine that her bedroom was often below freezing during the winter.

As far as I know, my parents both grew up in homes with central heating (although my mother’s family had an icebox, not a refrigerator). If they wanted to experience air conditioning, they went to the movies.

My first memories date back to the late 1950s, when my family lived in a house with single-glazed windows in Boulder, Colorado. I remember waking up on winter mornings to admire the swirling, flower-like patterns of frost on the windows. Our eaves were often loaded with icicles — a sign that the attic didn’t have much insulation — and when I was having a bath, my parents used to make me laugh by breaking off an icicle and putting it in the bathtub for me to play with.

When I was growing up, cars didn’t have air conditioning. We would drive with the windows open, sticking our heads out like dogs.

No one wants to live the way we did in the 1930s

There is no turning back the comfort clock. It’s perfectly understandable that people prefer their homes to be air-conditioned during the summer. But advances in comfort raise the question: when does the arms race stop?

Would any of us recognize a motel room from 1960? These days, when you walk into a hotel or motel room — assuming you’re not staying in a hostel that caters to backpackers — you get more than a just a bed. You get a very wide bed — maybe two beds — with more pillows than a person could possibly use. In the bathroom you’ll find enough towels for a football team.

If the hotel offered you a bedroom like the one you have at home, you’d probably be insulted. That’s the arms race in action.

Passivhaus levels of comfort

I have written several articles noting that the Passivhaus standard often requires investments that aren’t cost-effective — for example, investments in thick insulation, triple-glazed windows, and Zehnder HRVs. When I suggest that it might be possible to specify less sub-slab insulation, double-glazed windows, or a simpler ventilation system, Passivhaus designers often respond: “You don’t understand! It’s not about cost-effectiveness! It’s about comfort!”

Sometimes they’re right: for example, when temperatures drop below 0°F, it’s usually more comfortable to sit next to a triple-glazed window than a double-glazed window.

Other times, they’re simply wrong. There is no way that a human can tell the difference between 6 inches of sub-slab foam and 12 inches of sub-slab foam.

But in all cases, these Passivhaus designers fail to ask an important question: how much money should we spend on comfort? If you get a chill when you sit next to a double-glazed window, maybe all you really need to do is put on a sweater.

If we establish a standard that insists that no surface in a house should ever be more than 7 F° cooler than the indoor air temperature, we are assuming that (a) humans should never have to suffer the indignity of sitting next to a window that has a surface temperature that is 9 F° cooler than the air, and that (b) spending lots of money on very expensive windows to meet our comfort needs is a good use of the world’s resources.

Two kinds of envelope and HVAC measures

I love envelope measures (for example, air sealing work and increased insulation levels) and HVAC solutions (for example, ductless minisplits) that are cost-effective. If investing in one of these measures saves enough energy over its lifetime to exceed the cost of the measure, it’s a great investment. Everybody wins.

What about envelope measures that aren’t cost-effective, but increase comfort? These measures make sense for homeowners who want high levels of comfort and can afford to spend more money on their house than the average family. But these measures shouldn’t be considered “green.” They are luxury features, not necessities.

Should occupants never notice anything?

Some Passivhaus designers and radiant-floor enthusiasts aim to create a house where we never notice the temperature. The temperature and relative humidity of the air should always be perfect. The goal appears to be for the occupants to think, “I notice nothing.”

In this vein, Mark Eatherton, the executive director of the Radiant Professionals Alliance, posted the following comment to a GBAGreenBuildingAdvisor.com article about radiant floors: “Being comfortable means that you are not aware of your surroundings. … You are not hot, nor are you cold. You are not over humidified nor are you under humidified. Ideally, you do not hear your comfort being delivered. Simply stated, you are not thinking about it, and if you are, then you are not comfortable.”

If this goal is achieved, it’s far from clear that our lives have been improved. It turns out that there is a paradox at the heart of this quest for perfect comfort: once it has been achieved, our lives feel somewhat empty. Most Buddhists have a fundamental understanding of this phenomenon.

If all human beings want is freedom from heat and cold, it would be hard to explain why kids remember camping trips with so much joy. Kids seem especially to remember the exhilaration of camping trips where everyone got wet and cold — and then got so hot and sweaty that they couldn’t wait to jump into a mountain lake.

There are two aspects to the phenomenon I'm describing. The first is that unchanging blandness seems to depress the human soul, in the same way that many nursing home residents are depressed by a diet without any hot peppers or garlic.

The second aspect to this phenomenon is more subtle; it was examined in depth by David Foster Wallace in his hilarious book, A Supposedly Fun Thing I’ll Never Do Again. When expectations are raised, as they are by Mark Eatherton's attempt to deliver a house where occupants are always perfectly comfortable, and as they are by the Passivhaus promise that indoor temperatures will be perfectly uniform, we are setting people up for dissatisfaction. Expecting perfection, homeowners notice the slightest draft, and the slightest draft becomes irritating.

We can be comfortable if we are willing to accept the world as it is

Designers and homeowners need to remember that it is sometimes OK to live in an imperfect house — one that feels a little hot in July and a little cold and drafty in January. In fact, this type of imperfect house might be more affordable (or even “greener”) than an expensive Passivhaus.

When you're hot, it might be time to drink a glass of lemonade. When you're cold, it might be time to put on a pair of fuzzy slippers and brew a pot of tea. After all, summer is supposed to be different from winter.

If you take this approach, you might discover that your imperfect house is fine just the way it is.

Martin Holladay’s previous blog: “Building a Foam-Free House.”

Click here to follow Martin Holladay on Twitter.


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Image Credits:

  1. Image #1: Pixar
  2. Image #2: Wikimedia Commons

1.
Jan 16, 2015 11:11 AM ET

Comfort is a moving target...
by Armando Cobo

Comfort is a moving target, even within ourselves. The older we get, the less acceptance we have for extreme temperatures. The funny thing is that it’s not any different than the other issues in our lives… Once we get comfortable with our new computer, we need to buy a new one. We really like our cars now, which are better and more comfortable than the one we had before, but less than the next one. Let’s not mention that I can break 80s like I used to, and it’s probably not getting better in the future, so my comfort level has been adjusted as well ;))
BTW, "We would drive with the windows open, sticking our heads out like dogs"... those were good memories!


2.
Jan 16, 2015 12:12 PM ET

Simple and sufficient
by ven sonata

In 2008 Catholic and Buddhist monastics got together in Gethsemeni Monastery in Kentucky for a 5 day conference called Green Monasticism, and we had to find a unifying theme or attitude. We ended up with two words "simple" and "sufficient". As a Buddhist monk I was very big on simplicity and the reduction of wants, however the Catholics rightly reminded me that sufficiency for some people means more, not less. Good catch! To find the golden mean we need to inquire into human nature.
Back to " simplicity". That is such a beautiful concept to apply to our homes and lifestyle. Complexity can make us feel like we are being harassed when we should feel at ease. In designing our homes if we look for "perfect comfort" we will introduce complexity and insufficiency, since, as Martin pointed out. perfect comfort cannot be maintained in a human body. Think about 'neutral feeling'. If it follows pain, it is experienced as pleasant. If it follows pleasure it is experienced as unpleasant.
So in the end wisdom is to know "what is good enough". That is something the fool can never know. That is why I like this idea of "the pretty good house" although maybe it should be "the good enough house".


3.
Jan 16, 2015 12:49 PM ET

Edited Jan 18, 2015 7:33 PM ET.

Nice idea if I wanted to be single
by Christopher Welles

For the purposes of marital harmony, I think the standards of "comfort" need to keep being driven as far forward as possible.

Given that each person's idea of comfort is different, trying to keep things in a zone where everyone feels comfortable can be quite challenging. Given the fact that everyone needs to compromise to live together, I don't think the outside weather should get a vote in the matter.

I would have thought my own situation was kind of extreme and unusual but from speaking with others, it turns out there are more couples in the same boat than you might expect. If I were single, I could buy into the whole idea of “we should just be more accepting of the weather”. Being married my stance is completely different.


4.
Jan 16, 2015 2:36 PM ET

Edited Jan 16, 2015 4:12 PM ET.

A+, Martin...
by John Semmelhack

....reminds me of a TED talk my wife and I watched together yesterday...for those who haven't watched it or won't watch it: the basic premise/spoiler - most humans need to feel some amount of vulnerability (but not too much!) and accept this vulnerability in order to be happy.

https://www.ted.com/talks/brene_brown_on_vulnerability


5.
Jan 16, 2015 3:55 PM ET

Edited Jan 16, 2015 5:08 PM ET.

Ahh Comfort....
by rjp :

Clearly comfort is a moving target but my trip down memory lane starts in South Texas in the fifties where "attic fans" meant whole house fans exhausting through the attic and central heat meant a natural gas wall heater in the living room. No insulation in the walls; almost none in the attic.

By the sixties, a new "custom" home of 2000 sqft had central air and heat, with the air handler in the attic feeding undersized ducts. Meanwhile the forced air gas heat was oversized but as effective as a roaring fire. Still no insulation in the walls, still single pane windows and maybe 3" of mineral wool in the attic. Public schools had no AC, poor insulation and single pane windows, so the quality of education suffered on hot and humid days.

Only in the eighties after the oil price shocks did we see wall insulation, double pane windows, house wraps and fiberglass in the attic (except under the air handler, around the recessed lights and sometimes around the attic water heater). Once oil prices impacted the economy a national energy policy was created. The eighties model is largely the same in the 21st century for "energy star" tract homes.

While trickle down economics did not seem to work, trickle down energy efficiency does work. Today tract homes in Texas can upgrade to spray foam, conditioned attics and two stage heat pumps. Comfort is what drives buyers to pay more for those features. So while the south did rise again economically (on cheap immigrant labor and oil), the benefits of trickle down education can't be dismissed and will likely have the most value.


6.
Jan 16, 2015 4:30 PM ET

Stasis and Movement
by Malcolm Taylor

One of the things that made early science fiction movies like 2001 so interesting when they came out was the fairly new idea of a completely enclosed and controlled environment, without any inputs to your senses from the environment beyond the walls. The whole idea of living in comfort and viewing the void beyond as an alien universe. I'm not so keen to aspire to that here on earth.


7.
Jan 16, 2015 7:05 PM ET

Edited Jan 16, 2015 7:17 PM ET.

Passive Haus requirement on annual energy use
by Jared Morgan

I built a house for $110/square foot. 3,450 total square feet, almost half of that is in a basement. I insulated with cellulose and sealed the house myself with foam spray and caulk before it was drywalled. I used the air barrier provided only by cellulose insulation and my air sealing.

I did all electric and ground source heat pumps. In an area that averages around $.10/kWh, I've averaged less than $200/month in utility bills. I also built with some other efficiency techniques that were reasonable on cost - framing interior walls so there is no gap, etc. I didn't do a lot of the expensive super insulation items - I didn't double frame, air seal the drywall, place insulation under my basement floor, etc.

I had a blower door test done to get an energy star rating. The HERs rating was 65 on the house and the blower door rated around 3. Come to find out the attic insulator didn't cover the insulation rated can lights (I know I know, I'm married) so we have a lot of leakage still in the attic.

I'm not in a super cold environment, in Kentucky about 2 hours northwest of Nashville.

After about a year and a half in the house, my annual use is 25,700 kWh. I have averaged 2,141 kWh/month. Am I wrong in thinking that the allowance for Passivhaus total energy use in a house is 11.1 kWh/square foot? I'm pretty sure that's the number I've seen.

That would mean to meet the annual usage requirement of Passivhaus I would need to keep my usage under 38,295 kWh in a year (11.1 kWh/square foot x 3450 square feet). It seems nuts that my house has met that threshold of annual use, and exceeded it, when we didn't do some of the crazy and expensive items that many do with Passivhaus.

I think this validates the point in the article - my house, unless i'm missing something, meets the Passivhaus annual requirement with pretty standard off the shelf and not that expensive materials. The exception would be the GSHP/geothermal, which has a payoff of 7 years. That part was expensive.

Did I miscalculate? Am I wrong on this? To the point of this article, we are very comfortable in the house and are very pleased with the electricity bills.

A couple other notes - I didn't do a ventilation system other than the bathrooms exhaust only. My HVAC system fan runs all the time - it has a variable compressor and variable fan unit, and I'm happy with it. The air sealing is not so tight that I need fresh air at this point. I'm also not convinced we need fresh air as much as we need humidity control, especially per research on the topic.

I'm not motivated by saving the planet - I respect nature, but my goal was saving money.

I'm curious to know if this is my miscalculation or if the annual use is that high.


8.
Jan 16, 2015 8:35 PM ET

Reply to Malcolm
by Lucas Durand - 7A

I agree.
The trend seems pretty clear though - ever increasing comfort is "progress", and "progress" is an imperative.
It's a pathology.


9.
Jan 16, 2015 10:26 PM ET

I long for the comfort of the grave
by Dan Kolbert

Like that?


10.
Jan 17, 2015 12:19 AM ET

Edited Jan 17, 2015 12:24 AM ET.

comfort and stress
by norm farwell

Ha, now the real goal of the passive house movement is clear: passification of the inhabitants.

If, as Mark Eatherton says, "Being comfortable means that you are not aware of your surroundings," then I think I'll pass on being that comfortable. And I don't think I want to live in a house that's designed to anesthetize people.

Living systems benefit from stress in many ways, as long as it's not repetitive or extreme. Girls who run and jump when they are young have stronger bones when they are old. I feel great when I am good and tired, and similarly there's nothing like an occasional fast to remind yourself that the wolf is still down there. This month's Atlantic Monthly has an article on the health benefits of being cold. Apparently central heating might have something to do with obesity.

http://www.theatlantic.com/magazine/archive/2015/01/does-global-warming-...

What did Churchill say?--"We build buildings, and then they shape us."


11.
Jan 17, 2015 10:39 AM ET

Edited Jan 17, 2015 10:41 AM ET.

Response to Jared Morgan
by John Semmelhack

The Passive House standard for whole-building energy use is based on primary/source energy use (not site energy), and is also based on a German definition of treated/usable floor area (not gross floor area). The nationwide U.S. average primary energy factor for electricity is roughly 3, so for your all electric house, multiply your site energy use by 3 = 77,100kWh/yr. Then, take about 75% of your gross floor area to get a rough idea of what your "German" floor area would be. 3,450 * 75% = 2,588. Now, calculate kWh/ft2....29.8kWh/ft2...about 2.7x over the standard.


12.
Jan 17, 2015 11:59 AM ET

In an odd coincidence...
by Curt Kinder

My fairly new home measures similarly to Jared Morgan's in size, cost and airtightness (if by a blower door "3" means 3 ACH 50).

It's US area is 3400; 75% is 2550; It used 7005 kWh last year. (3 x 7005) / 2550 = 8.24 kWh / ft2

My home is in North Florida, where we don't have winter worthy of the name, but it is nice to know a home can hit PH energy numbers w/o all the nonsense. It has geothermal HVAC, but I daresay it would stay below the PH standard with high end air source equipment as well. It's Man J comes in at around 30k Btuh summer and "winter"

I could zero it out with about a 5 kWh PV array were it not for shading.


13.
Jan 17, 2015 7:10 PM ET

A Builder's Idea of Comfort
by Kye Ford

I am a builder who works out in nature from the 95+ humid days to the -15F days here in Northern NY. My idea of comfort is that when I get home from a long day I don't want to feel like I'm still outside during the extremes. When I've been working outside all day in high heat and humidity I want to come home and be cool and comfortable. In the winter I want to come home and be warm and not have my feet be cold.
Martin as far as trying to connect some existential ideal to the pursuit of comfort. I think my internal debate went something llke this growing up, "wow its so cold I can't see out our windows because of the frost and wait let me go pick up my homework that just blew off my desk." Now in our new house its like this, "Hhhhmmm, wow it was cold outside today....Wait my feet aren't cold now...Let me go lie on the floor and play with my kids."
I think most people have many other things to fixate on and I don't agree with the idea that if they are comfortable they have somehow spoiled themselves and are missing out on one of life's great pursuits of being miserable.
I've lived on both ends of the comfort scale and I'm willing to risk spiritual and physical "blandness" for warm feet today. -13 below last night. Better put on two sweaters.


14.
Jan 17, 2015 9:08 PM ET

Beating a Dead Horse
by Peter L

It's pretty apparent that PassivHaus is not a realistic goal for homes here in the USA. It's a red herring because the US version "Passive House" is a realistic goal for homes in the USA. It's also apparent that Martin does not like PassivHaus and Passive House. One only needs to go back and read ALL the articles written and one can see a pretty clear picture; Martin doesn't like the Passive House model. His "pretty good house" is a jab at the movement. I am fine with that, everyone has his or her biases. Martin knows his building science but like myself and every other human being, we are not infallible and we have personal bias.

As far as interior "comfort" goes. I want an environment that is neutral. I don't want to experience cold drafts, sweating while sitting on my office chair or while sleeping, etc. If I want to experience the cold, I will go outside during winter. If I want to experience heat, I will hang outside during summer. If I want drafts and breezes, I will sit outside or leave my car window open while I am driving.

Like Kye Fords stated, "I don't agree with the idea that if they are comfortable they have somehow spoiled themselves and are missing out on one of life's great pursuits of being miserable."

Medical studies are clear that interior temps and comfort effect one's health. Even some sleep disorders can be traced to room temperatures of being too hot or too cold. Ideally a room temp of 68F-72F is better for sleep. Studies confirm this. Even if you pile on blankets and keep the room at 64F, it will hurt your proper sleep since you will begin to sweat and overheat under those blankets.

Bias aside, having a home that is a neutral and comfortable is better for the occupant and their health. Passive House is a good standard to try and attain.


15.
Jan 17, 2015 9:48 PM ET

Response to Kye Ford
by Nate G

But that's just it, Kye: when you are uncomfortable, comfort is a positive relief. But when you are comfortable all the time, that's when you start to have the itch to go camping and get cold and wet. It's all about the change in state. Whatever state we are in, we don't like to stay in it for too long. What silly creatures we are.


16.
Jan 17, 2015 10:13 PM ET

Pretty Comfortable House, Pretty Comfortable People
by Debra Coleman

As an architect of Pretty Good Houses, I can add that I enjoy working with people who want a Pretty Good House versus those that expect perfection in both drawings, the planning process and the finished home. The process is as much art as it is science. Most are happy in a Pretty Comfortable House. This article made me smile.


17.
Jan 17, 2015 10:40 PM ET

PeterL
by Malcolm Taylor

Isn't a car a climate controlled environment very similar to a house? I wonder why we don't get the rigid interdictions against opening car windows that we do when the topic is debated here about buildings?


18.
Jan 18, 2015 12:46 AM ET

Actually one of the few remaining pleasures...
by Curt Kinder

...of driving is the ability, in a modern car, of being able to nearly instantly change the interior temperature and humidity with the twist of a knob or push of a button without too much regard for the costs of doing so.


19.
Jan 18, 2015 5:27 AM ET

Edited Jan 18, 2015 5:29 AM ET.

Response to Kye Ford (Comment #13)
by Martin Holladay

Kye,
I hope that you don't think that my article is arguing in favor of uncomfortable houses.

Of course, when the temperature is below zero, almost all of us are grateful if we have a comfortable house to go to at the end of the day.

The point of my article is to get designers and builders to think about how much comfort we should aim for. Is the Passivhaus prohibition against windows with interior surface temperatures that are more than 7 F° cooler than the interior air temperature sensible? And if the prohibition is sensible, how much should we be willing to pay to achieve it? And why?


20.
Jan 18, 2015 5:33 AM ET

Response to Curt Kinder
by Martin Holladay

Curt,
Most Americans would agree with you about the pleasure of sitting in a modern car where you can push buttons to adjust the interior temperature to suit your every whim.

And yet there are still a few people out there who enjoy riding motorcycles. Or bicycling. Or walking.


21.
Jan 18, 2015 1:36 PM ET

response to Curt Kinder
by stephen sheehy

One of the few remaining pleasures of driving is putting the top down on my 2006 Miata, now sadly on hiatus in the garage until spring. I've been known to crank up the heat on a chilly October day, I must admit.


22.
Jan 19, 2015 4:56 PM ET

Environmentally responsible is not equivalent to economical
by Daniel Beideck

It is a far, far too common mistake to conclude that something is “green”, i.e. environmentally responsible, based on an economic analysis. This piece repeats that error when it says, “What about envelope measures that aren’t cost-effective, but increase comfort? … These measures shouldn’t be considered “green.”” Costs effective and environmentally responsible are not the same thing.

An example may help illustrate the difference. Consider a super duper window that has a very low U-value and is made very durable from earth friendly materials etc. The window is expensive and will take more years to save enough on energy costs to economically justify buying it instead of a typical vinyl window. Now consider that the window goes on sale at a deep discount and now costs the same as that typical vinyl window. What changed? The economics certainly improved. However, that window is no more or less environmentally responsible, i.e. “green”, than before it went on sale!

I’m not advocating that we must pursue everything that is greener regardless of the cost. It often makes sense to concentrate spending on those items with environmental benefits where the economics are also good. However, we need to be careful not to perpetuate the fallacy that something must be economically wise in order for it to be “green”.


23.
Jan 19, 2015 5:07 PM ET

Edited Jan 19, 2015 5:10 PM ET.

Response to Daniel Beideck
by Martin Holladay

Daniel,
I understand your point, but I don't think that it is very relevant to the topic of this article.

I agree with your statement that "we need to be careful not to perpetuate the fallacy that something must be economically wise in order for it to be green.” That's true. Cost-effectiveness is not the only lens by which we need to look as green investments, as you rightly point out; another useful tool is an embodied energy analysis.

When Passivhaus builders advocate 12 inches of sub-slab foam -- sometimes defending the action as "improving comfort" -- they are specifying more rigid foam than can be justified by an embodied energy analysis. In other words, the last 6 inches of rigid foam requires more energy to manufacture than the extra foam will ever save over the life of the building.

If a Passivhaus designer specifies $40,000 worth of European windows -- windows which may save only $50 per year compared to much cheaper double-glazed windows -- simply to save the poor homeowners the indignity of putting on a sweater for the three coldest nights of the year, the planet is not well served. The result is a wealthy North American sitting in comfort, but it's hard to justify the window specification as "green."


24.
Jan 19, 2015 10:58 PM ET

Edited Jan 19, 2015 11:05 PM ET.

Passive House NOT PassivHaus
by Peter L

Martin,

I think your point has been made numerous times over that PassivHaus requirements are not justifiable in the US market. So maybe instead of ragging on PassivHaus why not focus on the fact that PassiveHouse will not require the same off the wall requirements that PassivHaus has. So instead of throwing the baby out with the bathwater why not give PassiveHouse the credit it deserves.

As far as the $40,000 in triple pane window example you gave. The proper unbiased example would compare double pane window costs with triple pane window costs. It would then show that it is NOT a $40,000 difference but more of a $5k-$10k price difference between the two window types. In addition to that, people pay for comfort and luxury all the time. People spend tens of thousands of dollars on granite and other interior luxury and aesthetics that show a ZERO return on energy savings.

The example of the 12" of underslab foam on the PassivHaus project has been beaten to death. I think that dead horse needs to be buried.


25.
Jan 20, 2015 8:29 AM ET

Edited Jan 20, 2015 8:35 AM ET.

Response to Peter L
by Martin Holladay

Peter,
I agree with you that the proposed new passive standard under development by PHIUS will be an improvement over the German Passivhaus standard.

You wrote, "People pay for comfort and luxury all the time. " I agree. In fact, my article documents a continuous trend during the past 140 years, with designers, builders, and homeowners willing to invest an increasing amount for continuously increased levels of comfort. I'm not disputing that trend -- I'm challenging green builders to think about whether the trend should continue indefinitely, or whether there comes a point at which we say, "enough is enough."

While you are tired of hearing about 12-inch-thick subslab foam, Passivhaus designers aren't yet tired of specifying it. The new Friends School now under construction in Portland, Maine has 12 inches of sub-slab foam.


26.
Jan 20, 2015 11:46 AM ET

Diminishing returns - too much of a good thing
by Dan N

This all comes down to a word that goes against most American psyche: Moderation

And I think that's what Martin is getting at, or at least that was my take away, of which I completely agree.
We can't all live in a Passivhaus - it's an impossible achievement - nor do we need to.

Every house that exists today, can't possibly be made to fit those standards, and there would be little benefit gained by trying, because a house that's sealed up better with some extra insulation with double pane windows works just fine especially when you wear a sweatshirt around the house, and why not in January? It makes sense.

Make houses efficient but there is such a thing as going over board. Creating a gold standard doesn't mean everything should be gold.

Life is pretty much just the sum total of your experiences, and you won't want to experience hot chocolate if you're already hot.


27.
Jan 20, 2015 11:55 AM ET

Reply to Martin
by Daniel Beideck

You are correct that this was not the main focus of the article. However, it confuses people, consciously or not, into the false believe that doing a cost analysis is the same as determining the environmental benefit. Your example of the extra sub slab insulation is a good example of an analysis that looks at something beyond money to help determine if that next 6” is truly green. However, I disagree with your conclusion that the $40,000 windows in your next example are not green because they only save $50 a year. It’s probably not the best place to spend some extra money, but the cost has NOTHING to do with how green those windows are. In a few years fuel cost could soar and supply/demand could drastically reduce the price of the windows. That would dramatically change the cost analysis but do absolutely nothing to change the environmental impact of manufacturing and using those very same windows.

Saying this another way, choosing the green alternative is often a wise decision, but the wise decision is not always the green alternative. However, that doesn’t make the green alternative any less green.


28.
Jan 20, 2015 12:20 PM ET

Response to Daniel Beideck
by Martin Holladay

Daniel,
I agree with you that a builder interested in green construction has to consider many factors other than cost-effectiveness. I have written many articles that discuss these issues; here are links to two of them:

Calculating the Global Warming Impact of Insulation

All About Embodied Energy

In your opinion, the cost of windows has nothing to do with how green the windows are. I disagree. The cost of the windows is not the only factor to consider, but it is an important one. Our planet's resources are limited and poorly distributed. Homeowners in North America use a far higher share of our planet's resources than rural residents of Africa, and we need to consider whether our $40,000 window package is a good use of our planet's resources before we go ahead and place the order.

When an economic analysis shows that the energy savings attributable to a window upgrade are quite small compared to the cost of the upgrade, it is incumbent upon a green builder to consider whether the investment is wise -- or whether it simply reflects a North American homeowner's desire for greater comfort.

For more information on window upgrade payback, see Study Shows That Expensive Windows Yield Meager Energy Returns.


29.
Jan 20, 2015 2:22 PM ET

Edited Jan 20, 2015 2:37 PM ET.

reply to Martin
by Daniel Beideck

I’ve already agreed that cost is an important factor to consider when deciding between alternatives. However, cost is something quite different than environmental impact. Something MIGHT cost more because it is more resource intensive, has a greater carbon footprint etc. However, it could cost more for very different reasons, e.g. using alternative materials that aren’t as widely available or the like. An alternative, more costly material could very easily have LESS impact than the cheaper alternative. One example could be making the same window out of some material other than vinyl. A cost analysis might lead one to believe the vinyl window to be greener than the more costly alternative. Depending on what that alternative material is, that may or may not be the case, but cost is not what determines which is greener. Each situation must be determined on a case by case basis. It can get complicated. That’s unfortunate and a cost analysis can be tempting as a way to simplify things and make a quantitative comparison. The result is only as good as the underlying assumptions, however. An assumption that cost is a substitute for the amount of resources used is flawed and can lead to incorrect conclusions. In my opinion, we need to avoid this by being careful to not confuse the cost of something with its environmental impact.


30.
Jan 20, 2015 4:21 PM ET

Edited Jan 20, 2015 4:23 PM ET.

Well said, Daniel Beideck (post 29)
by Antonio Oliver

It's very often the case that cost increase is not proportional to resource use increase. I think windows are a pretty good example. Cheap double pane vinyl windows can be purchased for much, much less than PH triple pane vinyl windows. Yet the materials use difference between the two is not nearly as much. In fact some high performance window manufacturers will tell the consumer that the cost increase has much more to do with labor costs than materials costs.

Having said that, I generally agree with Martin (as I believe Daniel does) that cost effectiveness is not to be ignored. But as Dan B made clear in his post, "It's complicated."


31.
Jan 21, 2015 12:04 PM ET

Comfort or laziness? Comfort or passive survivability?
by Jodi Smits Anderson

I agree with this article in so very many ways. I also know, and it has been proven, that a variation in temperature keeps us healthy and our bodies functioning well. Sending kids outside to play is very important to their body systems effectiveness, and will decrease health issues as they age. Maintaining absolute 73 degree temps with humidity at 35-50% is not only unnecessary, but inappropriate.

However, the article goes astray in a few ways. First, confusing comfort with laziness does no one any favors. Comfort is not a luxury and should not be treated as such. Comfort must include, however, the societal broadening of our comfort ranges and understanding that we must work WITH our surroundings for our comfort. The time never was (though we convinced our selves it was fine) for us to expect our buildings to cater to our every whim without our thought or input or collaboration.

Secondly, comfort should not be confused with passive survivability. Passive house is not just about a comfortable home, but about making a home that does not need excessive foolish mechanical inputs when the envelop can be designed to maintain a healthy temperature range through thermal design. This is imperative in reducing energy use while maintaining comfort and supporting good health. It is not done to cater to a tight range of laziness in the building occupants - they will be very aware of their surroundings and of necessity will take part, collaboratively in maintaining their comfort.


32.
Jan 21, 2015 12:25 PM ET

Edited Jan 21, 2015 12:27 PM ET.

Response to Jodi Smits Anderson
by Martin Holladay

Jodi,
Thanks for your comments.

I agree with you, except for one point: my article doesn't (I think) "go astray" by "confusing comfort with laziness." I never referred to laziness.

Perhaps your reaction stems from the image from the movie Wall-E. The caption to the image accurately summarized one aspect of the movie's plot, I think.

We can debate whether or not the image was germane to the points I made in the article, perhaps. But I think you'll agree that my article makes no references to laziness.


33.
Jan 21, 2015 12:46 PM ET

Jodi
by Malcolm Taylor

I wonder if it would be more appropriate to substitute "passivity" for "laziness". There seems to be a trend, which is most noticeable in marketing, to ascribe virtue to things that will take care of themselves so we can get on with more important things (although what these things are is never specified). So Nest will monitor our refrigerators, make our shopping list for us and perhaps have food delivered without intruding on our precious time. Cars will drive themselves, houses will maintain stasis. Freed from the indignities that our physical existence has cruelly burdened us with through out history, we will finally be able transcend our bodies and live in our minds - maybe completely online!


34.
Jan 21, 2015 1:36 PM ET

Great Piece
by Daniel Cullen

Thanks MH for the observations and perspective of someone who is both a student of energy as well as humanity. Great read!


35.
Jan 21, 2015 1:39 PM ET

related rambling
by James Chambers

I appreciate this important conversation. I have read that human bodies are
40% more affected by surrounding surface temperatures than by air temperatures.
The book, "Thermal Delight in Architecture" by Lisa Heschong explores our natural
predisposition for a range of temperatures, rather than the constants of our built
environment. Heating and cooling remain the number one building related complaint
in office environments.

Mini- split product literature claims the inverter technology offers nearly precise
maintenance of the set temperature. This sounds very attractive to those of us who
are constantly aware of the 5 degree or more cycling of typical central systems and
the cold duct air at the start of every cycle. This technology also offers easier zoning,
so there can be a variety of indoor climates.


36.
Jan 21, 2015 1:47 PM ET

Comfort in contrast
by Jim Baerg

Comfort is not the same as physical pleasure. The highest pleasure that I can remember was taking saunas in my twenties. Outdoor wood fired sauna blistering hot til you just couldn't stand it. Then jump in the adjacent creek with the ice chopped open. For good measure, stand under the pine tree and shake the snow down. The next 5 minutes were pure physical bliss. Coming out of the cold to a wood stove or hot radiator is a similar, though milder effect.

Another recent example that has me wondering; I recently replace the furnace in our moderately insulated house. The big old furnace blew relatively cool air, so the cycling temps, and the mean radiant temps were within a small range. We were just used to uniform cool temps. The new furnace blows much warmer air that feels good when it comes on, given the cool radiant temps. When the furnace turns off, and the air temp slides down 2-3 degrees , I really notice the effects of cool walls and windows. Somehow though, I'm not liking the incessant cycling and I'm also finding the warmer conditions boring. I'm losing a connection to the outside temperatures.

I believe that humans need physical connection to the weather for psychic reasons. That includes changing light conditions during the day and some relationship between outside temps and indoor conditions. My optimal world would include a house that transformed through the seasons by opening and closing, and high utility prices. The house would need to be actively managed to control fuel use and also maximize physical pleasure.


37.
Jan 21, 2015 1:52 PM ET

Thanks, Martin. An excellent article!
by Ed Dunn

!


38.
Jan 23, 2015 12:46 AM ET

Great discussion, and many
by brian carter

Great discussion, and many good points.

I would like to look closer at the idea of comfort, and why it is a fools errand to try to make over the world in our biological image.

As organisms it is our fundamental task to find a balance with our environment. This begins before we are even born and we learn that gravity is a force we need to work with. Physically it goes on from there. I think of it as coping with resistance in all the dimensions we experience.

Depending on many things we individually decide what battles are most important in this process, and where our energies are most usefully spent. But one thing is certain. We need resistance or we are no longer alive. It is a physical and psychic necessity.

I have worked outdoors all my life, in all elements. Few people make that kind of choice. I enjoy comfort, or a cessation of resistance, when I need it, but I would feel sluggish and dispirited if I had to work in a cozy comfort-controlled environment for year after year.

I fully endorse the idea of making our homes as efficient, safe and comfortable as reason allows. I completely reject the ultimate notion that we need to plunder the world to do that, because we certainly can. That is also part of the balance we as organisms in an ecological system have to make. That part, I'm sorry to say, will never sink in, because it's not something we actually experience in the same direct way .

OK. It's Pink Floyd time. "When I come home cold and tired, It's good to warm my bones beside the fire."


39.
Jan 23, 2015 10:58 AM ET

Brian :
by Jin Kazama

I refrained myself from quoting this Time line a few days ago!!! ahah funny that you thought the same.

I've also worked outside a large part of my life, and i can't imagine living somewhere that would not let me experience the seasons, the wind, snow,automn leaves falling, the great february sun during a -20c sunny day!

Yesterday i got back home late, ~8pm, after a long work day and some additional road to go check up a cnc machine for sale. But i felt cold in the house, same temperature as been since begining of winter, nothing unusual, thermostats were reading ~22c all around; just felt cold with no reason.

I don't feel that way often, but for me, after reading this blog, it confirms that comfort is not a stable target for a human being.


40.
Feb 1, 2015 3:21 PM ET

Martin Holladay Article
by Dave Spencer

I have lived in my EchoHaven net zero home for over 3 years, and I think this article is confusing things. Martin has a passive solar house so he has an appreciation of what this type of home has to offer. I agree that "comfort" is difficult to define for everyone, but those of us in the business of promoting high performance homes use the word a lot and I find that I am always qualifying that term, since I had no idea what to expect of my home before living in it. After 3 years I have found that the house does not insulate us from outside changes, it CONNECTS me to the outside environment in a way I never expected. For example, after a few dull gray days, when the sun comes out the house is all of a sudden flooded with light and warmth. No drafts is a very good thing - we hardly ever get colds in the winter. Difficult concept to get across this idea of comfort but all I can say is that I have developed a huge emotional attachment to this home, which I have never had in any of my previous dozen or so homes


41.
Feb 1, 2015 3:55 PM ET

Response to Dave Spencer
by Martin Holladay

Dave,
Thanks for your comments. After reading your comments twice, however, I still don't know why you think that "this article is confusing things." You didn't cite anything I wrote that you disagree with -- nor did you cite any examples of confusion.


42.
Feb 13, 2015 10:16 PM ET

Love it!
by Ann Edminster

I'm late to the party, but have to say RIGHT ON, Martin! I'm actually a moderate PH enthusiast ... with the caveat that PH should be applied judiciously and with due consideration, not rigidly and uniformly. In other words, it should be seen as a useful tool, not adopted as a dogma. Equally good results can be obtained via the school of "Pretty Good Houses," provided the requisite knowledge and thoughtfulness are employed. In fact, PH and PGH spring from the same roots; neither should be condemned, neither elevated to the status of panacea. But of course we thrive on controversy, don't we?! Just as we thrive in a varied physical environment, so do we also in a varied philosophical environment. Carry on, all! It's a pleasure to partake in the dialogue.


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