[Cob] cob walls and climate

[Robert Alcock]

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> Message: 2
> Date: Sat, 5 Nov 2011 10:23:06 -0700
> From: Janet Standeford <janet.standeford at gmail.com>
> To: coblist at deatech.com
> Subject: Re: [Cob] Insulative values: Frank, Mike, Janet, Sky, Chris,
> 	others?
> Message-ID:
> 	<CAMwY=YMenDXenMVvVnHwPF6TyhqiHLXwneMFC=3oN+NBsiK0VQ at mail.gmail.com>
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>
> I am so sorry Sky but I think the Larson Truss technique would be good for
> straw bale. Not Cob.
>
> Many homes in Europe and other places are cob and they don't seem to be
> using so much wood. They are comfortable as well.
>
> Don't forget thermal mass is key here and that is what my house will have.
>
> Trying to turn cob into a hybrid isn't what this site is about as far as I
> am aware.
>
> It is to encourage the building of cob homes with permits.  This entails
> satisfying code, not changing everything into something that doesn't
> resemble cob anymore.
>
> I applaud Tys and anyone else who has the fortitude and guts to see this
> goal through.
>
> Don't worry about me being cold. I have kept warm on very little heat with
> far less insulation or thermal mass here.
>
> It's good to have walls that breathe Sky. It is not good to be in an air
> tight coffin.
>
> Janet
>
>
> ------------------------------
>   
Hi all,

I think one thing that needs to be taken into account is the fact that 
south-west Britain, where the cob technique originated, has an Atlantic 
climate. Winters are wet and windy, but temperatures rarely go below 
freezing for long. If you live in this kind of climate (like we do, in 
northern Spain), you can get away with an uninsulated cob wall - 
depending on the wall's thickness and its insulation value, of course. 
But in a continental climate where you have months on end of very low 
temperatures, a cob wall without some kind of external insulation will 
lead to a very cold interior. I think this mailing list is supposed to 
be about cob in all its applications, hybrid or otherwise.

Another thing to think about with respect to thermal mass is where your 
mass is located in the building. If you have a big lump of thermal mass 
around your stove, which is in the middle of your house, that mass is 
going to retain heat a lot more effectively than it would if it were 
directly connected to an exterior wall.

Robert
www.abrazohouse.org