[Cob] Washington DC cob: The experimental wood chip and paper clay wood shed

[Henry Raduazo]

	I am sorry i think I missed something. Who's lives are in danger?  
This is a wood shed 100 yards from any other structure. I am and  
engineer and I have a great deal of respect for good engineering.  
Some times there is no way to advance a science with out making  
experiments. Some times established standards make no sense. Suppose  
I can make cob with 300 psi compressive strength. Great but does it  
make sense to require that all buildings be made with this cob?
	You know we have already had this debate with concrete. By reducing  
the amount of water and using resin fillers you can make super  
concrete with twice the strength of ordinary concrete. So why don't  
we use it? The answer is that it is too expensive. Ordinary concrete  
is good enough for 10 to 12 story buildings and for 30 story  
buildings steel construction is cheaper and gives the architect more  
flexibility. You can of course write it into the code which means  
everyone will have to use it because it is required by the code. I  
think that is what people have done with cob. It does not make  
engineering sense. Good enough is good enough.
`	I am trying to prove or disprove weather this will work by building  
with it. In a year or two I will know weather this is a success. I  
have done small samples and destroyed them. I have built an ambitious  
structure that I think will test the limits of this material. I have  
supported a 30 foot by 7 foot roof on top of three 8 inch thick L- 
shaped and T-shaped wall segments. I often get heavy winds off the  
Potomac river. I expect blowing winds will get the wall segments wet  
occasionally. I expect that the walls will be exposed to freezing and  
thawing this winter.
	If it fails I will learn something. If I never try anything new, I  
will learn nothing. I encourage everyone to be conservative when  
building their homes. When you build a home you provide a good  
foundation, but when you build a stone wall or a cob wall around your  
garden a shallow foundation is good enough. If it falls down you  
rebuild it.
	Cob is thousands of years old. The people who developed it are dead  
and their knowledge died with them. It is up to us to create our own  
body of knowledge. We will do this by experimenting with the  
materials that we have and reporting on our experiments, our  
successes and our failures.
	Cob will never have the certainty and predictability of concrete and  
steel. Every part of the earth differs from every other part of the  
earth. If you want to build with cob you must first be a scientist.  
Take the dirt from under your feet and experiment with it. How strong  
is it? Make blocks and test them for tension, compression, abrasion.  
Is it good enough?  If it is then you become an engineer. How can I  
quickly and efficiently make 20 tons of this stuff to build my house?  
If the earth under you feet is not strong enough to support a wall  
then you look for something else. If you do not have straw you look  
for something else. If you do not have cow dung you look for  
something else.

Good enough,

Ed
On Sep 26, 2010, at 3:42 AM, L.M. knecht wrote:

>
> (Refer to thread below)This is irresponsible. It can never be up to  
> 'good enough' to put lives in the balance.'Good enough' to whose  
> standards? An off the cuff experiment's?Experimentation is no  
> stranger to me, but I would never advise or inform anyone to the  
> use of an unproven method. Triple, and quadruple, testing and a lot  
> of patience ( time ) is what merits credence.Whether you agree with  
> building code, or authority in general, it makes it harder to gain  
> momentum in the realm of sanctifying natural building methods when  
> un-verified sources reporting on experiments are passed along  
> threads like this, without the proper facilities to perform and  
> organize such a test.Just because you stand on your roof now does  
> not mean that it will stand up against time and most importantly  
> the elements. You said you had been an engineer- not all are  
> trained for the same kind of engineering. Were you structural  
> engineer? Engineers are trained in specialty areas, and not all of  
> them are able to go from one to the next.If you want to beat the  
> record of contemporary builders then you will have to stand up  
> without structural failure for 10-15 years to know if your  
> experimental methods compete. A few days/weeks/months are not going  
> to be able to attest to that.Personally, I believe that Cob  
> construction, and other earthen building techniques, are the most  
> sustainable ways to build. We need to continue strengthening that  
> argument.Only use the necessary technologies. And we don't need to  
> question the validity of a traditional cob mix that has already  
> stood the test of time, unless we are bringing something in new  
> that is at least equivalent in strength.This takes a studied  
> approach to design and construction, and must not be  
> underestimated.-Liam> From: raduazo at cox.net> Date: Sat, 25 Sep 2010  
> 21:51:39 -0400> To: howard at earthandstraw.com> CC:  
> coblist at deatech.com> Subject: Re: [Cob] Washington DC cob: The  
> experimental wood chip and paper	clay wood shed> > I have been  
> walking on the roof it seems plenty strong enough. If it > blows  
> over or falls down this winter I will learn something. That is >  
> why I experiment. I am also using an available material (paper)  
> which > appears to be superior to horse shit. In several plaster  
> situations > where both manure and paper clay were exposed to the  
> weather The > paper/clay/sand mix lasted longer. Most paper  
> components are > biodegradable. My recycling paper into a composite  
> roof material will > not cause more of it to be created.> I use  
> shredded wood because I can get truck loads delivered to my > door  
> free of charge. When someone delivers a truck load of hemp to my >  
> door free of charge I will use that. I don't mind it if wood cob is  
> > weaker than straw cob. I am mostly interested in the science of  
> "good > enough".> > Ed> On Sep 25, 2010, at 7:41 PM, Howard Switzer  
> wrote:> > > I'm not sure I understand what makes you think your cob  
> building > > with wood chips in lieu of straw was a success. Did  
> you do a > > lateral forces structural test of it? Getting a mud  
> wall to stand > > is not so difficult, I was at Pine Ridge recently  
> and saw some big > > thick walls someone had done that had almost  
> no clay in them, > > mostly they were silt. A lateral force, of  
> course, could bring > > that mess down hopefully with no deaths or  
> injuries.> >> > The point of straw, long grasses, in the cob is to  
> provide lateral > > reinforcing(shear strength), length matters,  
> wood chips not being > > very long are not likely to do that, more  
> likely making a weaker > > wall by displacing cob. Test it against  
> good cob and let us know > > how it does. On the other hand there  
> are probably better materials > > for lateral reinforcing such as  
> hemp and probably Kudzu as well, > > both are toothy compared to  
> the slick sides of straw.> >> > I am a big fan of experimentation  
> so I am not talking from any lack > > of experience, but I do  
> caution folks that it is important to learn > > the nature of and  
> especially function of materials for building so > > suitable  
> alternatives can be used. Building with what is a > > available is  
> appropriate but a material's use should be appropriate > > too.  
> Just because you can do something doesn't make it the right > >  
> thing to do, necessarily.> >> > You were reeling at the un- 
> naturalness of local manure and > > straw ...but not the un- 
> naturalness of chlorine bleached paper not > > to mention toners  
> and ink?> > Not sure I understand.> >> > best wishes,> >> > howard>  
> >> >> >  		 	   		
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