Posted By toddm on 02 Mar 2012 04:53 PM
Nothing personal lbear. Just according the ICF industry all the respect and trust it has earned.

The ICF industry, the SIP industry, the wood frame industry, the SCIP industry, etc., they all have horror stories and they all broke peoples trust and respect in some shape or form.

There is no manufacturing technique that is infallible.

Just look at the tornado's that destroyed homes today, the wood frame industry reps will walk right in those communities and tell them to rebuild with wood again. Lives were lost and will be lost again in the future due to wood frame homes in tornado alley and the wood frame industry knows this but they don't care. It's all about money $$$, it always comes down to $$$.

I couldn't click on Brian's link but the ornl test he appears to be referencing is a system with 2 inch foam core, am I right?

I couldn't click on Brian's link but the ornl test he appears to be referencing is a system with 2 inch foam core, am I right?

Posted By cathsand on 04 Mar 2012 09:11 PM
I couldn't click on Brian's link but the ornl test he appears to be referencing is a system with 2 inch foam core, am I right?

Clicking on the link will not work since it was not entered as a link.  You will have to copy the link and then paste it into your browser.

Yes, the ORNL test was conducted on 2" of extruded polystyrene (XPS as opposed to EPS) with 3" of concrete on both sides.  The point was made that the reduction in R-value resulted from all of the steel connectors through the 2" of extruded polystyrene.  (Two inches of foam board is the thinnest that most installers would recommend for shotcreting.  Thinner foam could be destroyed by too much pressure during shotcreting.)  In other words, it does not matter how thick the foam is if the steel connectors that tie the two concrete wythes together conducts too much energy.  Think of this as aluminum fins on a copper heat exchanger like a car radiator.

If this is true for the shotcrete panels being used today, then it appears to me that it might be best to go with two inches of foam in the middle to stop the shotcrete from going through and then add 2" of foam board to the exterior after shotcreting and then stucco over the outer foam board.  That would insulate the steel connectors.  Another aproach would be to use connectors that do not conduct which some precast companies recently started doing. 

Posted By Alton on 04 Mar 2012 10:13 PM

Clicking on the link will not work since it was not entered as a link.  You will have to copy the link and then paste it into your browser.

Yes, the ORNL test was conducted on 2" of extruded polystyrene (XPS as opposed to EPS) with 3" of concrete on both sides.  The point was made that the reduction in R-value resulted from all of the steel connectors through the 2" of extruded polystyrene.  (Two inches of foam board is the thinnest that most installers would recommend for shotcreting.  Thinner foam could be destroyed by too much pressure during shotcreting.)  In other words, it does not matter how thick the foam is if the steel connectors that tie the two concrete wythes together conducts too much energy.  Think of this as aluminum fins on a copper heat exchanger like a car radiator.

If this is true for the shotcrete panels being used today, then it appears to me that it might be best to go with two inches of foam in the middle to stop the shotcrete from going through and then add 2" of foam board to the exterior after shotcreting and then stucco over the outer foam board.  That would insulate the steel connectors.  Another aproach would be to use connectors that do not conduct which some precast companies recently started doing. 

Alton, remember this thermal bridging issue was also a problem with some earlier ICFs. The forms had metal ties instead of the current plastic ties and there was a lot of thermal bridging going on with those forms. Now ICFs utilize plastic ties/connectors which eliminate the thermal bridging.

With the ORNL testing, as you mentioned, it was not the XPS that caused the drop in R-Value in SCIP, it was the thermal bridging of the metal trusses. I can see WHY manufacturers use the metal trusses, as this provides superior strength as it ties the 2 sides of the shotcrete and creates a monolithic unit. Unfortunately, this area of strength creates a thermal bridge issue. I don't think utilizing plastic truss connectors would provide enough strength in a SCIP, as there is no real strength in those connectors. Steel rebar is a necessary element in any concrete form to get proper strength, whether SCIP or ICF.

OK guys when did 2" EPS rate R20?  I want some of that foam.

Sounds like a study of a bogas panel made to test poorly.

My 9" foam walls would almost a true R90 at that rate.

Using metal for the trusses is probably the least costly material to use although metal will conduct readily.  

Either non-conductive fiber composites or epoxy-coated carbon fiber trusses would be strong enough to tie the wythes of concrete together but will cost more than wire trusses.  Some companies are already using this type of material to hold the components together.  See Thermomass and Altus Precast (Carboncast).

Most of the manufacturers make elevated R-value claims. Wood framed walls do not perform to the in cavity fill. The Foam in the panel is probably about R-10, The Manufacturer clamed R-20 equivalent to meet code. Equivalent means hype. 20 percent of the in cavity was lost to thermal bridging, this is not a surprise. It is not a high performance system as claimed and already cost too much. No system that costs more than $10 per foot of wall is a good deal. It is an expensive way to build a house. The economics of the system do not make financial sense. ICFs are cheaper, better and also already too expensive. The question is how to get the cost / performance equation cut in half. My new system delivers 7 to 10 times the R-Value for under $10 per foot of wall installed. I do not want to consider systems that deliver less than that cost/performance as an option. $10/R-80, or 12.5 cents per R-1. I do not see anything else close to that performance. This means a totally passive heated and cooled house can be built for no additional cost over standard construction. Passive annual thermal averaging that works in a building that looks reasonable. It is a matter of adoption of method and materials. It is not based on science that is not ready. Understanding how it works is all it takes.

I am not interested in building standard houses cheaper. They are energy hogs and do not lead to a brighter future for anyone. I build zero energy homes at a lower cost than a standard home. This is where we all need to and should want to go. Utility elimination enriches everyone. The owner spends $100,000s less over a life time on utilities. We do not have to build additional power plants and distribution systems which cost us trillions of dollars. You are no longer relying on the grid. You are comfortable no matter what happens to society, the grid, the oil supply, and world issues. Energy cost escalation no longer matters or affects the owner. What do all these benefits cost? Absolutely nothing. All that is required is doing things based on common sense and potential buyers expecting the benefits they should be receiving.


Brian

Brian,
What is your system?

What about using basalt trusses? Would that be feasible?

Brian, [zehboss]

I've gone through this thread and can't find a technical description of the system you are advocating.  It seems to good to be true, do you mind giving us some details particularly structural details.

Jim

The ornl study Zehboss is linking is almost surely the TMass wall system developed by Dow, The complete study is here: http://www.thermomass.com/files/thermomass_ornl_doe_thermal_performance_kosny.pdf

Two inches of XPS is a nominal R10 so the thermal bridging reported by Ornl isn't as dreadful as Zehboss makes it seem. The R20 is one of the DBMS adjusted Rvalues for the six climates Ornl models in DOE2. IIRC, TMass claims a mass-enhanced R35 in Phoenix. For Zehboss to embrace thermal mass and then dismiss efforts to quantify it as "hype" requires some pretty fancy intellectual gymnastics.

Diurnal averaging is not R-value because it only has value in specific climates, or for part of the season. On the other hand if you are averaging the energy balance over months, quarters or a year then you are accomplishing something very different, natural internal temperature at the deep earth temperature with no thermal input. Additional solar input or night time cooling can adjust the temperature as desired.

We use a hybrid of many techniques I have learned over the last 30 plus years. One method I favor is gabions, (a wire basket that is structural when filled of contained ballast), which is sided in and out with insulation and desired surfacing material you can obtain the mass and insulation values desired at a very low cost.

A gabion based wall normally does not require a separate foundation. It can be filled with pearlite, pumice, earth, sand, modified earth,(added cement), rammed earth, gravel, road base, concrete, etc. depending on what properties you want to achieve. You can put top soil in a separate 3 to 6 inch surface layer allowing a live wall. You can surface with a material that cost $1 per square foot that will last 100 years in that application with no maintenance.



Gabions are normally used in civil engineering applications. The established engineering of the structure is already complete and standardized. This is simply a repurposing of standard proven materials to a new application.

Filled with poured in foam and you get an onsite built SIP that is up to R-8 per inch of any dimension desired at much lower costs than purchased panels. The foam purchased in 55 gallon drums is 50 cents per board foot. This is about 16 cents per R-1 per square foot of wall.

You can use different densities of foam to have different structural properties. High insulating soils and pumice have R-values up to 2.5 per inch at a cost of 3 cents per board foot. This is about 1.2 cents per R-1 per square foot of wall.

Filled with a moderator a couple feet thick which for all intensive purposes thermally isolates the insulation layers in analysis making them act as separate independent insulation layers. R-10 outside, R-10 inside performs as R-100ish. This is because you establish two separate relatively stable smaller Delta Ts across the insulation layers.

You can use thermal solar to heat the center of the mass in the wall to further adjust the btus of thermal storage and to control the delta Ts in the system.

I use poly strapping for the center cross supports. This eliminates thermal bridging in the systems. Depending of the size, rating, quantity and placement you can achieve any desired shear ability and meet any earthquake zone desired.

So all this and some additional variables not mentioned gives me flexibility.

I can make a metal on metal SIP rated at R-100 that is 14 inches thick custom shaped to any house for $9 per spuare foot material cost and $11 per square foot installed cost. This method requires a post and beam structure and a foundation.

Or, I can make a 4 foot thick wall with natural material fill insulated in and out with thermal reservoir capable of heating and cooling in any environment for $10 per foot installed, no need for support structure and a separate foundation.

I can show you a specific example illustration of any one of these embodiments but it is not that simple. I can do so many things with the accumulation of the techniques. All deliver lower cost and higher performance over any available off the shelf system I know of. My designs and builds are not limited by standard products. The shape of the below house is done without excess costs. No other system I know of can do this easily.



The other big benefit is I can pull up to a site with 4-55 gallon drums, a coil of siding material, a trailer of tools and a truck, have a load delivered from Home Depot and can build a home short doors and windows.

My overhead is lower, my flexibility is higher, my build time is faster, my labor content is lower, my quality is better, the energy efficiency is higher and my cost are lower than any system available to my knowledge.

It is not simple to explain it all but, it works.

Brian

Um, Zehboss, unless you mean diurnal averaging we do not exist on the same plane, so to speak. And while mass effect is indeed seasonal and climate specific, the point of ORNL's testing and modeling is to provide a multiplier adjusting nominal R value to an annual-average mass-enhanced R value and allowing apples to apples comparison with conventional insulation. You'd know this if you had time to read studies on the Ornl site.

Thanks for pointing out the spell checker brain slip, I corrected it. It has little to do with the topic or the information. My point is that the adjustment is only valid in specific situations. It does not work in a continuously cold or hot time frame environment. Averaging temperatures over only a day often does not help much. It has almost no benefit in Alaska. It works great in the high desserts like Phoenix. As the time frame increases the power of the averaging applies to a much broader set of circumstances and provides larger benefits. Lots of manufactures claim an effective R-Value. This has very little value unless you have the just right environment. They seldom take the time to explain where it applies. They make it a buyer beware environment. I have found this particularly true about log home, adobe home and ICF manufacturers.

Brian

Gotta agree that sales people can say anything. But if mass effect claims can't be believed, even when they come with ORNL charts, why should we believe yours?

ORNL claims are correct. In order to understand and use them it requires additional understanding of where the numbers apply. Several examples of high mass houses exist that work but do not have mass appeal. Earthships, PAHS, AGS and others. It works. Secondly I am not selling a product. I am promoting a non product. Knowledge that will improve your bottom line and the bottom line of your clients. It will also reduce the amount of wasted energy and intern reduce the pollution in the world. I would hope all people believe in win win outcomes where everyone benefits.No one is hurt and everyone gains accept the standardized manufacturer and packager.

The other thing is it is all based on engineering and FEA modeling. Physics and thermodynamics do not change and simply express truths. You can choose to believe or not but it is not anecdotal. It is also easy to understand if you take a couple of hours studying how it works. Feel free to call me if you have additional questions. The principles are not new only the packaging. Do you believe in Passive House designs? It is also based on engineering calculations. Though they generally do not get into super high thermal mass. If you know how to make the calculations you can prove it to yourself.

The question has always been how can you get high mass inside the envelope at a low cost? I am just answering the question.

Brian
(360) 567-6681

Posted By zehboss on 06 Mar 2012 10:41 PM
ORNL claims are correct. In order to understand and use them it requires additional understanding of where the numbers apply. Several examples of high mass houses exist that work but do not have mass appeal. Earthships, PAHS, AGS and others. It works. Secondly I am not selling a product. I am promoting a non product. Knowledge that will improve your bottom line and the bottom line of your clients. It will also reduce the amount of wasted energy and intern reduce the pollution in the world. I would hope all people believe in win win outcomes where everyone benefits.No one is hurt and everyone gains accept the standardized manufacturer and packager.

The other thing is it is all based on engineering and FEA modeling. Physics and thermodynamics do not change and simply express truths. You can choose to believe or not but it is not anecdotal. It is also easy to understand if you take a couple of hours studying how it works. Feel free to call me if you have additional questions. The principles are not new only the packaging. Do you believe in Passive House designs? It is also based on engineering calculations. Though they generally do not get into super high thermal mass. If you know how to make the calculations you can prove it to yourself.

The question has always been how can you get high mass inside the envelope at a low cost? I am just answering the question.

Brian
(360) 567-6681

So what is your view/opinion on ICF homes (2x5" EPS x 6" concrete x 2.5" EPS)?

lbear,

ICFs are far superior to standard stick built homes. The ICF manufacturer’s products I have priced have always been relatively expensive. I have worked with several customers that decided on ICFs. They assembled easily and worked well. Finished walls were fairly expensive.

I built DIY ICFs that were a lot cheaper. Geo foam in 16 foot blocks bought in bulk were pretty cheap. They were easy to cut with a hot wire, hot knife and chain saw. We used 6 inches in and out 12 inch by 16 foot pieces. Groove one inch from surface fit metal flashing in slots for screwing to the surface. We punched holes in center of flashing. Wire aligned to the center of the hole. I strapped between the layers with poly strapping. This allowed adjustable cavity and wall insulation depths. This method was easy to build. It delivered double the insulation value wall for the same price. I did it in quantities for a single house. I assume the manufactures gets better pricing then little old me doing a house at a time. 100% markup over material costs seems high to me when I can make them on site for the material costs and a little labor.

Figuring out corner bracing took a little playing around. But the DIY system delivered twice the performance for the same price. I later built a DIY post and beam system with surface bond cement on the surfaces. It worked well but still too expensive. All that concrete in the wall was too expensive with the ICF.

I then went to a thicker internal wall and just ballast fill. That led me to Gabions filled with ballast and surfaced which is where I am now. The wall performance keeps increasing while the cost keeps reducing.

An 8 inch concrete wall requires rebar and 3000 psi concrete that is not cheap. A four foot ballast wall is cheaper and much higher in mass. The fill only needs to be 75 psi for structural and no internal rebar. This type of fill is 5 to 14 dollars a yard while concrete is 100ish a yard.

The concrete wall further requires a separate foundation poured on a separate day and cured. The ballast wall normally does not need separate footings. Ballast wall does not require curing time. Fill, vibrate, fill, and vibrate, until done with no down time. This is the highest performance/cost wall system I have developed. It beats all other systems with the same performance by a factor of 2 or more that I have found. It allows you to build a passive heated and cooled home at no additional cost.

Brian

Brian,

Are the Gabions filled, tamped and then set between metal skins that define the wall or are the empty Gabions set between the metal skins and then filled and tamped?  Which ever way the Gabions are used, do they keep the pressure off of the thin metal skins.  I guess I am somewhat concerned that the thick walls may push the metal skins out to create a bump unless a lot of bracing is installed on both sides of the wall.  Since I had not heard of Gabions before you mentioned it, I know nothing about the way they are used.