[Greenbuilding] Smart house designs

[Chris Green]

Ian Remmler wrote:
> I've thought about earth sheltering, but around here we have
> about six inches of soil, then solid limestone, so it probably
> wouldn't be too feasible.  So, no basement either.
>   
You have limestone on your property? Lucky you! (...maybe...)

In New France, mostly in today's Quebec, the farmers used to uncover the 
limestone deposits on their holdings and use that for building. In their 
case, the limestone held a lot of water and so was soft enough to cut 
with a handsaw. Once they'd cut and shaped their blocks, they'd leave 
them until the moisture evapourated from the rock. In doing so, the 
blocks would 'harden up' and be useful for building.

This was a common winter activity for the farmers, and in the spring 
they would have a supply of blocks they could take to the nearby towns 
and cities to sell to contractors there.

The broken bits could be burnt and turned into  lime. The burnt lime is 
then 'slaked' with water to make lime putty, which can be used for 
plastering or as a mortar. The old stone buildings in Quebec have walls 
made from broken limestone (and other rocks) held together with a lime 
mortar. It is possible to build a rammed earth-type wall, and these are 
called rammed limestone.
Rammed limestone construction was common in parts of England, and is 
being rediscovered today around the world.
To see what this can look like, see the photos of the Cheslow/ George 
residence shown on the bottom of this page:
http://www.solumbuilders.ca/
You can search google for more about rammed limestone.

Rammed earth and rammed limestone construction is quite labour 
intensive, but the material cost can be almost nothing if you're in the 
right location.

Another type of rammed earth construction is the Alker method being 
developed in Turkey. Alker construction is rammed earth with 10% gypsum 
and about 2% lime added in place of portland cement. This type of 
construction seems to be able to use soil with a lower than-usual clay 
content. The problem is then in getting a sufficient supply of gypsum, 
which can be a challenge in some areas.

Dr. Bilge Isik and others have been researching this material for at 
least 23 years, and a paper about it is here:
http://atlas.cc.itu.edu.tr/~isikb/yemenbildiri01.html 
<http://atlas.cc.itu.edu.tr/%7Eisikb/yemenbildiri01.html>
Also:
http://atlas.cc.itu.edu.tr/~isikb/Tech1.htm 
<http://atlas.cc.itu.edu.tr/%7Eisikb/Tech1.htm>

Other term for this material are Gypsum Adobe,  Composite Adobe, or 
Poured Composite Adobe, as referred to in this white paper from New Mexico:
http://www.angelfire.com/nm2/swdesert/whitepapercompositeadobe.html

So, the limestone on your property can be an asset if you're willing to 
go this route and do further research. I for one won't blame you if you 
pass on this since using the material is both time consuming and 
relatively hard physical labour.
However, you could test the stone to see how difficult it might be to 
form trenches for footings, etc. in. A decent handsaw might cost $25. A 
decent dust mask would be advised, as well...

You can also drill into the stone and use a "non-explosive demolition 
agent" to crack the rocks into smaller bits. This is a type of 
silica-aluminum-based expanding grout which you add clean water to, mix 
like you're making cement mortar, then pour into the drilled holes to 
crack rocks. Some brand names for this material are: Bristar, 
Crackamite, and Dexpan

Bristar:
http://www.demolitiontechnologies.com/index.html

Crackamite:
http://www.crackamite.com/

Dexpan:
http://www.archerusa.com/products.html

Each of these links has How-to information and guidelines.

I presume there are other brands available as well.

In all cases, eye protection is necessary since the mix can expand 
rather quickly, and some can shoot out of the holes and hit you in the 
eyes.

When I looked into this type of material last year, a case of it costs 
around $150US, plus shipping, from one of the suppliers, but I don't 
know how far that case will go. This is cost effective for smaller jobs 
or ones close to buildings, where blasting with explosives is 
inappropriate.

Also, you don't need a ticket to work with explosives to use this stuff.

None of this might be of any use to you at this time, but the info may 
be worthwhile at some point.

Cheers,

Chris Green.