Cob: Smelly earthen floor

[Darel Henman]

Barbara, et al,
  I wrote a response earlier not realizing this was in the mail box.  So
let me add a little more.


Barbara Roemer wrote:
> 
> Hi cobbers,
> We have no toilet, sink,
> or shower yet,
Oh, I got the impression that it was an in-use bathroom.

> and when we bathe, we're exceedingly careful not to get
> water on the floor.
> 
Put a fan on the floor.  Open the window.  Turn on the fan, low should
do.  close the door to the rest of the house if its being warmed.


> The floor is not as smelly today as the humidity has dropped below
> 95%, and I did receive helpful info about using grapefruit seed oil.

Linseed oil has also been mentioned don't forget it as a possible
covering.

> 
> I find it interesting that Japanese builders intentionally use straw
> and let it ferment in the floors. 

I must not have been clear here.  They don't put it in floors.   

> Wonder why?  (regarding fermenting the straw)
They use it for daubbing (cob) onto wattle walls.  Why they do this is
because they feel that the lignin and pentose come out of the staw
fibres and adds morse stickiness to the mix and results in a harder
resulting wall.   Not also that they don't do this to all of the
straw.   They also feel that keeping the soil wet for a long time (up to
a year of more for temples), three months average, but at minimum two
weeks, is to let the iron in the soil oxydize and to let the organics in
the soil float to the top and not used.   For the long soaking period
they add the straw in not all at once in several additions.   The reason
for this is said to be that the most fermented straws, still have small
fibres that grab the smaller clay particles and bind them together, and
the lesser fermented and larger straw fibres then bind these together
and so on until the newest straw added a day or two before application
is then to hold all of the largest clumps together.

The Japanese mud masoners also say its important for the straw and soil
to get used to each other they begin to meld together and the soil
changes color after soaking for three weeks.  The optimal lenght of time
for soaking the soil prior to use depends on the temperatures, but on
rule of thumb is at least until the soil changes color and black mold
forms on it (this is the oxidized iron I think or rust from it).

For floors in Japan, from what I read, I hope to see some the end of
this month, the (tataki) or tampered floors consisted of 
	1. a granite soil, 
	2. lime, 
	3. water, ( with optional salt or Magnesium-chloride left over from
salt making)
  
 These ingrediengs where mixed in a semi-dry mix and then tamped/rammed
down to about 50-67% of the before packed level.  This technique was
used for entry and kitchen floors and sewer lines. and runs around the
house and was in use until about 70 or 80 years ago in the country side. 

 They used this for some fence walls as well.  Sometimes they would put
a vegetable oil in it to aid in water protection, but one has to not
over due the oil part.

 I was just using their wall daub mixtures as an example of the smell of
fermenting rice straws.

>  Whatever ferments
The straw ferments.  Caused by little micro-organizions inherently on
the stalks or by the mico-organizms in the soil itself.  It very
natural.  I've made vine vinegar just by squeezing grapes and letting
the mash sit in a glass jar (allow it air) for a couple of months.   The
needed yeast and vinegar microbes are on the grapes themselves.  If you
try this, I recommend, that you use organic grapes the yeasts are
healthier......

> I prefer to be potable, but this isn't in the same realm.
Wine is potalbe, isn't it?

> As for common
> sense, I'm afraid I have plenty, and hope to spend more of my life
> with my feet off the ground.
> 
Cheers

> Barbara
> Nevada City, California

Darel