[Cob] termite protection of earth floors

[Barbara Roemer]

Here's a long reply to Simon's post.


Of earthen floor protection from termites, Simon wrote:

>
> One of my big nightmare scenarios is termites boring through the floor
> and eating the furniture.
>

My nightmares, exactly. I'd fall asleep trying not to worry about it, and
find myself in vivid dreams with the bathroom (earthen) floor plates
disintegrating, and the termites having travelled up the posts, across the
beams, and into the second story, leaving the framing Swiss cheese and the
house near collapse.  It's been more than a decade now, so I no longer
worry, but doesn't mean it couldn't happen or BE happening!

>
> For our room we placed at great expense a layer of commercially made
> pyrethrum impregnated plastic sheeting directly on a smoothed subsoil
> clay base and then four layers of soil and sand mix.


I'd like a website or product description for the pyrethrum sheeting.
 Sounds like a good idea.  I prefer to keep gravel on either side of the
plastic sheeting, since it doesn't take much soil for termite travels, but
then there's the possibility of puncturing the sheet.  My experience is too
limited to know....

SNIP

>  We also had the problem that the Linseed oil didn't soak in and
> remained wet on the surface. To counteract this we put newspaper down
> over the whole floor and left it there for a few weeks while still using
> the room. The newspaper worked a treat at soaking up the excess oil.
>

What a good idea.  Did the print come off on the floor, or did you use
unprinted newsprint paper?  I know the ink cleans up easily, and in most
places, economics now dictates soy inks. The biggest disadvantage with oil
sitting on the floor, even a thin layer, is that it hardens just to sticky
and is very difficult to clean off (Simon, you probably already found this,
and others have heard the litany, I"m sure).  Now, for annual oiling, I
just put on a reasonable amount of oil, judged by pouring it into a pool
and swabbing it out with a soft cloth, wait for that to dry and do it
again.  It does mean I"m waiting a couple of days either in between coats,
or at the end for two coats to dry completely.  High traffic areas
sometimes require three coats, or look best, like rich leather. Our floor
dries out during the 5 months of arid summer weather, so sometimes I put
another layer on then.  Usually, I just do it in the fall and set the oil
either in the sun or near the woodstove (yep, keeping a close eye on it as
it's flammable) to thin so it penetrates.

I used to follow a regimen of several coats, each diluted with successively
more thinner of some kind, and some years tried the opposite, with the
thinned layers on first, but results seem no different with thinned oil
than with just heated oil.  The Steens have found similar results, and they
may soon have revised their earthen floors book to reflect their current
practice (which would be quite a bit different from what they did when they
first started out!).  Check their website:

http://www.caneloproject.com/about-us/


> Next time i will thin the oil down or might try to get the Bioshield
> Hard Oil. Do you know what type of oil it is, is it based on Tung Oil?
>

Here's the list from BioShield's website:

Ingredients: Linseed Oil, Tung Oil, Colophonium Resin, Castor Stand Oil,
Isoaliphatics, Lead-free dryers (Zircon, Cobalt Octoat), and Oximes
(Anti-skinning Agent).

I don't like the heavy metal driers, but am not sure what else to use (and
linseed oils have them, too, unless you follow the Steens' advice to sun
dry).

>
> The reason i am asking about the Boric Acid is a friend of ours is just
> starting to build a straw bale house and will be living in a shed while
> they are building. They saw our earth floor and loved it, unfortunately
> they will not be able to use it in their house due to building
> regulations but want to use it in the shed without paying the exorbitant
> price for the plastic sheeting we have used. I am also interested in the
> extra layer of protection that putting Boric acid in the floor mix
> should give.
>
> Simon
>

There may be a reference to the concentration of boric acid we used in
friends' straw clay mix.  See *EcoNest, Creating Sustainable Sanctuaries of
Clay, Straw, and Timber*, and look for the Hovemann/Weaver House.

Good luck with your project, Simon ~ it seems well-thought out.

Barbara Roemer
Sierra Nevada Foothills, Northern California



-- 

We are silence,
We are golden,
We are billion-year-old carbon,
And we got to get ourselves back to the garden.

                                                   -Joni Mitchell