permaculture

["John Schinnerer" <john@eco-living.net>]

Aloha,

Thanks for the additional info, Gene.  Points taken - masonry units are
not good for propping anything up, I first heard that about working under
cars...hadn't thought about the point stress from irregularities but it
sure seems obvious when you point it out.

Rob Roy does specify some vertical rebar-and-grout fill, btw, not just the
dry-stack and surface bond and nothing else.  Also, he's working with
small dwellings, nothing big, so I suspect for that app it is plenty
strong.  His take is that mortar masonry is a bit of a steep learning
curve and dry-stack with surface bond and vertical fills is a whole lot
easier for the DIY owner-builder of a small earth sheltered dwelling. 
He's built a number of 'em and no problems in terms of wall strenght - and
he's pretty up front about problems and learning experiences he's had with
his various methods.

I'd slide the blocks against each other a few times and give a quick
brush-off to get more surface contact, that would help some I'd guess and
not add too much time to the stacking.

> A little more on surface bonding cement....

John Schinnerer, MA
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