Cob Bond Beam?

[Speireag]

Howdy, all.

    I was just poring over the messages on the cob list when suddenly an
idea popped up.

    Many straw bale builders use a concrete bond-beam at the top to level
things out and hold things together.  What would be the difficulties with
making that bond-beam from cob, instead?

    I see one:  not quite as easy to level, because you couldn't screed it
flat.

    Does cob have enough strength in tension?  Could you reinforce it with
rebar to achieve the same result which rebar does in concrete?  Would the
cob resist the flexion produced by further uneven settling?  Concrete
appears to do so; why?  Because of the rebar?  Does concrete crack anyway,
a little bit, but it's under the eaves and so doesn't matter?

    Taking this idea a bit further:  what about building a straw bale wall,
post-and-beam outfill, and using cob to take up the spaces which you can't
manage to stuff adequately with loose straw or partial bales?  I have in
mind especially the space between the highest run of straw bales and the
rafters.

    Awaiting reactions with bated breath...

-Speireag.

0>>>>>>(---------------------
Speireag, aka Joshua Macdonald Alden (speireag at linguist.dartmouth.edu)
Usually found somewhere in the wilds of New Hampshire.
Ma 's e bhur toigh le, sgrìobh sibh dhomh anns a' Ghàidhlig
 agus tapadh leibh airson mo Ghàidhlig a cheartachadh.