Added: 3 years ago
From: CornellCob
Views: 10,106
Sort by time | Sort by thread (beta)

Link to this comment:

Share to:

All Comments (11)

Sign In or Sign Up now to post a comment!
  • dude, can i come visit you to learn about cob in Cornwall later in the year?

  • I would love to see more Cob buildings in North Carolina, in as much as the material is dirt cheap, I bet the labor cost is high.

  • Thanks :)))

  • very educational. love the natural way of doing things..

  • superb :) cood be roof be made of cob(like doom) and whats the easyest way to make it water resistant?

    or cant be done?

  • Hi, I would hope that one would at least use a # 2 rebar (1/4 inch+/-) mat, 4"x4" spacing vertical and horizontal.

    WITH an expanded metal layer attached by tie wire. A maximum soil thickness of 8 inches and an absolutely impervious roof above. Let me know how it turns out!

    :D

  • @Mikdeelo you cannot and must not use metal inside a cob wall!! it will condensate and add moisture to the wall causing a failure overtime. Cob is the closest the comparison of concrete on the Newton scale, it works fine as is.

  • @TheDudeRulez09 Hello,

    The cob would readily wick away any moisture to condensate. The effect could never be likened to the stupidity of stuccoing over cob. Though a naked steel bar would turn to rust clear through, it could take decades. There are ASTM stds for zinc coated (galv.) and epoxy coated rebars, other countries have like standards. The question was whether cob could be used overhead. No doubt cob performs great under compression, rebar may prevent chance of catastrophic failure.

  • @Mikdeelo yes this is true but also being a natural builder I have seen first hand wallowed out areas of up to 3-4 inches that once held rebar, so I disagree with the wick away comment. now the zinc covered rebar might be the answer, I am very familiar with the astm standards as my good friend David Eisenberg helped to bring them into existence for cob and strawbale building. As for rebar preventing catastrophic failure, concrete has rebar and it continually fails, every cob shake test proves it

  • See the website 'flying concrete', for overhead construction techniques used in Mexico.

  • Water proofing, 'modified rubber' will outlast anyone alive to read this. Impermiable and elastic (lack of elasticity is a roofs main enemy) the stuff would eliminate care issues.

    No, I don't sell it, wish I did.

Loading...
Alert icon
0 / 00Unsaved Playlist Return to active list
    1. Your queue is empty. Add videos to your queue using this button:
      or sign in to load a different list.
    Loading...Loading...Saving...
    • Clear all videos from this list
    • Learn more