Cob: Clay & Bool walls >rockin' the cob wall

[Charmaine R Taylor]

Hi Snail man , the method of earth(cob) and rocks is very ancient...in Scotland
this method is called "clay and bool," the rocks are the bool.  The look is very
attractive, and heavy clay soil is used and the layers of rock and clay are built
up for house walls. Straw and sand may or may not have been addded, so the recipe
varies, but the walls are sorta like stone slipforming without the forms, and are
trimmed to create a straightish wall. Bools embedded in clay also look a bit like
cordwood...circles in mortar...and this type of building did have a roof over it
to protect from driving rains. I'd try it and put a little shingle style roof
over the wall top to see how it holds up.

(this info comes from  Historic Scotland- books on Earthen Construction.)
There is also a method of early rammed earth where 2 foot of soil is packed
between a facing of fieldstones, much like the idea you are describing, only
wider walls.  the walls were highly insulative, and were called Black
Houses...mostly because fire pits inside let smoke filter thru thatched roofs,
thus blackening everysurface inside. ( no windows  used in the
cold/harsh/rain/wind environment)  There was little to no wood, so everything was
constructed from soil, rocks, thatch materials.

Also papercrete can be plastered over with cob and rocks, thus making a fast
built wall which can be poured ( the papercrete part), once fairly dry, plaster
that puppy with clay/cob.   I like the IDEA of papercrete.. but you are not
limited to just paper..I use sawdust, clay and lime to make "cobwood" a pourable,
sculptable mix. more earth friendly, ssaawdust is plentiful here locally, and
lime stabilizes the clay, makes a natural cement

Goes up fast, can be shaped, dries faster, and uses no cement. tada!  Almost free
and easy to do.


 Charmaine  Taylor
Taylor Publishing
PO Box 6985, Eureka CA 95502
1-707-441-1632
http://www.northcoast.com/~tms



SNAILHUNTr at aol.com wrote:

> so what does everyone think about the method of rock pushed into the exterior
> of a cob wall to decrease erosion?