good news

[Shannon C. Dealy]

On Fri, 6 Dec 1996 goshawk at gnat.net wrote:

[SNIP]
> 2. I will bring out a dump truck of gravel and fill in the bottom of 
> the footings with the gravel, then using cement and granite rocks and 
> cement begin making a stem wall. From what I understand it should be 
> three inches greater of each side of the cob wall. I live in a hot 
> summer / mild winter (still some below freezing weather). I thought 
> of  18 inch thick wall. Sound good? too thick?

I don't know of any reason to make the foundation significanly wider than
the wall, Cob Cottage makes their walls about the same thickness as the
foundation.  I would think that it would actually be a bad idea to make
the foundation stick out beyond the wall on the outside, since it might
tend to accumulate water on the lip of the foundation wall and keep it in
contact with the cob.

I don't think it is possible to make a wall to thick, some of the English
buildings have walls around four feet thick (though you might make
Hercules look like a wimp when you are done).  Sixteen to eighteen inches
is I think pretty typical for exterior walls on new cob construction.

> 3. how high should I make the rock stem walls? Is one foot above 
> grade too high (or can you be too high).

One foot above grade is the approximate height used in this area, though
you could probably get away with less if you are in a drier climate and
your building site is well above the water table and any runoff that
occurs when it rains.

> 4. Window and doors. Can you still use headers like in regualar 
> construction?  

Yes, though they will probably need to be a little heavier duty.

> 5. The floor. I am thinking of a wood floor off the ground with a 
> crawl space under house to run electic wires and plumbing. If I was 
> doing an adobe floor would these thing be imbedded in the floor?

I suppose you could put them in the floor, though I think most people tend
to put them in the walls.  Personally I would run wires through whatever
you need to, but I would try to keep plumbing out of cob/adobe walls and
floors as much as possible.  A leak in a cob wall or floor might go
undetected for quite some time and cause some damage, In addition it
would take a fair bit of work to fix the problem.

> 6 let me know anything I should pay close attention to while drawing 
> up plans. 

Nothing comes to mind at the moment.


Shannon Dealy
dealy at deatech.com