Cob Yoda's cob house

[Will Firstbrook WCB of BC]

Hi Shannon,

Thanks for your reply!

>-----Original Message-----
>From:	Shannon C. Dealy [SMTP:dealy at deatech.com]
>Sent:	Thursday, December 04, 1997 12:43 AM
>To:	'coblist at deatech.com'
>Subject:	Cob Yoda's cob house
>
>[Will Firstbrook  WCB of BC]  snip
>
>I have no doubt that a cob dome roof can be safely constructed using
>corbelling, as long there is sufficient arch to the dome.  It is
>important to remember that when you build an arch or dome, much of the
>force acting on the materials are compressive rather than tensile or
>shear forces, and compressive strength is where cob excells.  My concern
>with using cob for any kind of roof is that should there be any failure of
>the roof's protection from the weather, it might kill somebody before you
>are aware of the problem. 
>
>[Will Firstbrook  WCB of BC]  
>Yes, that would concern me big-time. This project must be people friendly as
>well as earth friendly.
>  
> Personally I would consider this to be to much
>of a risk to take, though it might be reasonable to try cob arches as your
>roof support.  If you want to achieve the yoda effect, I would go ahead
>with the cob walls and sculpture work, but then put a small geodesic dome
>on the top to give the rounded roof structure and plaster the interior of
>the dome with cob to keep the interior effect.  You would still need to
>have wide eaves around the outside to protect the cob walls however.  If
>you really want the dome effect inside and out, you might be better off
>just building an inexpensive geodesic shell as your entire exterior and
>use cob for the interior.
>
>Shannon Dealy
>dealy at deatech.com
>
>[Will Firstbrook  WCB of BC]  
>I have to so some serious thinking about this room as I want to make sure
>that it is safe, doable long lasting and low cost. Maybe I should build this
>room into the ground and build a more conventional living roof. But from the
>inside it looks like yoda's house with corbeled arches and roundish windows.
>
>Thanks for your input.
>
>Regards, 
>Will