Cob mini bale alternative

[bufflocp at telusplanet.net]

Will, hello to you too.

Hot lime has been prepared in such a way that it has a chemical affinity
for water. Dry salt is like this too. If left in an open pile in a humid
room, it will absorb water vapor from the air  (it hydrates, which is just
the opposite of "dehydrates"). In the case of some chemicals, in this case
lime, when the water is taken on, energy is released in the form of heat
due to a stronger bond being formed with the hydrogen part of the water
molcule. (You might remember the term "exothermic reaction" from your
high-school chemistry.)

Hydrated lime, according to our local experts, is the non-hot variety and
is more commonly used these days. It is chemically more neutral than hot lime.

In any case, either form of lime is just fine for mixing up a batch of
morter, stucco or plaster,  with the hot variety being quite handy if there
is a need to keep your mixture warm for a longer period of time, such as
during a cool-weather job. Another excellent use for hot lime is down the
outhouse hole. It is a rather powerful base (opposite of acid) and will
speed organic chemical decomposition as well as control the fly problem. It
will, however, also burn your skin slowly or your eyes rapidly (thus
controlling the sight problem) if you are careless.

Some few years ago (not as few as I'd like), I ran into some difficulty
when building my stackwall (cordwood) home. We had been using the
lime-sawdust mixture as insulation for quite awhile, and had depleted the
local supply of hydrated lime. The store-guy convinced me that his hot lime
would be great, killing all those nasty insects and even helping to insure
that the interior wall space would be extra-dry as construction proceeded.
We used a bag of it to mix with our dry sawdust and used the mixture later
that day to insulate the next 10 foot spiral section of our wall.

Fortunately, the smell of smoke awakened me that night. Also fortunately, I
ignored my inclination to dismiss the odor as having been blown in from one
of the distant forest fires that were burning that summer. I, dressed in my
briefs, located the hot spot on the wall and worked from 3:00 a.m. to dawn
sledging down the better part of a week's labor as I tracked down the
smoldering fire which had started as a result of spontaneous combustion.
The hot lime (AKA quick lime) had pulled enough moisture  out of the "dry"
sawdust to partially hydrate and the resultant heat had nowhere to go.
Such, however, are the ways we learn. (Me, anyway.) For instance, I learned
to sleep with my pants on.

Now, earth walls won't burn away to nothing, but I'm not sure you want to
be the one to prove or disprove that a cob wall cannot be harmed by
excessive heat. On the other hand, maybe you could be the first person on
the block with a raku home.   :-)    Ron



At 09:42 AM 3/11/98 -0800, you wrote:
>
>Hi Ron,
>
>Could you explain the "Not the hot variety" comment? Is it the lime that
>heats up? Why does this happen?
>
>Regards,
>Will
>
>>-----Original Message-----
>>From:	bufflocp [SMTP:bufflocp at telusplanet.net]
>>Sent:	Monday, March 09, 1998 10:25 AM
>>To:	coblist; WFIRSTBR
>>Subject:	Re: Cob mini bale alternative
>>
>>
>>Hello!
>>           Your honeycomb idea is intriguing. You might also consider
>>sawdust or shavings as an insulator if either is readily available to you.
>>In any case, as insurance against the possibility of insect infestation,
>>give some serious thought to including lime as one of the constituents of
>>any dry-mixed insulation (stack-wallers do this). Not the hot variety,
>>though. It would heat up inside the wall and could cause problems. Ron
Hanson
>>
>
>