Dry stack. What type of block is best?

I'm about to order my block for a small building I'm dry-stacking and I'm wondering if I have to use the square corner block instead of the regular block. All the pictures on dry-stacked.com show the square corner blocks but they are a little harder to obtain than the regulars.

Hmmm...??...OPC block??...

I am not trying to dissuade, nevertheless, as a permaculture group...opc is usually not encouraged because of the environmental impact of the industry and the general poor nature of modern concretes in general. As a professional builder in the natural-traditional modalities as well as mainstream methods, I have seen a number of these "quick wall" systems fail. They seem simple because they are simple, and perhaps that is their downfall for enduring architecture.


Regards,

j

I don't think those houses would even pass building consent standards here! they'd tumble down like the trhee little piggies being visited by Mr Wolf in the first good jolt!
Mind you, living on the ring of fire is a bit different from well inland on the continential crust, but I wouldn't build a block house without mortar or binder between all the blocks as well as slathered on the outside.

PLUS, the description of the exterior/interior binder sounds like an impermeable barrier, so the house would be sealed and hold all it's moisture in, you could run into future mould and mildew problems.

Good brick and block is porous, the house can breathe, sealed up? well have you ever gotten frisky in the back seat of a car? see what the windows do?

Rhys Firth wrote:
Mind you, living on the ring of fire is a bit different from well inland on the continential crust, but I wouldn't build a block house without mortar or binder between all the blocks as well as slathered on the outside.

Now now, please google "Machu Pichu stonework" and click on the images. Wow!

SOLID stone in blocks weighing tons is a bit different than a thin one wide stack of breeze blocks.

Rhys Firth wrote:I don't think those houses would even pass building consent standards here!

Actually, this techinque is sanctioned under the IBC (I don't have the chapter refernce with me at work.) Dry stack CMU is permittable, with the constrained that no more than 200 square feet without reinforcement or piller built into the wall. Of course, a bond beam at the top is used which locks it all togther fairly well. As far as seismic considerations, you may be right. However, side by side in a seismic zone, I would still have more confidence in CMU construction than stick built.

To answer Philips question - No. You do not need to use corner blocks. I have seen some information on "dry-stacked's " technique and I believe he alternates the orientation of each course at the corner. I don't believe he actually advocates corner blocks. In his calculator as I recall he shows the compensation for the variation (about a 1/4 of inch as I recall) to compensate for the alternating courses final length.

Jack Edmondson wrote:To answer Philips question - No. You do not need to use corner blocks. I have seen some information on "dry-stacked's " technique and I believe he alternates the orientation of each course at the corner. I don't believe he actually advocates corner blocks. In his calculator as I recall he shows the compensation for the variation (about a 1/4 of inch as I recall) to compensate for the alternating courses final length.

Thanks for the reply Jack! So just to confirm, you have seen dry-stack construction using regular block? Of course corner block for the corners etc but not in between the corners? I cannot logically think of any strength benefit from using only corner block...

I have seen the calculator things as well. Ill make sure to figure for that.

Also I have another question. What would happen if I mortared my first course of block onto a level rubble trench of gravel? (no concrete footer).

Rhys Firth wrote:PLUS, the description of the exterior/interior binder sounds like an impermeable barrier, so the house would be sealed and hold all it's moisture in, you could run into future mould and mildew problems.

The exterior/interior binder= SBC is in fact impermeable. My earthen floor will help mitigate moisture and my ceiling will be wood, cellulose insulation then vented metal roofing. Also an exhaust fan by bathroom area. So I'm not expecting mold or excessive moisture to be an issue.

Wait a sec folks.
Surface bonded, dry stacked block construction is stronger and more flexible than block and mortar construction. Especially if the cores have rebar and are filled.

Mortar between blocks does the same thing as perfectly cut stone. Just makes a full joint but it doesn't "glue" them together. It's weaker when a deflection load is applied.

Surface bonding makes a kind of composite sandwich, sort of like a door or an "I" beam. Rigid skins on either side of a stiff space. Fibers in the bonding compound span the space over the joints in the blocks and don't just rely on the weight of the structure to hold it all together. Couple that with filled cores (pillars) and you can have much stronger wall than block and mortar.

Jay C. White Cloud wrote:Hmmm...??...OPC block??...

I am not trying to dissuade, nevertheless, as a permaculture group...opc is usually not encouraged because of the environmental impact of the industry and the general poor nature of modern concretes in general. As a professional builder in the natural-traditional modalities as well as mainstream methods, I have seen a number of these "quick wall" systems fail. They seem simple because they are simple, and perhaps that is their downfall for enduring architecture.


Regards,

j

Yes, OPC... I guess I have a slightly different opinion tho we do agree on a lot of points about OPC. I want to use as little as possible mainly because it's not cheap, not because it uses lots energy to produce. I don't view CO2 as pollution for the most part. Trees off gas CO2 when they rot on the forest floor. I don't care how much CO2 my house puts into the atmosphere. I do care how long it lasts, how much it costs and how it looks and I do care if the materials I use for my house cause real pollution or harm to the environment. Conventional studs are grown in spruce mono-cultures. I don't like those... Mono-cultures are not good for the environment. Industry creates chemical byproducts, that is real pollution.

If we had access to the "good" cement used by Romans etc would you use it? I would! Long lasting, strong, looks great. Yeah It might be expensive but wouldn't it be worth it? Yeah it would take a lot of heat to make, but wouldn't it be worth it?

My opc blocks and SBC are by no means up to the Romans standard but hey it's the best Iv'e got for my precise situation. It will last a long time, it will look good, it will be quick to build, it will fit into my land layout and it will be cheapish...

Hi Roy,

We agree technically on many points...however....

Surface bonded, dry stacked block construction is stronger and more flexible than block and mortar construction.

Agreed...nevertheless...block and mortar CMU are a pretty low bar, both architecturally and environmentally...

Especially if the cores have rebar and are filled.

Again...I agree from a structural wall diaphragm perspective.

Mortar between blocks does the same thing as perfectly cut stone. Just makes a full joint but it doesn't "glue" them together. It's weaker when a deflection load is applied.

Here we will have to differ, and for the benefit of the readers, there is a huge difference between CMU and stone...just about any way you "split it." The mass, and cohesive friction of fitted stone block as referenced is dramatically stronger that any CMU...mortared or surface bonded.

Surface bonding makes a kind of composite sandwich, sort of like a door or an "I" beam. Rigid skins on either side of a stiff space. Fibers in the bonding compound span the space over the joints in the blocks and don't just rely on the weight of the structure to hold it all together. Couple that with filled cores (pillars) and you can have much stronger wall than block and mortar.

I agree again with this...however, the long term track record of CMU surface mounting modalities is very limited at best...and...we still have the matter of the environmental track record of the industries behind it. I would also suggest that there is a great degree of "assumption" in the methods material assembly, as any degradation from age or tectonic fatigue greatly compromises the entire system.

>>>

Hi Philip,

Not all CO2 production is the same...no where near the same... Biochemically the production of biologically active COS emissions is drastically different than those produced by big industry, and as a permaculturalist (and permaculture site) we no more promote "industry CO2 production" than we do pesticides, and monoculture forests. Everyone should care and be concerned with not only their individual CO2 production but also how industries affect this planet...

Industry creates chemical byproducts, that is real pollution.

Yes it does...in deed! And, the OPC industry is one of the largest there is and backs many more along the way...

If we had access to the "good" cement used by Romans etc would you use it?

Absolutely...and...we do have it. This yet again "reinvented wheel" of alleged technology that is "geopolymer chemistry" is nothing more than a form of "roman cement," in some of its permutations. We also still have "natural cements" (a.k.a. Rosendale Cement) owned and operated by Mike Edison a friend and colleague, as well as someone inside the "OPC industry that knows full well its many ills and plagues...and he wants to see it changed.

I would! Long lasting, strong, looks great. Yeah It might be expensive but wouldn't it be worth it? Yeah it would take a lot of heat to make, but wouldn't it be worth it?

You lost me here...?? If this is about "Roman Cement" I must suggest more research. RC, NC, and GPC are all very low environmental impacts compared to what the OPC industry is pumping into the Air, ground and water supplies.

My opc blocks and SBC are by no means up to the Romans standard but hey it's the best Iv'e got for my precise situation. It will last a long time, it will look good, it will be quick to build, it will fit into my land layout and it will be cheapish...

I have to question this mainly because of the nature of this forum and readers that I know follow my writing. OPC in any form has to be confronted and avoided whenever possible. It does not "last a long time," it appearance is a subjective thing as most folks I deal with abhor its esthetics; it speed of construction is an illusion in many ways if the "big picture" is looked at; and as for cost...well I will give you that if all that is considered is the fiscal aspect...Yet, there is so much more in "valuation" than just money...

Philip Nafziger wrote:

If we had access to the "good" cement used by Romans etc would you use it? I would! Long lasting, strong, looks great. Yeah It might be expensive but wouldn't it be worth it? Yeah it would take a lot of heat to make, but wouldn't it be worth it?

My opc blocks and SBC are by no means up to the Romans standard but hey it's the best Iv'e got for my precise situation. It will last a long time, it will look good, it will be quick to build, it will fit into my land layout and it will be cheapish...

We moderns have of course been able to discern what is in the great cements of the Romans and many others through high tech methods like thin section analysis, XRD, XRF, SEM and chemical analyses. What we modern people haven't been able to reproduce is the methods employed.

There is a lot more finesse that must be employed with more natural products like lime based cements, but once learned, the whole world opens up and you will never want to use another OPC product. The lime based cements are more flexible and softer, this makes them stronger in application, just as a wet twig is flexible and strong and a dry one is brittle and strong. The brittle nature of OPC based concrete and the products from it are prone to cracking. I have repaired 2 of these and this convinced me of the inferior nature of this building system.

I would suggest that you design your building with natural materials; you will gain valuable experience that will influence everything you build or live in for the rest of your life.

roman pantheon

Take a look at this tornado site I went to study last June 2014. The old 100 year mortared CMU, brick, mass, were the only buildings to somewhat survive the twin EF-4s reaching speeds of 200+ miles per hour that combined to completely destroy all the light framed wood in this small town of Pilger, NE. Look out basements survived, some storm shelters you were fine in if you made it. A little five year old girl named "Cali" unfortunately died in a mobile home, her name on the library still standing. An elder too. Many injured. This happens every year in the mid-west and they rebuild with the same old crap studs that kill. 300 miles east a church built of strawbale in early 1900's Author, NE still stands after seeing EF5 and some of the nastyest storms in the country. The biggest threat are the flying studs and debris (metal roofs and barns, semi trailers, cars, etc) some of which nothing will stop, but the biggest threat is the wood, known and proven by Texas Tech University to kill. It will not penetrate 4" of CMU or concrete at 150-200 projectile speeds in a test on their site, light framed wall get demolished.


Video footage:

More PICS

More PICS

Two semi trailers carried and flipped over..

The issue with OPC is not only that is takes twice as much heat than lime and MGO, the ad mixes also outgass to IAQ causing health issues you can find reports on the internet. They have been trying to fix OPC with additives for decades now to have the properties of natural cements since it is cheap. I'm glad Premier has started to sell raw light burnt MGO in the USA. Many countries have nothing to do with OPC.

To me, it is sad kids or anyone has to die in a home where they should be safe. The cost of the mobile home $40-80,000 + these days Cali died in could have went into strawbale, cob, ceb, adobe, CMU, rammed earth, etc, that can take the winds and debri, other than roof. Hurricane ties, dome roofs, radial roof, pressure relieve, helps. One day we hope to mobilize to these area to stop people from putting more light frame up.

After Fema shows up the stick builders swarm in to tap into insurance money. No natural builders show up to educate these poor people. I'm always amazed how mother nature stikes the poorest communities with mobile homes. Go figure!

Bill Bradbury wrote:We moderns have of course been able to discern what is in the great cements of the Romans and many others through high tech methods like thin section analysis, XRD, XRF, SEM and chemical analyses. What we modern people haven't been able to reproduce is the methods employed.

There is a lot more finesse that must be employed with more natural products like lime based cements, but once learned, the whole world opens up and you will never want to use another OPC product. The lime based cements are more flexible and softer, this makes them stronger in application, just as a wet twig is flexible and strong and a dry one is brittle and strong. The brittle nature of OPC based concrete and the products from it are prone to cracking. I have repaired 2 of these and this convinced me of the inferior nature of this building system.

I would suggest that you design your building with natural materials; you will gain valuable experience that will influence everything you build or live in for the rest of your life.

roman pantheon

Very informative, thank you Bill. I especially like your twig example. So are you saying ancient Roman concrete is essentially NHL? Have you any experience with Chris Magwood and what he is doing here? Is lime with added pozzolan as good as NHL from France? Thoughts on that? I would love to use lime more but if I have to get it from France that kinda defeats a lot of the purpose of natural building.

As far as repairing two CMU buildings: just because they needed repairs doesn't mean that it is a faulty system but perhaps just a faulty construction of that system? I've seen CMU walls 100 ft long and 30 ft high that have nary a crack in them. I've also seen CMU walls 10 ft long and 3 ft high that have cracked to rubble etc.

I research the Pantheon. VERY cool. Puts modern construction to shame with our pitiful reinforced concrete.

Jay C. White Cloud wrote:Hi Philip,

Not all CO2 production is the same...no where near the same... Biochemically the production of biologically active COS emissions is drastically different than those produced by big industry, and as a permaculturalist (and permaculture site) we no more promote "industry CO2 production" than we do pesticides, and monoculture forests. Everyone should care and be concerned with not only their individual CO2 production but also how industries affect this planet...

Industry creates chemical byproducts, that is real pollution.

Yes it does...in deed! And, the OPC industry is one of the largest there is and backs many more along the way...

Ok so what you're saying is that the concrete industry puts more into the atmosphere than just co2? If so, what exactly, and what exactly is the difference between COS and CO2?

I personally believe that carbon emissions do not effect the climate in a serious way. I do believe that the ice caps are much smaller and still shrinking but no one talks about the natural cycles of the sun and earth. This doesn't mean I advocate big industry it's just that I can't get on to anyone for simply releasing plain CO2 into the atmosphere.

Jay C. White Cloud wrote:

If we had access to the "good" cement used by Romans etc would you use it?

Absolutely...and...we do have it. This yet again "reinvented wheel" of alleged technology that is "geopolymer chemistry" is nothing more than a form of "roman cement," in some of its permutations. We also still have "natural cements" (a.k.a. Rosendale Cement) owned and operated by Mike Edison a friend and colleague, as well as someone inside the "OPC industry that knows full well its many ills and plagues...and he wants to see it changed.

I would! Long lasting, strong, looks great. Yeah It might be expensive but wouldn't it be worth it? Yeah it would take a lot of heat to make, but wouldn't it be worth it?

You lost me here...?? If this is about "Roman Cement" I must suggest more research. RC, NC, and GPC are all very low environmental impacts compared to what the OPC industry is pumping into the Air, ground and water supplies.

I was saying that I would use roman concrete if it were available. Which I'm learning is! More research on my part to follow...

Jay C. White Cloud wrote:

My opc blocks and SBC are by no means up to the Romans standard but hey it's the best Iv'e got for my precise situation. It will last a long time, it will look good, it will be quick to build, it will fit into my land layout and it will be cheapish...

I have to question this mainly because of the nature of this forum and readers that I know follow my writing. OPC in any form has to be confronted and avoided whenever possible. It does not "last a long time," it appearance is a subjective thing as most folks I deal with abhor its esthetics; it speed of construction is an illusion in many ways if the "big picture" is looked at; and as for cost...well I will give you that if all that is considered is the fiscal aspect...Yet, there is so much more in "valuation" than just money...

At this point, my contract for my apartment is up in April and I need a building that is strong, quick to put up, able to be built with readily available materials, and workable on a steep hillside. I'm sure you would be able to come up with a natural design to fit my needs but I'm think my brain is to far committed to my current design to change again.

Philip Nafziger wrote:
The exterior/interior binder= SBC is in fact impermeable. My earthen floor will help mitigate moisture and my ceiling will be wood, cellulose insulation then vented metal roofing. Also an exhaust fan by bathroom area. So I'm not expecting mold or excessive moisture to be an issue.

I have to say Phillip, in my experience, this is a recipe for trouble. Check this thread Breathable-Walls

If you go this non-breathing route, at least install humidistats on the exhaust fans.

We are installing Roman plaster on our B&B project, lime and pumice/ash. The Roman concrete recipe used pumice/ash as well as crushed bricks and many other pozzolana. It is the pozzolan effect that gives the Roman concrete the edge over other lime based concretes and allowed them to efficiently build these megaliths.

The quality of lime that I seldom hear about is the quality of energetic resonance in the crystalline structure of limestone. This is why most of the great religious structures of the world are built of limestone or plastered with lime. When limestone is heated to OPC temps, the crystalline structure is destroyed. OPC uses Calcium Silicate Hydrate to glue the aggregate together, where as lime returns to limestone and it's original crystalline matrix, making a softer more durable building material that still breathes and resonates not only to sound waves, but other more subtle energetic influences as well.

Hey Bill remember this thread using block with SBC skins, can't figure out why the walls are sweating? Answer: Zero perm SBC can't breathe/dry. https://permies.com/t/44599/wofati-earth-berm/solve-sweating-South-Wall

Best made block out there is Durisol or Faswall, center concrete fill. It is made of a low density wood clay cement, very small OPC (10%) that gets neutralized by clay. It has huge properties shown by builds and testing. If you are looking for fast construction blocks, they lock together, ICFs no foam or SBC toxic barriers. Light low shipping cost.

Dead or light burnt magnesium, phosphates and chlorides, make great cements, boards, sprays, etc.

From what I gather from pure NHL manufactures is they think these limes are superior in the non-altered state, no pozollans or artificial chemistry needed to create the class of AHLs needing a chemist for each build, so they bag NHL 2, 3.5, 5 depending on needs (set times and strengths). I guess your always welcome to experiment with add-mixes. Our limes in the US are different, Type S and N which are cheap here in the states, NHL very expensive, OPC VERY cheap. I think there are ways to use OPC IF you know what your are doing so they do not off gas....As far as the atmosphere that is debatable I do not know I am no environmentalist I struggle just keeping the environment inside home clean You can spend ALOT of money doing it all natural since the materials are not as available and in some cases the labor is cost is either not known with a learning curve or high due to lots of work mixing, casting, etc....Alot to consider when making a choice. If I have ship bags of roman cement or NHLs, pozzolans, in from Europe or Rome how am I doing any better than buying a local bag of OPC polluting the atmosphere? I think the term is "Embodied Energy" that just does not include CO2 production.

AAC block with a clay or lime plaster would be a good choice...Some light blocks are rated at close to 3000 PSI compression, but the OPC goes up unless you use mag cements which has 7 up to 40 times more compression strength and other higher properties but then your into shipping probably.

Philip Nafziger wrote:
So are you saying ancient Roman concrete is essentially NHL?

No, I'm saying that some pozzolan are better than others and technique matters more than anything. Roman concrete is far more diverse than even modern concrete, so we'd just be generalizing.

Philip Nafziger wrote:
Have you any experience with Chris Magwood and what he is doing here?

I don't know Chris but the project you referenced looks really great. I have tried quite a few similar recipes, but not that one.

Philip Nafziger wrote:
Is lime with added pozzolan as good as NHL from France? Thoughts on that?

The stuff I'm getting fromlimestrongis the best I've ever tried.

Philip Nafziger wrote:
I would love to use lime more but if I have to get it from France that kinda defeats a lot of the purpose of natural building.

I couldn't agree more, which is another reason that I use what I do; the mine is only 45 miles away.

Philip Nafziger wrote:
As far as repairing two CMU buildings: just because they needed repairs doesn't mean that it is a faulty system but perhaps just a faulty construction of that system? I've seen CMU walls 100 ft long and 30 ft high that have nary a crack in them. I've also seen CMU walls 10 ft long and 3 ft high that have cracked to rubble etc.

Yes, they can be well built and last a long time, at least by modern standards.

Philip Nafziger wrote:
I research the Pantheon. VERY cool. Puts modern construction to shame with our pitiful reinforced concrete.

The real takeaway here is that breathable, flexible, dynamic buildings enliven the spirit and far outlast their creators and sometimes even their creators' culture.

And since I'm already up here on my soap box; hot CO2 from ignition sources etc. rises up into the atmosphere and causes more problems than cool CO2 which stays lower down and is utilized by plants.

Hello Phillip N., et al,

I know I am going to "miss something" of your questions and/or comments, yet believe others have probably addressed them well enough to carry the conversation forward. I do have some highlight points to address that seem worth clarifying and stressing...

Philip Nafziger wrote:Have you any experience with Chris Magwood and what he is doing here?

No, not directly with Chris's work, but indirect correspondence and familiarity with the methods, materials and, means. A wonderful contemporary example of lime use that is becoming more common (fortunately) around the globe. Europe, the Middle East and Asia is way ahead of us in understanding and utilizing these modalities.

Philip Nafziger wrote:Is lime with added pozzolan as good as NHL from France? Thoughts on that?

I am not sure of this focus on France as the only source??

We have NHL lime stone deposits here in the North America, and not all NHL lime has to come from France. Just a little research can locate vendors much closer as Bill has shared. To the other point...pozzolan additives and the according pozzolanic reactions that are initiated don't render a "better" material matrix...per se...but different and for different applications. Could a simple "homemade" hot lime mix as is done in Mexico and South America with lime stone or Seashells, with a locally sourced pozzolan behave as well as a NHL from France? Probably, in a give germane application.

Philip Nafziger wrote:As far as repairing two CMU buildings: just because they needed repairs doesn't mean that it is a faulty system but perhaps just a faulty construction of that system? I've seen CMU walls 100 ft long and 30 ft high that have nary a crack in them. I've also seen CMU walls 10 ft long and 3 ft high that have cracked to rubble etc.

I did not mean to suggest that a good modern Mason, applying the proper means, methods and materials as warranted by "quick wall" and CMU application could not build a solid wall. I am sure they could. We (I) spoke to the environmental impact of such methods, and their long term durability and applicability...especially as it applies to the methods promoted by those claiming interest in following Permaculture practices...

As for CO2, heavy metals, and other dioxides that industry produces that affects weather change, I would not address in this conversation, as it turns "political" and lacking in good science understanding too quickly to even be a productive discourse within its own context as a conversation...in most cases. What I say to folks that bring it up is usually a series of questions.

Has the questioner of this topic read any of the foundational research on biome impact, meteorological shifting, and other related research that examines climate and climate shifting?

Do they fully or even partially understand its fundamental science, context and what this research examines, or the very possible projected theorems behind it?

Have they direct knowledge through site visitation and examination of locations that are seeing a strong impact by climate change?

Without just these three simply fundamental consideration, it is virtually impossible to engage in a discussion of..."what"...climate change is...Let alone its underlying triggers and causal elements. Very few I speak with that dismiss this issue have any direct experience or examination of biome, nor a solid enough science background to fully engage...just like many of our political leader "do not" have a solid foundation in the sciences...yet...seem to have very strong views about it and set policy from these "limited views," which also in most cases are the views of there primary supports in industry...

What I usually close such short conversations with, is that one does not have to agree on the "causation" to understand that climate is shifting and that large industry and there massive pollutants do not push this issue in a healthing direction, no more than our individual contributions facilitate a positive effect. We are all the issue and should take ownership of every little bit we can and not deflect that what each of us do doesn't matter. Remember the "butterfly effect" which still is not fully understood, yet can be partially understood by simply throwing a pebble in a still pond...

Lets all stay away from this topic...At least here, as it would only become a distraction...

Philip Nafziger wrote:...I need a building that is strong, quick to put up, able to be built with readily available materials, and workable on a steep hillside. I'm sure you would be able to come up with a natural design to fit my needs but I'm think my brain is to far committed to my current design to change again...

STEEP HILLSIDE...

Sorry, Philip...as soone as the above description registered...my PE training kicked in. This is absolutely the last place I would ever specify for a client any type of masonry structure...traditional, natural or modern. Not unless there is solid and well established bedrock without mitigating tectonic activity of any kind. If there wasn't bedrock, and the area could even marginally be exposed to high winds and seismic activity, then CMU would never enter the material stream of the project at all. Nor is such a location ever...easy...per se...to build in.

If this was an "historical project" then I would look to the vernacular for the region and the vintage methods employed. At no time, in such a location could masonary be called "strong, quick or workable," in most methods. Stone could very well work, but the effort and carving involved is well outside the context of a DIYer, and the only "easily facilitate" structures for such location are some form of "stilt architecture" and/or some "fossorial methods." None I would equate with "quick" or easy.

My intent is never to affect someone's "committed" views, but only to share information as I know it, and the experience of 40 plus years in and around this complex field.

Thank you all for your very interesting and VERY complex bits of information.

J. My site does in fact have bedrock about 3ft below the surface if that is of any condolence.

Coming along years later.

OPC - Ordinary Portland Cement

Above mentions two specific products Durisol and Faswall.  Durisol "rebranded" and is now known as Nexcem.  Green Building Advisor has some threads between when this thread was started and my comments today, which mentions broken links to technical information on the Nexcem website.  They are _still_ broken a year or more later.  They don't seem to want to fix their website.

Acronyms are often a pain.  Two engineers that both had experience with PCBs got to talking.  The one engineer couldn't see why PCBs were considered such a problem - he had been working with Printed Circuit Boards for years without any problems at all.  The other engineer was talking about Poly-Chlorinated Biphenyls.

I think I need to go read about earthbags.

Bill Bradbury wrote:
The stuff I'm getting fromlimestrongis the best I've ever tried.

Is that BioLime now?  https://biolime.com/product/biolime-finish/  $80-110 55lb

Tim used the rock at Wheaton Labs to build this dry stack Moon Gate. They built a circular drum from wood to hold the rock in place as they built the "window". Would this work for the walls of a structure? It appears pretty stout.