[Cob] foundation, concrete

[Amanda Peck]

Gernot Minke is pretty interesting--some years back I spent a long evening 
once going through pages and pages of a search, finding odd things like 
winners (he was a judge) of a natural building competition in Argentina or 
somewhere, for instance.

I truly don't know enough about earthquakes to tell you anything.

A couple of years ago I mixed some sort of vaguely light clay stuff--wood 
shavings and clay, packed a couple of samples with it.  Not tightly enough.  
There was a bit of shrinking.  But I expect that even if I had used sawdust 
it would be rough enough to take plaster quite nicely.  One of the 
samples--the one actually in a building isn't going anywhere--it's anchored 
with a couple of dozen screws every place they could be put into the frame.  
Next time I'm down at the barn I'll pick the other one up and shake it.

Early Americans used to actually use rain water to wash in and with.  But 
they set out spring water for drinking--it may indeed taste a little better. 
  But the water you're washing in and with does come in contact with your 
skin and clothes and dishes.  So, sort of, it's a better safe than sorry 
attitude on my part.  And right here it's kind of a long ways to the 
springs.  When I move up the hill it will be even farther.  Some of the 
metal roofs--galvanized steel or galvalume, a few of the baked on enamels 
are certified for potable water.  It's widely believed, although not known 
for sure, that all of the galvanized stuff is fine for a roof, maybe not for 
a cistern.  I want a low-slope roof, though, for one buildng, and the metal 
roofs work better on the steeper slopes.

One thing you can do on cob or other buildings where support might be ugly 
or a problem is to build the roof first, sitting on posts that will give you 
good overhang protection for your walls, and--easy for cob--build up to 
either the roof or a box-type plate that might be already installed.  A few 
brave souls--with small buildings and lots of friends have even built the 
roof too high and then lowered it onto the finished wall.  Gives you room to 
work out of the rain, places to put stuff.  It may be one of those things 
that should be run by an engineer before you try it, especially with a 
good-sized house.  I'm thinking that the building I'm planning that can be 
done this way can have the posts set close enough together so that the roof 
is supported enough that I could keep it a picnic shelter if I wanted.



....................

Predrag wrote (snipped):
Thanks again! I've tried to visit that URL, it seems the page doesn't exist
more, but I found other pages about professor Gernot Minke and his books.

I understand that nothing can help in a big earthquake, and I only would
like to prevent the house from smaller ones and from smaller earth slipping
(of course I should avoid choosing such places). In that case maybe grade
beam is not necessary?


Regarding wattle and daub I must admit that I haven't got a sense how earth
and straw will stick to wattle (and plaster as well) and what will happen
years after that? It seems to me cob will better accept plastering then
wattle and daub or I am wrong?

The idea about using roof to give potable water is also very interesting. I
was informed only about obtaining non potable water.