" I know several people directly involved in the construction of these schools"

So in fact you WERE relying on facts not in evidence on the actual mass of the CMU walls in those buildings. That's fine, but don't leave us hanging/searching the document for it, eh?

And are the ORNL documents somehow WRONG about the benefits of keeping the mass on the interior? Do tell! (DOE2 modeling tells the same story, just in finer detail.)

It doesn't take a sophisticated modeler to find the knee points for wall R on commercial building using DOE2, but I'll try to dig up some web-examples for you.

But there are clear energy-use and comfort benefits to having the thermal mass fully inside the conditioned space

Not so clear, there are benefits and drawbacks - unless the thermostat isn't ever turned down/up. Which would be pretty wasteful in a school.

In a high mass building the advantages of setback strategies are very slim indeed, but the energy use advantages of the mass far outweigh the savings of using setback in a very low mass building.

Dana1,

You said:

"So in fact you WERE relying on facts not in evidence on the actual mass of the CMU walls in those buildings. That's fine, but don't leave us hanging/searching the document for it, eh? "

Yes and No.  Yes, I have a information about historical and future ICF construction including a some background for some of the schools.  However, regarding the "actual mass of the CMU walls" in those buildings -- it is only necessary to know that they were CMU to know that they typically exceed the heat capacity of 7 Btu/sqft F. 
 
The density of typical CMU material is 105 lb/ft³ for lightweight, 115 lb/ft³ for medium weight and 125 lb/ft³ for normal weight. The density of the clay unit material is 130 lb/ft³ and the density of the concrete is 144 lb/ft³.   Of course the actual Heat Capacity will vary with thickness but I know I don't need to provide you unit conversion examples:  You might see:  http://www.cmacn.org/energy/documents/cmu_const.pdf

Anyway, CMU is virtually always a mass system so it is only necessary to know that these schools were CMU. 

Incidentally,  Turkeyfoot was mentioned in the document as well (another ICF school) and one that I didn't include on the list. 


And are the ORNL documents somehow WRONG about the benefits of keeping the mass on the interior? Do tell! (DOE2 modeling tells the same story, just in finer detail.)

Perhaps extremely vague is more appropriate.  For example, they chart several ICFs (Insulation, Concrete, Insulation -- ICI) that don't exist (in the market) against several other mass systems (Concrete Insulation -- CI) and (Concrete, Insulation, Concrete -- CIC) that also don't exist (in the market).  Then the report extrapolates this information to multiple climate zones.  The report is also a mixture of various reports both theoretical and empirical and it reads that way.   ORNL is a fine organization but this is hardly one of their best efforts.   The report does clarify (in small print) that mass and R-value must be equivalent to isolate the effect of mass alone.   Most people wishing to quote the report miss that.   They might say that small mass to the inside beats a large insulated mass which might be true (but I doubt it) but this cannot be determined either way from the report as there is no varience in mass.   Also, according to the report, the difference is small enough (including both real and hypothetical wall systems) that I don't think much can be learned.   Please don't make me dust off and read this decade old report (again).

I'd rather pick your brain as to "WHY" ASHRAE and Department of Energy show a very clear uncoupling or disconnection between R-value with mass and R-value without mass.  E.g. in the report (subject of this thread) -- a mass wall with minimal R-value equals a low mass wall with significantly higher R-value in virtually all if not all climate zones reported (1-8).  

It doesn't take a sophisticated modeler to find the knee points for wall R on commercial building using DOE2, but I'll try to dig up some web-examples for you. 
 
I don't doubt that there's a point of diminishing return just as there is for foam thickness in the attic.  I am interested in when too much R-value hurts you and not in some generic sorta complicated academic way.  What I'm interested in is modeling what the mass is doing when it's insulated.  I know that it doesn't make a big difference but don't understand if the mass does basically the same thing (being insulated) and its just delayed via working through the insulation or what.    For example, I know from temperature probes that I've put in ICF buildings (under constrution) that an ICF wall will retain heat for days upon end and in fact even after 10 days in the 20's it will be a few degrees warmer inside the wall (heat coming up from ground?) than it is outside or inside the building.    ...and before you go there these are larger jobs where the heat of the chemical reaction is long gone.   The wall obviously tracks the ambient temperature it is just extremely extremely slow in doing so and really never does get there.   Regards.

In a high mass building the advantages of setback strategies are very slim indeed, but the energy use advantages of the mass far outweigh the savings of using setback in a very low mass building.

I disagree. Setback in low mass buildings is often a low double digit savings, more in something with limited hours like a school or office. The advantage of thermal mass depends on climate, but can be quite low - mid *single* digits.

Posted By jonr on 05 Jan 2012 11:24 AM

In a high mass building the advantages of setback strategies are very slim indeed, but the energy use advantages of the mass far outweigh the savings of using setback in a very low mass building.

I disagree. Setback in low mass buildings is often a low double digit savings, more in something with limited hours like a school or office. The advantage of thermal mass depends on climate, but can be quite low - mid *single* digits.

The area I am looking to build can see 30-40 degree temperature swings in less than 15 hours. It's not uncommon to be 70F at 3PM and then 30F at 6AM during winter. In the summer one can see 95F at 7PM and then 65F at 7AM.

This is where they should test ICF's thermal mass and how it relates to large temperature swings.

You can use my home build as the test and in return I would get a discount on my ICF construction costs...

Lbear: Another genius looking for something for nothing. Lots of them in this industry.

Posted By Ray Gladstone on 05 Jan 2012 07:31 PM
Lbear: Another genius looking for something for nothing. Lots of them in this industry.

What?

You have to be BY-FAR one of the most antagonistic people on this site. You constantly attack people. Why the moderators haven't removed you from this site is beyond me.

I am comic relief, a breath of fresh air, and the pin that deflates some of the astonishingly overblown egos hovering around here.

Lbear,

I enjoy your postings.  Please do not be distracted from your goal of learning and sharing.

Posted By Ray Gladstone on 06 Jan 2012 06:14 AM
I am comic relief, a breath of fresh air, and the pin that deflates some of the astonishingly overblown egos hovering around here.

In your own mind, apparently. Do not group people as egotistic when the intelligence levels of their discussions surpasses your own.

Izzie, I would suggest that there's a difference between knowledge level and intelligence level. For instance, I probably have a lot more knowledge than you do about some esoteric aspects of Victorian Literature. That doesn't imply that you're stupid, just un-educated on that topic.

I will concede to that, however the original point still stands. If you do not understand (or are knowledgeable) there is no reason to be condescending and provocative.

Posted By Alton on 06 Jan 2012 09:30 AM
Lbear,

I enjoy your postings.  Please do not be distracted from your goal of learning and sharing.

Alton -

THANKS!

 I will try and just ignore him.

A friend of mine who knows I'm enthusiastic about ICFs suggested I follow this discussion. If reading all the posts means I have followed, this I've done. Do I follow all of it, no. A lot is beyond my understanding.
It does seem to me though that there are several people who are so firmly convinced of the truth of their opinions that they should be writing memoirs and not engage in exchanges of ideas, where in fact they are not accepting anything from others.
Someone wrote something to the effect 'ICFs are not the answer to everything'. ABSOLUTELY! However, I believe there is strong evidence that ICFs are the easiest and most economical method available today to build strong, energy-efficient walls. I know from my own 20 years of working with ICFs that owners of these structures are delighted with what they have bought; strip malls, churches, residences, and schools. The Granby Middle school in Colorado (built of ARXX about 15 years ago) has certainly pleased its owners; I have a letter from them bragging on their building & its efficiency.
Maybe the Richardville school is merely the first net-zeroe school, but there is always a first of something. Maybe, hopefully, it will be the first of many such structures. Should we have stopped with the first public library in the USA (Boston Public Library, 1848), or should Andrew Carnegie have stopped with his first library?
I'm afraid my architect friends may get after me for writing the following, but I believe buildings should be designed first for their main purpose: shelter. Then designed for the occupant use. Aesthetics should come last. I have seen a lot of public money wasted on useless appendages to buildings just to give them some "zip" or "curb appeal", Okay, nail me up.
I believe this whole discussion began around an ASHRAE report which is much in favor of high MASS buildings, insulated, of course. This is what you get with an ICF structure.
Cheers.
FM

I surely enjoy this topic. It comes around regularly and I can count on it as being interesting and entertaining, and very educational. The physics stuff is beyond me. But for the record, there's very little about it that is absolute. R values are a good measuring stick. Not perfect, but it gives a decent datum for this topic.

Let's try to put it into perspective: Take all of those discussions above into account. Then, include that R value gives us a handle for discussing heat loss (conduction) through the medium. But heat transfer differs as you change from one medium to another, AND what the final coating is (flat black or gloss white?) (radiation).

Heat loss through the walls is an important consideration. But at times, it's penny wise and pound foolish. How much glass is in the walls? Single/ double/ triple paned? Do the window frames have a thermal break? How much air transfer is there? Who built it? Some construction methods can't keep air out, and many doors and operable windows don't. The final product is not PRECISELY predictable or calculable.

The green issue? The most “real” part about it is the part that has one jump through hoops to meet the esoteric energy targets. For reasons stated earlier, it doesn't (IMHO) make sense to hang that much on it when the real issues are ignored.

So it's got to be kept in perspective, as ColoICF pointed out. Frankly, given my choice, I'd take concrete any day. Why? Because I want it. I've been in a concrete home. It FEELS better. I got a bullet through the last house I lived in, and a tornado hit this one. I've felt air move through the house with 30 mph winds outside. I've felt how cold an outlet is in the winter. I'd like to be able to tune out the LOUD noise from someone's stereo (it takes mass to dampen low frequency sound). Should we mention fire? So, even if ICF walls didn't insulate better than stick frame (it does), I'd still build with it. It's just BETTER.

I kinda like hangin' out on this site, people telling each other the virtues of the product, how great it is, and the cool successes. Gives me fuel for when I go out to sell my product/ service. But if I ever get tired of hearing it and want to tout other methods, and stop hearing arguements about "overblown" merits herein, I'll go find another site touting stick frame, metal frame, adobe, hay bale, compacted earth, or whatever so I don't have to listen. But I'd miss y'all.