"Green" Construction

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I can't add counter-arguments because we are talking about completely different things. If you read their article, you will see that it says that most prefab *houses* are still using the same insulation system as stick-built. I said prefab *panels*, which are a different technology.

I thought I pretty clearly said that I am talking about relative energy efficiency *not* cost. If you are generating electricity by burning coal, then the state standards that you mention are just fine. If all you care about is cost; just turn the thermostat up and down as needed like Al Gore. Also, insulation 'experts' are usually interested in selling their particular technology, and there aren't any insulation experts that sell prefab panels and wall systems.

I hardly consider where I live Arctic---I've lived in the Lake Effect zone, and winter camped in the mountains for years never using a tent. This is my version of living in Florida.

Again, air leakage around openings is the result of shoddy construction, not design. See below.

But it is the opinion of physics. If you build two identical houses, and one has R19 effective walls and one has R30, you will lose and gain heat at different rates. I have the luxury (heuristic, if not economic) of moving between 3 space on a daily basis, one of which is poorly sealed R7, one at R19 well constructed, and one at R30 well constructed. Today, because of our conversation, I confirmed the test I've done in the past---placing the palm of my hand on the wall of the different spaces. In the first case, your palm starts and stays cold, in the R30 it is just neutral, and the R19 starts cold and ends up feeling slightly cool after about 15 seconds. What's interesting is that the R30 air temp is about 52 while the R7 and R19 are around 58. Outside temp is just under 40.
-tg

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Yeah, the terminology is a bit confusing. I've only heard them referred to as SIPs, so I didn't realize that's what you were referring to.

Right, but my reasoning was that if you weren't going to realize the cost savings in my lifetime (which is what one person said), then it would follow that they can't really be *that* much more efficient. Again, I'm talking about comparing apples to apples -- R19 insulation in stickbuilt homes with R38 insulation in stickbuilt homes. The SIPs are another issue altogether.
According to the stuff I've read on SIPs so far and the SIPs reps I've talked with, there seems to be little doubt about the superior technology and better efficiency. That's a non-issue. When it comes to SIPs, the *only* relevant issue is cost.
The builders in charge of these two projects reasoned that in order to keep their homes affordable for the average Joe, they aren't using SIPs.
The SIPs people of course claim that the reduced labor costs and lower utilities bills will mitigate the additional up-front costs, but again, they are trying to sell product as well. Being the reasonably intelligent person that I am, I'm fully aware that each party is probably going to present a slightly different "truth". ;-)
The totally neutral party I've been talking with -- an energy rater who is building his own home using SIPs, and who has no vested interested in either technology, had this to say:
"It is a cost issue. SIP's are great and significantly more efficient than stick-built framing (they use a lot less wood framing), but when we run the numbers in the energy model, it takes a while for the SIP's to pay back. For some people, it's worth the upfront cost. For builders who are watching the bottom line, especially on spec houses, they can't justify the increased cost. The house I designed for me and my wife is planning on using 4.5" SIP's (R26) because I understand the benefits, but I also know that it will take 7-10 years for the energy savings to pay me back for the increased cost of the panels. I was originally planning on 6.5" SIP's for the walls, but the payback jumped to 20 years."
So ultimately, as a matter of necessity, it has to be about cost. If I could find a way to afford the superior technology and not live in a 300 sq.ft. box, then obviously I would do so. ;-)

Hey, to each his own. I wish more people would plan those types of trips so fewer would haul their RVs and SUVs down the blue ridge parkway every summer. Eventually, we might be able to actually *see* the mountains through the smog . . . that is, the ones that the developers haven't yet shaved off to build McMansions for those rich yankee retirees who need their 2nd homes to escape the Florida heat in the summer.
Hey, if this global warming thing really takes off, they might soon be headed your way. ;-)

Of course -- but Energy Star certification is one way to ensure quality. The point is that if the house is sealed properly, which Energy Star certification helps to ensure, then pouring alot of money into thicker insulation is not necessarily a wise thing to do, according to these folks. If anything, I would think they'd be motivated to sell me thicker, more expensive insulation. Again, talking about stickbuilt here.

Are we talking apples and oranges here? In your experiment, are you comparing three SIPs walls or 3 stickbuilt walls?

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Why in the world would you think that? You can obviously buy one of those Tesla cars, and it is far more efficient than anything else, but with gas at 1.60 per gallon it is a lousy economic choice. Jeez ta, I guess should give up my quest to get people to think quantitatively and go back to knocking down windmills with my lance......

Again, that is not the right question for two reasons:
1) You are asking about 'what is really green', but you are deciding based on economics, not green-ness. 2) You can't figure out the payoff period with any certainty because you are making assumptions about the cost of energy in the future. By this reasoning, you should have bought a Prius two months ago, but now you should by a Hummer, since gas is 1.60. That way lies madness.

.......
Yes, ta, the guy who has been reminding people on this group for years about comparing apples to apples is comparing apples to apples. <grrrrr>
I know the 'data' is hard to believe---it is one of those neat things where the physics really comes home to you through a simple physical experience; these are all conventional walls of different thicknesses. The only difference is that 4 inch wall (R7 insulation) has different stud spacing 16" v 24", which brings us to a little discussion that may illustrate my basic point. This will require carefully reading and very simple math.
Consider a nominal 6" standard wall (5.5" actual) as described in your second house, which is claimed to be R19. Every 24", there is a stud, which is 1.5" wide. So for a 32 foot section of wall, assuming no doors or windows, there are 16 studs, yielding a total of 24" (2 feet) which is wood, and 30 feet which is insulation. Now the studs aren't quite 8 feet high, but let's round up, and multiply 2ft wide by 8ft high, which yields 16 square feet. This would be the same area as a 4ft by 4ft window!
If you add in the horizontal pieces of wood that tie the vertical studs together, and the extra pieces that go around doors and (actual) windows, the usual estimates are that 19-24% of a wall is wood, not insulation. Now, the R-value for that thickness of wood is in the R7-8 range, which is only slightly better than an actual window, So, conservatively, about 80% of our wall is the R19 insulation, *but* 20% is the R8 wood.
So how do we tell if the builder is serious about green-ness, and what are the economics? You can nail some siding on and *claim* that you have an R19 wall, which is what your second house seems to be. Or you can first apply a 1" layer of isocyanurate rigid foam, which has an R- value of about 6.5-7.5. What that does is raise the value for the 80% that is fiberglas insulation to say 26, but also bridges over the 20% that is just wood, raising that to 14---which is above your state mandatory minimum. Going by *retail* prices, the cost of doing that for a 32ft section of wall is 8 pieces times $18 or $144 (in reality less because of windows and doors). I think you can do the math to extrapolate to whatever size house you are looking at, and see that compared to the total price, the difference is trivial.
Now we can look at some of the other features I've mentioned, and there will be similar (relative) numbers. But those small numbers add up to profit margin for the builder; even on 12 homes, a few K per house is a big deal, and they have little motivation to give that up. FWIW, I'm just trying to make you aware that if you wish to be greener, and/or don't believe that there will be a magic cheap energy source discovered in the next few years, it might be worthwhile to study up on the details *and the actual numbers*.
-tg

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No, I obviously can't, since I can't afford them.

It wouldn't be a lousy economic choice for someone who could afford it, but it certainly would be a lousy economic choice for me. Actually, there's no choice involved at all, because they are obscenely expensive, by my standards (which are the only standards that are relevant, since this is my house we're talking about). You cannot determine what are good and bad economic choices unless you consider the financial state of the buyer.
Obviously Larry Hagman can afford to be a lot more "green" than I can.
You seem to think that efficiency is the only relevant factor and that economics are irrelevant (in my original post, I said "bang for your **buck**). That's fine if you're an academician writing a paper or preparing a lecture about some theory or ideal. However, for those of us actually dealing in reality, we have real housing needs with real budgetary constraints that must be considered.

The right question is: how efficient can I get within my financial and other constraints. All other questions are strictly academic and of absolutely no interest to me.
The guy who wrote the paragraph above has his own criteria, which may or may not be different from mine (I really don't know his financial condition, so it's not for me to judge). If I were in his place, I may or may not choose to install the 6.5" SIPs, depending on how much more they cost (i.e., if I could afford to take the hit, the extra green- ness might be worth it . . . just as if I could afford to buy the Tesla, then the added efficiency/green-ness might be worth it -- "worth" being used generically, not strictly financially).

No. I am deciding on *both* economics and green-ness. I don't think it's that complicated a question really. I have X amount of money and I want to achieve maximum efficiency within that real-world constraint. Other real-world constraints/factors include geography and size.

That's true. I have no idea what kind of model he used, tbh.

Nonsense. I wouldn't buy a hummer if gas was .60/gallon.

You misunderstood. I said are **we** talking apples and oranges. That is, are you talking about one thing (SIPs) and I'm talking about another (stickbuilt).

Right, so all this an argument for SIPs, which I am already familiar with. No studs = more efficient.

Ok, that's good to know. These are things I can investigate.

Yes, I agree -- that's why I'm asking these questions. ;-) And again, I do appreciate the information. I'm simply trying to discover optimal efficiency at a price I can afford and in a location and size that is suitable to me.
I have no allegiance to these two examples that I've given -- they're just the first two that I have come across. I was talking with another builder this weekend who may be able to sell me a house using SIPs that I can actually afford (the two that I had investigated prior were way out of my price range).

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<snip>
Ok, I've finally figured out what I've been trying to say and perhaps can now do it in (somewhat) fewer words.
One is obviously constrained by one's budget, location, and size requirements, and you are obviously more conscientious than most because you are doing the research. But I am concerned that everyone treats efficiency by a different standard than they do all the other factors *other than* budget, location, and size.
The problem is that there is no other feature of the house which is required to 'pay for itself' in some number of years in order to be a desirable choice.
Let's say you are buying/building a 64x32 house (I don't think you are going to buy a McMansion any more than I think you are going to buy a Hummer.) That would be 6 of the above wall sections, and let's say the cost to add those rigid foam sheets comes out to $1000. Not SIP, but a similar effect by bridging over the framing members.
Well, lots of people would gladly spend $1000 to get, say, a nice front door---maybe with one of those little semicircular windows over the top. But they would never even think to ask whether that was going to 'pay for itself' in 6 years or 12 years. They simply accept some risk v benefit, since when they sell the house such doors may be out of fashion, or maybe there's a revival, so they could lose or win, but probably they just like knowing that they have a nice door and are happy to spend the 1K.
But then, why don't we apply the same approach to energy efficiency? Why do people have to see some calculation that the choice of extra insulation is going to be economically neutral, and in a specific time frame? Why not apply similar reasoning: It could be that energy will become cheaper, or more expensive, and you could lose or win, but by making that choice you will at least be a bit more physically comfortable and have contributed something to the future.
So my question is, why is spending that $1000 such a big deal in one case, but not in the other? I'm not saying someone should choose (if the choice were available) the insulation over the door, or vice versa. But it should be a matter of preference, without the double standard that seems to have been created involving 'pay-back periods'.
Does this make sense yet?
-tg
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tg, I think you are trying to convince me of something that I don't need to be convinced of. :-)
I don't believe I stated anywhere that any choice I make about efficiency has to pay for itself over x amount of time (I cited the Rater's example to illustrate the cost differential, which is a relevant factor, and noted that his decision is not necessarily mine. And I cited the insulation guy's comment that you would not see the cost savings in your lifetime to illustrate that the two choices are not *that* different in terms of efficiency, according to him); I just said the choice has to be affordable. These are two different things.
I most certainly would pay an extra thousand dollars to get the extra efficiency in your example above, regardless of whether I could gain that money back in utility savings (although it would be foolish to not want that as well), as long there was some tangible benefit in terms of efficiency (and I believe you that there would be).
That's precisely what I was getting at when I wrote:
"The guy who wrote the paragraph above has his own criteria, which may or may not be different from mine (I really don't know his financial condition, so it's not for me to judge). If I were in his place, I may or may not choose to install the 6.5" SIPs, depending on how much more they cost (i.e., if I could afford to take the hit, the extra green- ness might be worth it . . . just as if I could afford to buy the Tesla, then the added efficiency/green-ness might be worth it -- "worth" being used generically, not strictly financially)."
in my previous response.
So the bottom line is that the decision doesn't have to result in a break-even or better financial scenario, but it does have to be affordable. If I had $1000 (or $5000 for that matter) of financial wiggle room, then I would choose the "greener" solution, assuming there was a reasonable, tangible (environmental) benefit of doing so. On the other hand, I would not spend another $1000 (or $5000) on something if the benefit was going to be negligible. So I would just need to be confident that the investment was going to be worthwhile (again, using "investment" in the larger, global sense).
I've made the same argument countless times in discussing factory farming with people . . . that the true "cost" of a factory farmed pork chop is not built into the price tag, when you consider other environmental, health, and ethical side effects. As a matter of practice, I've always been willing to pay the premium food costs up front to prevent larger, more pervasive costs down the road. I do this despite the fact that the locally raised, organic chicken that I (usually) buy is not going to provide me with a financial return on my investment. The other benefits (health, environmental, ethical) are "worth it" to me.
I short, I'm willing to eat the costs of a greener implementation, as long as I can afford the upfront premium costs, as in my food shopping example. That's a non-issue.
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Ok, ta---you buy that organic chicken, and I'll work in my R-30 building, and between us we'll save the world. :-)
Anyway, I'm glad that the attitude I described doesn't apply to you, although from what I can see, it is actually the norm.
But I would still question your use of the payback period as an indicator of relative merit, because of the price factor. IOW, doubling the efficiency is always twice as 'good', whether I am paying $2 for heating oil or $4---but of course that price greatly affects the payback period.
Say, it just struck me that this is some kind of prisoner's dilemma deal, actually---if everyone buys efficient houses and cars, the price of energy will drop, and then they will all complain that the investment wasn't worth it.
Shhhhhh..........
-tg
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Ok, I see your point -- I was using the utility bill as a gauge of efficiency because it is a tangible measurement and it is one I can readily understand. I don't understand all of the technical details behind the various insulation options (or even what all of the options are), so financial savings made "common sense" to me.
So how would I measure the efficiency gain with the added layer of foam? It makes sense to me that it would be more efficient, how can it be quantified?
(your physical experiment with the hands on the walls makes sense as well, but how can that be quantified?)

(laugh)
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Be careful what you ask for ta:
http://dt.fme.vutbr.cz/enviro/Pohoda/thermal.htm
Now that you've read and absorbed that, perhaps we can refine your questions as I suggested earlier :-)
I think when you say 'how do you quantify increasing R value?', what you really mean (since R is already a quantity) is: "what is the relationship between increasing R value and my need to turn the thermostat up or down?". Your sources are correct that the relationship is not linear---there is some degree of 'diminishing returns' from simply increasing R. But it is difficult to tell how this affects your particular case without more info on your preferences and options.
For example, as I said, I am more concerned with staying cool when it gets hot, so my 'bang for the buck' involves an R50 roof and good thermal mass as top priorities. But knowing that, we have to ask: Does a particular roof design work with the style of house that you want to get? Will the builder be willing/able to modify his standard design at a fair price? Do you prefer carpeting to tile?
So the 'quantification' requires that we begin at least with some parameters or ranges.
-tg
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Oy.
I'm planning something like this:

http://www.youtube.com/watch?v=vcd8BiIU13U

;-)

I would think you'd be more concerned with staying warm up there in the north pole. Where I'm going, the summers are cooler and the winters are mild. And although the climate projections are hardly what I would call a sure thing, warmer is probably the safe bet. But honestly, planning for any more than a few years in advance is a crap shoot.

I don't know.

No, I'd like to do concrete floors downstairs+hardwoods upstairs if possible. Otherwise, hardwoods throughout, but ceramic tile in the kitchen.

I'm really talking about a pretty simple, 1300-1500 sq. ft. house here, so design is less important than function to me.
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At least with the 44 acres you can gain some distance from the pig farms---although I suspect even that isn't really enough :-(

Sure, that's what they all say;-). If you are really going to end up that small, with 2 stories, and no frills, what I've suggested so far would probably allow you to live in that climate and never use a drop of energy specifically for heating or cooling. And just in case this is the one time I've ever been wrong about anything, the most sensible thing to do is put in electric baseboard heat, which will save a whole lot up front. A couple of window-sized AC units upstairs will turn the place into a refrigerator should you so desire.
I'm not really exaggerating here, ta. The insulation plus thermal mass will keep you very comfortable. I would see about conventional walls as I described earlier to get about R24, and maybe the roof could be the R50 SIP given your small span and low snow load. Definitely get 5/8 sheetrock on the inside; again this adds just a little to the price. I don't know anything about concrete as a residential floor but I assume with some kind of epoxy paint it should work fine.
There are designs for that configuration (small 2-story) out there but you will have to do your own research on it.
-tg
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The hog farms are all on the other side of the state. That way when the hurricanes come, the hogs can go for a spontaneous swim:
http://byrddroppings.typepad.com/byrd_droppings/2005/08/flashback_hurri.html

That's seriously what I'm looking at; that is the size of my current abode. Ok, I don't want to live in a box, and a window or two *would* be nice, but I'm not too hung up design features. (btw, western NC has some of the most expensive housing markets in the state and entire region -- did I mention those rich yankee floridian retirees and their 2nd McMansions?).
What about straw bale homes?

Really? I mean, average lows in the winter are around 30, but that's still pretty damn cold. I spent a couple weeks in December in western NC once that only had a single wood stove as the sole heating source (but it had these huge picture windows). It was c-c-c-c-old.
Many of the older homes in Western NC don't have A/C at all, other than a window unit or two, but all of them have heat.

I know zero about thermal mass; I'll have to do some reading.

Cool, thanks for the information.

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Ok, I didn't realize you were talking about higher elevations. But you will still use very little energy over the course of the year--- even in the mountains, your winter is relatively short.
Sure, you don't care about design features but now you want a picture window. ;-)
One of the tricks I've seen, depending on the layout of the house, is the use of clerestory windows to give a lot of light. This allows you to have smaller windows at 'ground level', so you don't affect the radiant temperature as much (see that reference I gave you).
Also, if you just want the coziness effect, throw in a wood or pellet stove for the living room. Both use local renewable energy sources.
-tg

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No. I mentioned the windows because that home lost tons of heat through that window, so that contributed to the c-c-c-c-old.

Yeah, I like the idea of a wood stove.

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In article <8b939634-ea9b-44bb-93d7-230c577a01cc@

There is no such thing as "green" construction. If you want to save the environment, quit having children. Every child that is not born cuts your ecological footprint by 50%.
--
For email, replace firstnamelastinitial
with my first name and last initial.
  Click to see the full signature.
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Larry Caldwell wrote:

No it doesn't.
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wrote:

It is obvious that human freedom and prosperity can be optimized by reducing the population, and I have been advocating that for decades. However, you need to learn a little math before you jump into the fray---your statement makes no sense.
-tg

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wrote:

Agreed, the poster's math is meaningless, but the concept is the main and most important issue. Overpopulation is the issue, more than anything else. The earth currently supports many times the number of people that it should, and as a result as population grows unchecked, the quality of life declines for *all* people.
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PeterD wrote:

By what standard? What is the population that the earth "should" support?
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re: population limits
Apparently Malthus ultimately prevails
The situation will probably not change, although credit China for its efforts, because it's disliked for it's restriction to one child, and allegedly women are in shortage because of it, so it hasn't worked well
The RCC will change--it eventually does but usually post facto after the damages are done
So, the Bush II regressive politiks does what it does, and i presume whatever progress that Clintonism brought about has been gutted by prevailing reactionary GOP politiks
The irony is his kin/grandmother was allegedly an ardent Planned Parenthood official type
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