Cob: Cob insulation idea

[lightearth at onebox.com]

We haven't had any problems plastering over and around the ends of wood as they key in quite nicely...UNDERSTAND...we are NOT using cordwood and then plastering over it, our 'Cob Scrap' is the ends of 2x4's and similar construction waste (any non-treated kiln-dried lumber)set in the walls like Cordwood so our goal is to plaster over the whole wall leaving an earthen-plastered wall....

the 2x4s etc. are to:
a)use alot less Cob (and still make a incredibly strong wall- but fast!)
b)tie the inner and outer walls together(we insulate between)
c)provide a decent thermal break (good R according to Darel's calc.) d)provide 'deadmen' in the wall for attachment points for screws 
e)reuse the horrendous amounts of cutoff lumber in the dumpsters around us that go to the landfill 
f)be a non-toxic, very (already) dry-cordwood material that doesn't require much processing....

Rob Roy is right about not covering up the ends of natural wood and we even started out our Cob Scrap projects with the idea of setting them to the outside of the walls and then decided that they'd only look good if we arranged them in patterns, which we might still do, but thought that this took away from the speed of buiding...you COULD arrange the 2X4's into a pattern in places, leaving them exposed, and even paint the ends for a sunburst effect or something - worth a try!


Marlin



<snip>
Hi Marlin, how is plaster doing over the wood ends? I asked Rob Roy of the
Earthwood Building school how plaster would work over the cordwood (with cob
mortar) and this was his reply: dont know about clay plasters over cordwood.
People do it all the time with ordinary cement plasters, with good results.
I think that it is worth a try. Worst case is that the plaster cracks and
falls off. The endgrain of the wood might rob the moisture rapidly from the
clay plaster and the rapid drying might be detrimental. You could be the
first to do it! (I guess not-jen)  But don't cover it all. The main thing
about cordwood masonry is that it is beautiful. Rob

Just wonderin'
Jen