Cob: RE: Insulation for cob

[Michael Saunby]

On 17 July 1999 22:16, alexander neumann [SMTP:alex at privat.kkf.net] wrote:
> ...
> Here in germany I would not build uninsulated exterior cob walls, not to
> mention that itd be illegal. Id rather go for strawbales, but thats also
> somewhat illegal still.
>
>

As Don has asked for facts on cob and various others have voiced opinions 
on matters ranging from the use of newspapers as insulation to the many 
uses of sawdust as insulator and composting aid, I thought I'd jump in and 
offer a few perspectives.  These don't answer any of the questions but 
might help those who cling tightly to convention to see where the other 
side are coming from, both historically and with an eye to the future.


On laws, codes, and regulation.
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Alex suggests that cob would be illegal in Germany, I've no reason to doubt 
him.  The many USians on this list regularly mention "codes", in England we 
have "Building regulations." These are by definition local affairs, in a 
way they are a statement of what was regarded as good in the immediate past 
in a particular locality and a recommendation of how to build today.  Since 
many on this list are still considering tomorrow, the regulations, laws, 
and codes applied to building are relevant but are not (in most states) 
incapable of change if change is desirable.  Cultures, like laws, also tend 
to be local and also do not, for various reasons, embody solutions to every 
human problem, it may be that the finest way to make a chair for example is 
not the way your grandparents made them, or the way my grandparents made 
them, but the way of some remote Chinese village.  The Internet is allowing 
us to share knowledge across cultures, but to make sensible use of this we 
need to recognise that cultures and laws vary so not every bit of well 
designed and well intentioned law is the realisation of some absolute 
physical fact (e.g. cob is NOT a suitable building material because it 
doesn't have an R value of ??) or some cultural fact (e.g. cob has never 
been used here before so it can't be any good).

On the suitability of cob.
-----------------------------------
The constant concern about the insulative properties of cob should perhaps 
not be taken by cob enthusiasts as a criticism, but an indication that the 
battle for cob is almost won!  I say this because throughout the long 
history of permanent structures as home insulation is a very new arrival. 
 The primary purpose of a permanent structure as a home is for security 
from other people and wild animals and protection against adverse weather, 
they also make a good place for social gatherings, etc.  The fact that no 
one seems to be attacking the structural properties of cob must be a good 
sign.

On why insulation is important.
--------------------------------------------
In the last 40 years or so a couple of important things have happened to 
make insulation important in colder climates.  The first has to do with 
global power (the human kind), for a long time the oil producing countries 
frightened many governments, then the oil and gas multinationals managed to 
gain the power, the governments were still frightened.  In the last 20 
years environmental concerns have entered the mix and the pressure 
continues to be on individuals to minimise their use of fuels through high 
taxation, etc.  Don't get me wrong I don't want to see foreign governments 
or multinationals holding everyone to ransom, and I don't want to see (or 
breath) pollution and waste, but I think it's important to recognise the 
history of the importance of insulation.  Other parts of the world will 
vary but in the UK the majority of the housing stock is actually rather 
older than 40 years so most homes are poorly insulated, my own house is 
300+ years and I've spent most of my life in houses with solid walls 
(usually brick with no cavity).

On your environment.
-------------------------------
One of the things that attracts many people to the idea of building in cob 
is the idea of low environmental impact, the use of local materials with 
low energy input and when it's no longer needed no one need ever know it 
was there.  An important part of minimising impact is how you live, maybe a 
lifestyle change would make cob more attractive, perhaps when you've got a 
cob home you'll spend more time there, travel less, wear more (or less) 
clothes depending on the weather. One rather narrow and to my mind 
uninteresting aspect of personal environment is in the construction of an 
environmental cocoon where your temperature (and humidity?) is kept 
constant for 12 months of the year (24 hours a day?) at the lowest possible 
energy use.  Sure as an engineer I can see it has a few interesting 
technical features, but only a few.  There's much more fun than that to be 
had in creating a stimulating and pleasant space in which to live, work, 
etc.

On everyone else's environment.
----------------------------------------------
The world does seem to be changing.  Rich countries are expecting poor 
countries to maintain important forests, etc.  Poor countries are expecting 
rich countries to burn less oil and gas, pay fairer prices for raw 
materials, etc.  Most of the world's population are either living in poor 
countries or they're poor people living in rich countries (which might be 
worse).  Whether you view your own impact in terms of what you do now to 
help, or what you leave behind, even if it's just a house that will provide 
shelter to other families for a couple of centuries or more, it's important 
to consider how what you do will impact on others.

Michael Saunby