Rethink Your Life!
Finance, health, lifestyle, environment, philosophy
The Work of Art and The Art of Work
Kiko Denzer on Art

[Cob] building with shipping containers, straw bales, and cob

Marilyn Pratt marilyn.pratt at
Sun Jun 29 20:45:19 CDT 2008

John - More info on the cob wall the deadman with the (almost) rusted-away nails, plus comments on combining cob and other materials in this reply from Kirk Mobert, aka Donkey, a terrific instructor at the course I just took at Cob Cottage Company in Coquille, OR:

"The building is in Oakland down there by you. It was an exterior wall, 
covered by a roof. Though it was some of the poorest cob I've ever seen 
(bad mixes, high silt, crumbly, not enough straw, other junk mixed in), 
it did manage to hold up a FAR too heavy roof structure. It didn't 
appear to have any water damage, the roof seemed to have done its job 
well enough. The deadmen were covered well in cob, no obvious voids or 
cracks to let in water. The wooden bits were in fine shape, it's just 
that the nails were practically gone.

I suppose one could use cob and containers (you do mean steel shipping 
containers?) together, though I would hesitate to do so. It's my feeling 
that any connection between the two materials would tend to separate. 
Also the steel would probably become a condensation point for moisture. 
Condensate would then run between the cob and steel and eventually wreck 
the cob, possibly rusting away the steel as well..
There may be ways to solve it. Some kind of spacer between the cob and 
steel to allow vapors and/or condensates to flow away or drain down.

As always the best policy with water is to give it easy escape routes. 
Keeping water out is a cute theory, though it rarely lines up with reality.
Shipping containers can be pretty good at trapping moisture, both in 
keeping it out AND keeping it in. One of the main problems with living 
in the things is condensation. The interiors are almost always damp and 
uncomfortable, unless you go through some pretty heavy maneuvers to 
allow vapors out, essentially poking a bunch of holes or something like 
that, then trying to keep the holes from bringing in yet more moisture, 
etc. Also, shipping containers tend to act like a Faraday Cage, which 
can play havoc with the body's electrics..

As usual, it depends.. Thirteen and all that. :)
With a bit of cleverness and careful thought, it could work."

thanks, all -

----- Original Message ----
From: john fordice <otherfish at>
To: Marilyn Pratt <marilyn.pratt at>
Cc: Robert Alcock <ralcock at>; coblist at
Sent: Thursday, June 26, 2008 6:59:13 PM
Subject: Re: [Cob] building with shipping containers, straw bales, and cob

What do you know of the wall conditions?
Was it an exterior wall of a building?  Did it have a roof?  Was it a freestanding outside wall?  Anything you can add?
other fish

On Jun 26, 2008, at 3:33 PM, Marilyn Pratt wrote:

I'll add this thought to the mix...  not from experience, but something from a class I just took from Cob Cottage Company.

One of the instructors has had to deconstruct a wall that had a wooden deadman in it.  The deadman was originally decorated with lots of bent nails, to hold it in place and help give it tooth so it would not move inside the cob wall.

When after a year or so he had to go back into that section of the wall, all the nails had rusted completely away except the parts embedded in the wood.  No trace of nails outside the wood.

Remember cob needs to breathe.  It passes moisture while doing so.  I'm guessing trying to combine natural materials with the containers might not work well in the long run.

But I'm just a beginner...

----- Original Message ----
From: john fordice <otherfish at>
To: Robert Alcock <ralcock at>
Cc: coblist at
Sent: Thursday, June 26, 2008 2:30:05 PM
Subject: Re: [Cob] building with shipping containers, straw bales, and cob

I'd be concerned with moisture condensation on the interior of the  
steel container, at least while the cob is drying.
other fish

On Jun 26, 2008, at 12:54 PM, Robert Alcock wrote:

> Not to want to buck the trend, here, but I don't think this post is so
> off-topic... the poster is, after all, asking how to incorporate cob
> into a particular form of construction (with containers).
> I would say that cob can likely be used to remodel the interior of a
> building with almost any material, including steel containers. You  
> would
> need to paint the steel with an adhesion coat, something that will  
> stick
> really well to steel and leave a rough surface. The cob would give a
> comfortable, organic interior with high thermal mass, which would be
> useful because I imagine containers would tend to be pretty  
> uncomfortable.
> Thermal expansion/contraction in the steel might present problems. My
> only experience with cob and steel has been setting a steel woodstove
> into a cob fireplace, and I have found that the cob cracks because of
> thermal expansion of the stove. So far the cracks aren't fatal, and we
> have achieved the intended result (linking the stove to the thermal  
> mass
> of the house core).
> Robert
>> I agree with Tim...this is the weirdest off-topic post yet to show on
>> the cob list.  Come on, this is the COB-LIST, not the "container-
>> list" or "steel-list" or "strawbale-as-insulation-list"
>> You should only post to this list if you want to discuss COB  
>> building!
>> On Jun 25, 2008, at 11:56 PM, Tim Nam wrote:
>>> Do you have access to free containers or something? I mean, why not
>>> just stick with the strawbale and cob?  Just asking.
>>> I would use the containers for a basement, if at all.
>>>  Tim Kijoo Nam
>>> Corvallis, OR
>>> tkn317071 at
>>> "We are discussing no small matter, but how we ought to live." -
>>> Socrates
>>> ----- Original Message ----
>>> From: Selvoy Fillerup <selvoy at>
>>> To: coblist at
>>> Sent: Wednesday, June 25, 2008 6:12:21 PM
>>> Subject: [Cob] building with shipping containers, straw bales,  
>>> and cob
>>> All:
>>> I?d like to discuss the possibility of incorporating recycled
>>> shipping containers with natural materials (such as straw bales and
>>> cob) to create a natural/industrial blended home. I prefer the
>>> organic look and feel of natural materials and would like to use
>>> containers as a skeletal framework on which to build. Does anyone
>>> have experience with both methods of construction?
> _______________________________________________
> Coblist mailing list
> Coblist at

Coblist mailing list
Coblist at