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Henry Tiver
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What type of natural building method will produce the highest R-value? I was looking into log or cob, but I'm open for suggestion.
 
Bill Bradbury
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Hi Henry,

The highest R-value per inch for a solid mass wall is achieved with clay/straw. A 12" thick wall can achieve R-19 without mass wall effect being considered. The actual performance of the wall can be much higher than a code minimum stick framed R-19 wall with 5 1/2" of fiberglass insulation.

Natural building design has many factors that effect the thermal performance of a building, but R-value is a start.
 
Troy Rhodes
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I like a double wall frame, filled with blown in cellulose. I'm working on building #3. First two turned out great. 12" thick walls gives you pretty close to r-50.

The lowly 2x4 is sustainable/renewable, and the cellulose is re-used newspaper with a little borate for a fire retardant.

Inexpensive, fast to put up, widely available. Gives those beautiful wide window wells.





troy
 
Jay C. White Cloud
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Hi Henry...

What type of natural building method will produce the highest R-value? I was looking into log or cob, but I'm open for suggestion.


First let me second all of what Bill B. shared. Of all the traditional, and common "natural" materials "straw clay" (clay slip straw...as it goes by several names) is perhaps the one to facilitate the highest "r values-u-value relationship." There are esoteric means, methods and materials from wool, to cattail down, yet these are neither easily facilitated nor always the most enduring.

I for one even question the long term durability of "cellulose" (a.k.a. recycled newspaper) in most "modern builds." In some methods, like where I would employ saw dust, I think cellulose has some potential, but only time will tell, as it hasn't been in mainstream use very long (less than 40 years) where sawdust has been used for over 200 years and the results have been positive if the wall is aloud to have complete permeability, and a dry heat source in colder weather periods. In most modern applications the "house wrapps" and "vapor barriers" eventually fail and cause interstitial moisture build up that goes unnoticed for too long. Any moisture in cellulose nocks its r value down to near zero.

Another consideration is I don't think of "new paper" as a "natural building material" no more so than I do "mineral wools," which have much better performance and history. These two materials are in the recycled or repurposed realm of insulations...not "natural." Of cellulose or mineral wool I always recommend MW over Cellulose for a number of reasons, but moisture resistance is the main one. I can take a board or batt of mineral wool and place it in a tank of water overnight and it is still in good enough shape the next day to place in a wall void....I would never do this with cellulose and even dislike the many "wet applications" that many contractors use to apply it.

As you get into this "r value" thing you will soon learn about its reciprocal..."u-value." This is what the U.K tends to use instead of r value because it is a better indicator of "thermal mass" and its storage capacity. Log cabins have a low r value, yet have a better u-value of a 2x wall...this is what makes them work. When you combine a natural system like log or "Kubbhus" architecture with other natural insulative materials like sawdust, or light straw clay systems, mass wall design, and "thermal break" layers, you can achieve "net zero" efficiencies.

Even among the "experts" there is debate and a great deal to learn about these two measurement systems and how they actually apply. I could probably safely state that we known less than we actually fully understand, and there is still countless amounts of misinformation and misunderstanding...Especially when it come to traditional and natural insulations, how they work, or how traditional and/or natural building systems function. We know historically that they did work, and for millenia in some cases. It hasn't been till the last 50 years that issues have been created and most of those have grown out of ignorance and/or application of modern methods that aren't yet fully understood themselves...

I think, and have observed, that natural and traditional systems can and do work much better than anything we have come up with in the last 50 years...

Regards,

j
 
Troy Rhodes
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Cellulose has been in use since the 1950's.

Settling and moisture control are both important, but not insurmountable concerns. Any loose fill insulation, like sawdust, will have similar settling issues.

 
Jay C. White Cloud
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Sorry Troy...

My comments about cellulose (a.k.a. newspaper) were not directed to your application of them at all. I have no idea what application method you have employed and it may (or may not) be one of the more potentially durable methods.

We should clarify some facts that when most speak of "cellulose insulation" today they are, indeed, speaking of a post consumer byproducts of at least 75% old newsprint. Historically "cellulose insulation" goes back over 1000 years, but these forms and applications include: straw, cotton, sawdust, cattail down, paper, paper plasters, et al. The historic forms are broad in both material, as well as means and methods of application. Straw bale is technically a form of cellulose insulation.

However...as I stated before...
it hasn't been in mainstream use very long (less than 40 years)
and this is actually a conservative estimate. It's actual mainstream and common use did not really start until the mid 1980's, yes it was used before then...but not commonly or in the formats we know it today. Even if it was 50 years, this does not give us statistically a viable history to extrapolate solid understanding. This alone, besides the questionable "wet applications," have given us a very limited window of historical record of performance and overall durability.

The preliminary evidence strongly suggests, just like the more natural forms of cellulose (i.e. straw bale, sawdust, hemp, etc) that absolutely no vapor barriers nor other "condensing surfaces" (Tyvek, or related materials) should every be part of the thermal envelope system that uses these materials, especially in "super insulated or mass wall designs." Having witnessed numerous fails in such wall systems myself, I tend to agree with these evidentiary findings. This is one of the primary reasons I now only support and recommend "breathable" and "draft proof" wall systems, and never "air tight" modalities.

One application of "actual" paper based insulation like recycle new print that I love and have used for over 40 years (very rare here in the states) is true "paper plaster," which has a history in Asia going back close to 1000 years. These esthetically are usually only 3mm to 5mm in current use but can be layered up to heavier thicknesses. These provide not only deep color depth but also a textile warm and acoustic softening not found in other interior treatments. In Asia, the Middle East and Eastern Europe today they are quite popular, yet have not gained a market interest here in North America...yet... Here they must be mixed and colored from scratch which doesn't make them cost effective for most building professionals.

Regards,

j
 
Troy Rhodes
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No harm, no foul.

I agree that wet blown cellulose is not a guarantee of failure, but almost.

I install it dry, and (either) blown to densities where it will not settle any further, or blow it, and then blow it again a year later after 98% of the settling has already occurred.

It is blown into an open wall cavity between an inner wall frame, and an outer wall frame. Using this method virtually guarantees that there will be no voids. We heat with wood, and the house (generally) runs at a slight negative pressure relative to the outside.


It's a tool. It can be used well, or poorly. If you don't understand the behavior of water vapor and air movement through a house, you will have problems.
There are train wreck examples where moisture control was thoughtless and counterproductive and had to be torn down after just a few years due to mold and rot problems.


But there are very few tools and techniques that can be applied without attention to detail and a good understanding of the many factors that can bring success or failure.


There are trainwreck examples of straw bale homes, and underground homes, and cob homes, and high mass adobe homes, and passive solar homes, and geodesic homes, and homes that depend on high tech heat pumps that were installed badly.

Where I gained my experience, in Iowa and Ontario and Michigan, dry blown cellulose has been a useful tool for me.

Finest regards,

troy

 
William Bronson
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@ J. C. White Cloud :
Could you give me alternative search terms for "paper plaster "?
I am very interested, but I am not finding the kind if thing you have described. I have a first floor that is plaster over brick, adding something insulating to the interior seems promising.
 
Troy Rhodes
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It's similar to paper mache.


troy
 
Jay C. White Cloud
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Hey William B.,

Sorry about that...poor form on my part...

I too get frustrated when someone shares "partial information" and then you drive yourself nutty trying to figure out the details...

It is something like paper mache...kind'a...as Troy has suggested, but not really quite the same....or...perhaps I should say more refined and encompassing. I am still learning more about it myself all the time, and I have been messing with it for over 40 years when I learned it from a elder care giver from Korea while she taught my mother.

There are several "paper craft traditions" in Middle Eastern and Asian Culture. Japanese culture has some of the oldest sustained traditions and refined paper arts in the world today. "Paper plaster" or what is more often translated into English as "liquid silk plaster," which makes sense because the better papers are silk or pure cotton, flax, hemp, or something similar to papiris. I have been trying to secure a "dealership" with several companies out of China and Russia for about ten years. Now they had one in Atlanta, GA, but that seemed to have ended for them (very bad English and advertising.) Now there is a distributor...I think, in Canada. The price point is just to high for most projects and I still just make my own when I must, but I am currently in correspondence with several manufactures.

Hope that helped,

j
 
Henry Tiver
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WOW! You gave me so much information, my head is spinning. I think I'll just buy my wife a good coat.
 
William Bronson
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Jay C. White Cloud wrote:Hey William B.,

Sorry about that...poor form on my part...

I too get frustrated when someone shares "partial information" and then you drive yourself nutty trying to figure out the details...




Brother, you are always generous with your knowledge, no reason to apologize! Thank you yet again.
 
William Bronson
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About celuouse or sawdust or other loose fill, when used in walls , what do they "sit" on?
Are they in direct contact with the foundation?
In a standard stud wall, I suppose the fill sits on top of the floor plate, when the wall is a foot thick, is the cavity floored with something?
I am wondering be cause of wicking moisture, from what ever the material is .
Forgive me if this is foolish concern...
 
Jay C. White Cloud
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Hi William B.

The "teacher" in me can't help it...There is no such thing as "floosh" in any honest request for information...

So, I think I know what you are asking and considering that your prospective is probably more rooted in "modern methods" than traditional vernaculars it makes perfect sense. This is a major problem in many modern designs as architects and contractors have moved too far away from "good practices" in architecture and way into "convenience, "I think" methods, and speed for profit motivations. This has left us with many issues, like no over hangs on roofs, and houses that site at grade level or even below.

I won't place a structure I facilitate closer than 600 mm to finished grade, unless specifically designed for such contact. Then the materials are all moisture tolerant (e.g. stone, brick, etc.) Traditional methods usually follow the same format and logic in design. This is the reason that a sawdust filled void would not be anywhere near the finished grade or "splash zone."

Hope that makes sense...

Regards,

j
 
Andrew Parker
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Rice hulls make good insulation, if you are near a source (they are relatively heavy in the quantities needed and they don't compact well for shipping), but you need about 12." Naturally foamy plants, like cattail leaves (not the fluff, in this case) and tule stalks, can be used as thatch, woven or sewn into mats (historically used throughout North America by Native Americans for insulation and mattresses) or pressed into panels (with a binding agent), or, chopped and blown into cavities (pre-treated similar to cellulose). I have no idea of R-values, offhand.
 
Troy Rhodes
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In my shop, the wall sits on a floating slab. The slab is isolated from the fill/sand/gravel/soil by 2" of high density styrofoam, so that breaks moisture creep up through the slab.

I laid 1/4" plywood in the void between the inner and outer base plates, so the cellulose never touches the cement, and under the plywood is 6 mil polyethylene.

Yeah, roof overhangs drive me crazy--when they are too small.

I built a mower/tiller shed, and it got 2' overhangs too.


Yes, it is shocking to see a building, especially a residence, that does not have positive drainage (ie a good slope) away from the house.
 
Terry Ruth
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R-Value has been by far the single most misleading metric of insulation performance to date, more so in today's modern building's insulation as Jay and Bill pointed out. If your good technically check out the "Breathable Walls" thread and the three different modes of moisture transport, Permeability, Absorption/Desorption (or drying speeds based on water content of air or Relative Humidity) Equilibrium Moisture Content (EMC) is part of this metric), and Capillary absorption/desorption. Most modern world manufactures do not disclose this data.

Two schools are highly insulated envelopes or high mass, or hybrids. Other two are loose fill in cavities such as fiberglass, cellulose, mineral wool.....Because FG is very loose and test have shown it's r-value drops significantly when moist "convective loops" or "air barries" enter the cavity and circulated in and out of it, a new school was developed to "air seal" the cavity to stop the loops. Cellulose industry took the test further and determined that dense pack prevented the loops, eliminating or reducing the need for air sealing or the need for a drying direction, proposes sealed vaulted roofs and walls I do not agree with. As you pack in insulation (I think the two values are 3 and 5 PCF if I remember right) the R-Value goes down, bridging goes up, drying speeds down, If drying does not occur in less than 48 hours mold can develop IF there is a food source (plastic interface would me one, most glues in laminated plywood, so are the admixes in most concrete).. So it is VERY dependent on the installer to verify density and mating materials. I think 3 PCF is better IF it is verified and does not settle to create air barriers which lower effective or whole wall r-values. Many manufactures list nominal r-values from lab test that mislead. Cellulose does dry fast if it has a "Breathable" assemble, it has a perm rating of ~23....Wood across the grain is slow, along fast same with hemp, flax, wool fast tightly pack good at reducing loops high perm 41, very low MC....plywood slow, plastic and foam barrier n/a off the charts slow and wrong in most cases.

Mass designs incorporate a binder that binds to most everything it touches such as clay-slip, limecretes, mag-cretes, etc....combined with hemp, straw, wood chips, that create air pockets or r-values and hygroscopic properties, dry very fast, capillary breaks such as neoprene under sills are not needed, make excellent cast in place over studs (double is good to have something to nail to for cabinets, etc, timbers, at the surface) but it can get pricey, lots of mortar mixing and shoveling in. Most have r-values in the range of 1.5/inch to 3.5/inch such as hemp-crete (12 inch) u-value test out of the UK show. Strawbale is up there with clay or lime plasters, especially to the interior. Again, highly misleading since "dynamic mass effect" out performs r-value in most cases, especially at managing moisture it's value is not reduced by. It can drop heating and cooling loads by 2/3 especially in passive solar designs to net zero as Jay said, So can Rammed Earth, most insulation's cannot unless there is large air seal effort to blower door test below .6 ACH Passivhaus. With mass two systems are resonating at different frequencies if you will, the outer surface and inner......Most high insulation design do not have such a assembly property that functions at depths from 1-3 in from both surfaces, storing-releasing heat and moisture, but never bridge if designed right. Drying occurs in both directions from radiant heat that constantly changes small air per hour but does not effect heating and cooling loads or loose it to the outside.


Cellulose - depends on the configuration. Straw tubes behave different than packed cellulose, or solid wood tube grains depending on directions, or bound hemp, straw, chips, etc.

My .02
 
Jay C. White Cloud
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Terry...simply awesome..!!

The above post was so good...matter of fact...I am emailing you about it, because I know about 80% of readers eyes glazed over after the first three sentences and probably only can digest about 20% of what you just wrote (but I know...you know that...)

Fellow readers, Terry's above post is so good that I am going to try my best to break down certain parts so we can all digest the "meal of information" that it is. This is some of the most important issues in the current topics about insulation...Some of these issues, and challenges have million dollar price tags attached to them because manufactures and insulation contractors don't really want consumers to begin to realize the "hype" and misinformation they have been feeding us all these years. Simply put...insulation factors (i.e. r/u values) is very poorly tested and understood science and individuals like Terry are just now starting to shed some actual "real" light on what is known (that is very little) and what is not known (which is a whole bunch.)

Thank you so much for posting that!

Talk soon!

j
 
William Bronson
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J,I am looking forward to your translation.
I like the layers of communication that happen here.
 
Terry Ruth
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Guys and Gals, I'm super busy right now developing big land putting these designs to builds and I'm not as good of a writer. I try and get out here in my spare time. I suggest you hire Jay or Bill for your next project they understand everything I posted and more.
 
I agree. Here's the link: http://stoves2.com
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