The Story of the Magic Insulation and the Steel Boxes

2 Sep

Addendum: Sept 3, 2010:

A 7.4 magnitude Earthquake struck just miles west of Christchurch, NZ  at just after 4:35am this morning.

Many who read this blog know that we have many, many friends, in New Zealand.

Please know that our hearts and prayers are with you, as you begin to recover from the earthquake.

If there is anything that we can do to assist you, know that you have but to ask.

Ronin.

And now back to our regularly scheduled program:

It must be that time of year again…

I don’t know if it’s something in the water, or a lack of oxygen at some elevations, or what but…

I’m getting asked “that” question again;

“Ronin, why can’t I just use that Ceramic Paint?”

At the risk of repeating myself over and over again…

In the beginning, there was Corten Steel.

He (or “She” – Hey, I’m “kinda” open-minded) who wielded that cosmic plasma cutter made clear that they were building a box so tough, that not even lesser gawds could harm it.

And then, them that was created in their image were walking up a road one day, saw one sitting out in the open, and said;

“Why looky there, Martha! It’s our next house! Go fetch the mules!”

And then, with a thunderclap that sounded exactly like the pop a torch makes when you put the igniter to it… ISBU Housing was born.

It didn’t take long for old Jed and Martha to figure out something was amiss. As the sun came up to warm the earth, that box started them to sweatin like a kid dancing for a happy meal.

(I know, because I was ONE of those kids, once.) 🙂

And then, like a bumblebee hitting the windshield it struck them.

Whilst they were each sitting in their galvanized watering troughs, trying to stay cool and not die from the heat… (Don’t you laugh! I have one in my front yard, as I type this!) they mumbled to each other;

“Lambikins… we gotta make us some changes around here.”

And the need for insulation was born.

We’re seeing ISBU homes depicted everywhere, nowadays. It’s not just the subject of the Sci-Fi Channel, it’s a topic that is raging on green cable networks globally.

We’re told that they are piled to the sky, blocking out the sun. Mountains of glorious non-corrosive metal shaped like Lego’s.

Big Steel Boxes that are cheap, strong, and “Tonka tough”.

And some of us WANT them with a passion that we usually only save for our wives and significant others. I’m talking “deadly sins” kinda Lust here…

And the biggest single limitation to using a steel box as a home, is that it resembles the steel box you already have in your kitchen. If you apply heat to either of them, they become ovens.

One of the problems to overcome when dealing with steel ISBU (Intermodal Steel Building Unit) shipping containers is insulation (or the lack theroef). You’re talking about a small-ish (308 square foot – approx) rectangular box that was designed to haul produced goods, and not designed to provide shelter to your tribe.

Opponents of ISBU construction will tell you that the inside dimensions aren’t very big, and if you furr/fir (take your pick) it out so that you can insulate them, you’ve just made a small box even smaller.

However… if you’re a smart person (and you really think it through) you figure out that the insulation actually goes on the OUTSIDE of the box. This has it’s drawbacks too, because now you can’t do that “Max Max – Armageddon Housing” thing that we’re all so fond of.

C’mon – the fact that you know all that exposed corrugated goodness would give your neighbor an aneurysm is a part of the joy, isn’t it?

No? Um… It must be just me, then… Sorry… 😉

Enter – Ceramic Insulation.

I get asked about these %&$%#@!! “miracle coatings” at least twenty times a week.

Seriously. I’ve actually started threatening people with “blog exile” if they continue to bring the topic up, that’s how often I get asked this… 😉

Ceramic insulation is a spray or paint-on coating system that manufacturers claim was “developed by NASA” to address “all three modes of heat transfer- Radiated, convected and conducted.”

And therein lies the biggest problem. Everything I ever learned as a trained architect, or witnessed in 30 plus years tells me that there is no free lunch, and that these claims are impossible to achieve.

Manufacturers like SPI Coatings (the manufacturer of SuperTherm, the most highly touted Ceramic Insulative Coating concoction) will tell you that their product “consists of a specially tuned compound of 4-different ceramics thermo-dynamically tuned to cover the IR, UV, & Visible Light Spectrum, the Thermal Spectrum from -40°-F to 450°-F; as well as 68% of the Sound Spectrum! SUPERTHERM ® is a Thermal Barrier NOT a Thermal Absorbent! It stops the thermal vibration continuance by its ultra low density.”

People at SPI will tell you that R-Values, the standard measure of insulation are just fairy tale numbers that don’t mean anything. Hmmm… that runs contrary to everything that I’ve even been taught, and essentially tosses an entire principal of building and construction in the trash can.

We’ve all seen the Youtube footage of Dave Cross (a builder who is now the head of SG Blocks.com and a guy that I consider an ” ISBU friend” of mine) handing Bob Vila a piece of Supertherm treated metal after he’d hit it with a blowtorch. Bob holds it with his bare fingers, amazed. Proves that Supertherm works. right?

Wrong. It proves that SPI came up with a good “flim-flam” demonstration to help sell their snake oil a gallon at a time. I think that it even fooled Dave for a while. I used to kid him about it when I talked to him… Just to rub it in…

Okay, so I’m like that… 🙂

Peter DeMaria, another architect (whom I respect a great deal, but disagree with about this topic), built what has become the most photographed home in the history of ISBU housing, his Redondo Beach, CA house. This 3200 square foot home uses Supertherm as insulation. He’s sure it works, or he wouldn’t have used it. However, that house is in Southern California. not Southern Montana. Los Angeles stays above 60 degrees most of the year, day or night. Move that house to someplace where there is “harsher weather” and I’m betting everything I have or will ever own, that you’re gonna need to re-insulate, pronto.

Surely, SPI has proven that this stuff works, to the guys that make it possible for the rest of us to use it, right?

Um… after they tested it, the EPA (the Environmental Protection Agency) said;

“The EPA does not recommend paints and coatings be used in place of traditional bulk insulation. We haven’t seen any independent studies which can verify their insulating qualities.”

Okay…

I’m a big fan of Alex Wilson.

Who’s that, you ask?

For more than 30 years, Alex Wilson has been the most trusted voice on energy efficiency and environmentally responsible design and construction. He founded BuildingGreen in 1985 and launched Environmental Building News (EBN) in 1992 as the first North American publication focused on green building. He built the reputation, resources, and staff that today makes BuildingGreen, the leading information company on green building, publishing not only EBN, but also the GreenSpec Directory, BuildingGreen.com, and LEEDuser, as well as providing consulting for a variety of companies for whom sustainable design is a core value.

HE has an opinion about “SuperTherm”, too;

“To say that there is a lot of hype about insulating paints and radiant barrier coatings is an understatement.

The Internet is rife with claims of paints that dramatically reduce heat transfer—usually based on some technological magic spun off from NASA. While these products may have some relevance in the extreme conditions of outer space, manufacturers of paints containing “ceramic beads” or “sodium borosilicate microspheres” are making claims that defy the laws of physics—and independent test results—when they claim they can save significant energy in buildings.”

Okay, so basically what he says is that to achieve their claims, SuperTherm would have to defy the laws of physics. And he makes it clear that independent test results don’t back up manufacturer claims, either. GULP!

As a trained architect with another degree in “test tubes and other junk that will kill you if you look at it twice without smiling…” I really make it a point to avoid using products that make outrageous claims that contradict science, cost outrageous amounts of money (I’m told that it’s up to $700 a gallon), are only hawked by people PAID to hawk them, products that supposedly negate everything that we were ever taught about construction (or physics) without being able to PROVE beyond a shadow of a doubt WHY in our right minds, we should actually do that….

Okay, okay… you get it. I’ve tried it. I’ve tested it (albeit in what some have deemed a rather “unscientific way”). I’ve used white paint too. Similar results, when it comes to insulating an ISBU. Neither one really works in the conditions that they were exposed to, but both do “similarly” well. Hmmmmmm…. again.

Look, I WANT this to work. Honest. If it did, it’d be a huge boon to ISBU builders.

Insulation is one of the HARDEST parts of getting ISBU homes built.

If I could find some miracle coating that could be applied in a business card thickness, that would take the place of inches or even a foot of insulation, don’t you think I’d be doing it? I’ve been working on these boxes since 1977. TONS of them.

It would revolutionize home building. You wouldn’t just use it on ISBU homes, you’d use it on all those old homes in America that can’t be insulated any other way, but by “repainting them.” You’d even apply it to cars and aircraft to take the place of insulation!

Why aren’t they doing that?

Um… because it doesn’t replace the need for insulation. That’s why.

Until someone can prove to me that ceramic coatings will work in every zip code in the US of A and take the place of insulation (with a set of tests recognized by the industry, tests that I can duplicate MYSELF), I won’t use the product, and if I’m working with you on YOUR home or building, I won’t let YOU, either.

I have too much love for my family, and even yours (which is saying something because I don’t even KNOW most of you, yet…) to put them at risk, based on snake oil spec sheets that are bandied about by “pie in the sky” internet websites.

And if you want to have a good laugh, take a look at some of the Ceramic Coating websites. Can you say; “Shoddy?”

Incidentally, myself and several other architects, engineers, and even builders have invited SPI and several other manufactures to rebut our claims on our websites, in an unedited fashion, so they can prove we’re wrong.

WE want them (at least I do) to be right. We just can’t figure out how it could be possible. and the scientists that we’re consulting can’t prove it, either.

My site, for example is one of the biggest “content based” blogs on ISBU construction on the Internet. I’ve gotten almost 300,000 views thru wordpress servers (where my blog “lives”) alone, this year, and about triple that in syndication.

And I’m talking about a “niche topic.” Let’s face it, how many people Google “DIY ISBU Homes”?

It’s been almost two years. No takers. And we’ve asked repeatedly. In fact, they no longer even respond to our email.

Now take all this a step further. If I can use pre-made steel boxes to frame my home, I can put them together to make large spaces, and even cut my labor costs, if I use a good design to start with.

And we won’t talk about repurposing, recycling or even resurrecting old unwanted materials to make it work cost effectively… will we? 😉

Wait, I just did. Oops.

While I’m preparing for a revolution, it has nothing to do with insulation. Except to insulate my family from it.

Ronin

PS. I get asked this question so often that I’m going to run this post for the last time, and then I’m going to make it a permanent “page.”

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14 Responses to “The Story of the Magic Insulation and the Steel Boxes”

  1. ted yrizarry September 2, 2010 at 9:41 am #

    But what about Ceramic paint…can’t I use it?
    Moahahaha…Sorry Alex, had to poke again! LOL! And I have been one of those askers myself as I am still a green horn learning my way. Does the prommise of an end-all/do-all, spray on insulation in a can possess the hope of the future? No more than my potential of holding a winning lottery ticket. It would be nice indeed, and may be a way to lul myself to sleep with an inmagined dream and a smile on my lips…But niether are gonna come to pass. You have gone out on a limb (big surprise) and poked the corporate hive of salesmen and called them to task to prove the reality of their “snake oil”. They won’t like that but I say…SO? Prove it or shut up! Like some current president claiming that everything will be grand and we will all live wealthy and safe. Prove it. Not doing so good so far.
    Ok, so with the application of C-coat debunked as a complete insulation miricle I wish to call you to task. Oh great swami of the steel structure…how do we do it? finish the big book.
    I know the first thing out of your mouth is likely to be DIY closed cell spray foam. I understand and I agree. By its nature it holds a better potential to fulfilling all weather conditions insulation requirements. Hot climits may need less. Believe me, I REALLY know how an uninsulated Connex can be oven like in the heat. No doubt there. But I think the cold is an even more difficult enemy to combat. And since it can’t really be “reflected” as well as heat radiating from the sun…it requires a little different tactics. Similar but not exactly a twin. So how do I stay warm in my little Corton cottage?
    As you race to apply fingers to keys in a response finish the big book I will as something a bit more specific and direct. Since applying the insulation inside cost space in an already small-ish envirornment, It becomes clear that you instruct towards the exterior insulation school of thought. Ok. And given that it will be spray foam being shot on the outside of the ISBU…How do you finish it? The outside of the container that is. Since part of the value of the ISBU is its weather tight structure, what can we do to retain this and still be comfy inside. I can only guess that spraying foam all over the outside will cure a great deal of the thermal issues but (finsih the big book) I can also see a potential problem. That DIY foam is not cheap or free. But sometimes we have to “pay to play” and I got that. Yet if this is the outside coating of my house…how do I ensure it will remain intact and serviciable? finish the big book
    I can only imagine that wind, water, cold, UV rays, and the occasional sparrow dropped coconut may cause damage to this coating. And after all the time and money spent to apply it how do we protect it? Notice that I don’t give a rat’s patootie about what the neighbors care of its asthetics. This is MY house! Until they desire to assit to give me money to build it they can…well, insert vile visual explitive here. Its mine, I’m building it, I am trying to pay for it, So its up to me to decide when it looks “cool”..if I choose to care.
    So get to typing Ronin. We (ok, me.) would like to know the better and perhaps cost effective ways to cover the foam to ensure it stays servicable with out costing as much as normal framing/sheathing methods.
    Thanks in advance and byt the way…I can’t wait for you to FInish the BIG BOOK! 😉

  2. Louise September 3, 2010 at 2:00 am #

    Hiya Ronin,
    I’ve seen good results with 50mm “coolroom panel”, which is styrofoam with a thin powdercoated metal skin (on one or both sides). Not sure what the fire rating is on this stuff, but in an Australian summer you can get away with not using air-conditioning for longer than plain cor-ten.
    You’re right, though – it does steal a lot of space from what is a small area to start with, but when you’re cutting out side walls for a decent-sized area it’s not as noticeable. You can still stick a queen-sized bed in the end of a single box (but it’s a tight fit… and not much room for bedside tables once it’s there)
    Apart from the fire rating (or possible lack thereof), the only other downside is that it looks a bit stark – not really a downside if you’re after an industrial look, though. The cost compares favourably (even a fair bit cheaper) than standard rockwool insulation and studs, and believe me it’s a lot easier to erect!

  3. guy September 3, 2010 at 9:53 am #

    I’ve read you rant and all i see is some one who’s education ended last century and has no idea of what has change since you went to school. you are like the prof who taught vacuum tube electronics when there students all walked around with transistor radios trying to convince them that vacuum tube electronics was the end if the line may be you need to go back to school and learn something from the 20th or 21 century

    • Renaissance Ronin September 3, 2010 at 4:48 pm #

      You know, I get comments like this all the time.

      Rather than actually say something that actually sounds “intelligent”, or heaven forbid you should even add some pertinent information to the discussion (like FACTS perhaps), you attack ME personally without saying anything “topical.”

      So, PROVE to ME that Ceramic Insulation takes the place of insulation in Home Construction.

      In fact, prove it WORKS, in a documented and industry approved testing procedure acceptable to Planning and Zoning (i.e. Building Codes) or shut the hell up!

      While you’re at it, maybe you shouldn’t frown upon “old school education”. At least we speak and write in proper English.

      And, thanks to jerks like you, I’m going to add the following paragraph to the bottom of all further posts:

      Commenting Policy: Ad hominem attacks against the site, its author, or other site members will result in your comments being deleted.

      To clarify: Ad hominem abuse (also called personal abuse) usually involves insulting or belittling one’s opponent in order to invalidate his or her argument, but can also involve pointing out factual but ostensible character flaws or actions which are irrelevant to the opponent’s argument. This tactic is logically fallacious because insults and even true negative facts about the opponent’s personal character have nothing to do with the logical merits of the opponent’s arguments or assertions.

      Examples:

      * “You can’t believe Ronin when he says that you can build a home yourself. I heard that his family is on welfare.”

      FYI: It’s actually been said. While the first part of the statement is true (in fact I say it all the time), the second is complete and total bullpucky, perpetrated by those with another agenda entirely.

      So, campers… You get one free strike. But redundant attacks will get you removed and then banned. Basically, be considerate and try not to be a jerk. That’s the author’s job. Isn’t there already enough unemployment? 😉

    • ted yrizarry September 4, 2010 at 12:47 am #

      Ronin! This is AWESOME! You found some magical way to get 3 year olds to write a comment! I always wondered what a childs view point would be if applied to the insights you share…now I know!
      So in an effort to dodge getting banned and since I can’t stand staring at the corner in “time out”…I will try and make this projectile a non-target specific one.
      In proven, grade school fashion you were attacked. That a grumble and a curse were likely given your persona was never in doubt but…Big Butt, as you stated, the assault was personal instead of professional. You recieved the “oh No…YOU ARE..NahNah!” response. Surprised you didn’t get your hair pulled or a rock thrown at you. Childish.
      So I join your ranks and add my voice in an effort to reiterate the crux of the difficulty here.
      PROVE IT!
      Yes, all you “New technology, battery opperated, take no responsablilty for my own actions and wait for some imaginary government institution to bail me out” folks saying this is the end all, fix all, super insulation that will never be bettered…Prove it or shut the Hades up!

      • Renaissance Ronin September 4, 2010 at 1:21 am #

        Hey Ted,

        I know you are, but what am I? 😉

        Is it practical to engage in immature personal attacks if you want to be taken seriously? Probably not.

        Is practical to engage in immature personal attacks to hide one’s inferiority, or the inferiority of one’s “product of choice”?”

        Um… probably YES. That way you don’t have to engage in the exchange of FACTS.

        Look, it’s not like I DON’T want it (ceramic insulative coatings) to work. The just can’t prove it, at a level that will allow it’s use (except in “special use” circumstances, like “one build” permit scenarios)…

        At the end of the day, there is no “easy-peasy” way (as my son would say) to insulate an ISBU, except by using… gasp… wait for it… INSULATION.

        Now I gotta get back to scrubbing “guy’s” crayon scrawlings off my monitor… 😉

    • lilchoke October 1, 2010 at 6:47 am #

      I recently graduated may 2010 making me one of the students walking around with “transistor radios”. i have found this site and Ronin’s info to be very helpful. I am working on my own design and company and greatly appreciate his info. In school discussions erupted about all this “new better technology” all that glitter is not gold. You do not get something from nothing. there is a cost, negative, drawback or something to all this new stuff. some is good but others…well like they say in upstate… “fugetdaboudit!”

      Reuse/up-cycling is awesome these days. rethinking blding sqft and size is awesome. in regards to the insulation… if it were true, then why is it not everywhere. if it was that revolutionary then it would be proven. tell u what… I got a challenge for u. take a regular ISBU, spray it with your magic spray, put it on a trailer and take around the country to the extreme condition areas and have the local college and univ do field tests of the insulating powers for hmm, a week. If it universally works, I’m all in.

      Just because a person for lack of better terms, has old fashion ideas (that are proven) doesn’t mean they are full of it. I think we all can use a little old fashion beliefs, doctrine or rule in our lives……

      (Editor’s note: Reformatted)

  4. Meghan Lee September 5, 2010 at 2:37 am #

    Enjoyed this post. I was skeptical about these “NASA” insulations. Now I realize they truly are “snake oil.” Thank you for looking out for everyone and giving your experienced opinion. I have been perusing your current e-book and anxiously await the new BIG book. I am so excited about the possibilities for ISBU-building.

    God Bless America!
    ~Meghan~

    P.S. I’m the person who is reading your blog in South Korea. I teach kindergarten outside of Seoul. It’s nice to not pay U.S. income taxes and the Korean tax is 3.3%!

    • Renaissance Ronin September 5, 2010 at 2:53 am #

      Thanks, Meghan!

      I envy you. Living in the “deep south” I miss real “Seoul food”… you know, stuff like Korean BBQ and Kim Bap! Still not much for Kim Chi, but it is, after all… an acquired taste. Boy, does that bring back memories…

      Enjoy yourself and keep reading!

      Ronin

      PS. At the rate things are going, you might want to stay there for a while… I’m betting that taxes (and just about everything else) are about to go up here… 😦

      • Meghan Lee September 5, 2010 at 4:33 am #

        Ahh, yes…the kimchi. I find I like it better when it is cooked. It’s a bit more like spicy sauerkraut when cooked.

        I plan to continue my overseas teaching gigs for couple more years. The money is much better than back home.

        At this point, I am trying to figure out what my savings goal needs to be. I really like your “Mother in Law” plan with the deck panel that closes up and the enclosed garage.

        Can you provide a ballpark estimate assuming I do the interior finishing work myself? I can lay tile, grout, install toilets, sinks, showers, countertops, cabinets, flooring, and other such things.

        Also, what is the square footage of that cabin?

        Thank you so much! Gansamnida!

        ~Meghan

        • ted yrizarry September 5, 2010 at 6:36 am #

          Meghan,
          If I may humbly interject…We are both similar in this. We both posess the skills required to perform the lion’s share of the labor. That in and of itself is a HUGE part of the savings. Another part, to me at least, is purchasing materials and supplies in a frugal manner (ok, cheap!). The trick is to resist the easy urge of wanting the new, shiny, and *gasp* popular in favor of less flashy and more economical alternatives.
          I’m a kinda average, single guy. As such I realize that my skills within a kitchen are less than stellar…which is fine. To that end I could never justify buying some big, fancy-schmancy stainless steel appliance. Unless, of course, it happened to possess a far less power consumption and longer reliability record. Scratch and dent, Craigslist, and garage sales can be a great way to save some more coin.
          Some items however should not really be considered to be purchased used. Stuff like wiring, sheetrock, Insulation…these things are sort of a one time use item. Could you find piles of sheetrock “drops” at a comercial job site? Sure. But the resulting jigsaw puzzle and labor intensive effort to reuse these would likely be not woth it.
          Tools are another area where being a DIYer is hard to resist. I have owned my own remodeling buiseness so most of the more expensive ones I already own. But for one that is not planning on making this a lifelong career (or did) the urge to buy some tool, sparkley and new, can be tempting. Borrowing is the best solution if you have a close knit groupe of handy friends. Just ensure that you take great care of borrowed items and return them promptly lest a friendship be tarnished. Renting is another option but not one I usually endorse…why? Well, depending on the tool, it may be better to seek out CL or some other source and buy one that is used. If it is something that will be never used again, ever, and is very expensive, then renting is a good option. If the possobility of future projects of shared projects with friends/neighbors may mean it will be needed, then find one used. Case in point.
          The expanding foam insulation system that is considered the best method to insulate our steel houses is not cheap. And depending upon how much one plans on sparying it may seem out of reason to buy it. Myself, I have friends that will likely be following eventually in my Corton compound collaboration…so the future use is there. Two options present themselves for this. All interested share in the initial expense like a “group buy” type thing and it makes its rounds as needed. Or, I could save for the purchase, use it for my application, and then “rent” it out to friends to help recoupe my investment. As long as all in the chain are responsable and use it with care it should be a good source of savings all around.
          There are also ways to think a little outside the box. Though this is a trend that is building steam, the use of recycled materials can, sometimes, be a savings. The biggist issue I have with this currently is that there are many places doing this as a source of income. They score a pile of used or unwanted lumber or whatever, spend some (maybe. maybe not) time and effort to clean or remove nails,glue, or whatever from the item. But by the time they are finished they have enough labor in it that the price over new is hardly noticable. One should always be cautious when looking into these type of things. Stuff like recycled hardwood flooring should be evaluated as to its condition. Will it require a great deal of re-milling in order to be able to be renailed as a floor? Lumber for and from a reclaimed deck. There is a tuff one. Some lumber is very resistant to decay and rot an UV, and if properly installed, maintained, and recycled may be a cost savings if the quantity is appropriate and the price is good. But buyer beware, if this is say a 25 year old deck that was made of pressure treated pine, built by some hack trying to make a fast buck, and never saw a day of cleaning or UV protection..you may be buying a lemon not even suitable for firewood.
          I wish you luck in your build. I hope you find great savings and can create a home that you will be proud of and can enjoy for a great many decades. Take pics, post the experience…enjoy!
          Sorry for butting in Ronin. 😉

          • Meghan Lee September 5, 2010 at 7:13 am #

            Hello Ted,

            Thank you for your reply. Craigslist is a great resource. Also, using other things in a new manner is smart. I believe the idea is called “upcycle” instead of recycle. Also, I think I will keep the walls steel. Why cover them up with sheet rock on the inside? That will save costs and space.

            I’m anxious to get some figures regarding the turn-key costs of small ISBU homes when the owner puts in a fair share of sweat equity.

  5. admin September 16, 2010 at 9:14 pm #

    great stuff bro, have you finished the “big book” ?

  6. Murk September 18, 2010 at 4:59 am #

    I just stumbled across your site and am enthralled. Kudos for being an outstanding being.
    Have you crossed paths with the materials classed as “aerogels?” They hold a number of records for material properties, and as I understand it its thermal conductivity is one of the lowest in existence. The solid alone would probably be cumbersome to install, but there are aerogel “blankets” or sheeting that some companies are producing which might fit the bill. One company that I’ve looked at is Aspen Aerogels. Here is a url to their “What is Aerogel?” page:
    http://www.aerogel.com/features/morphology.html
    Cool stuff. While schooled as a chemist, I lack the experience with any of the architectural formulas that you would be more familiar with… maybe it would be a worthwhile material for insulating your projects? Just a thought… I have only vague notions of how it compares physically and economically to other materials.

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