Cob: cob over traditional house?

[Julianne Wilson]

OK - here's a twist on that idea - what about a cob encasement for a metal
structure - like a 30 year old mobile home????
any thoughts (suggestions, warnings, etc!)
Never occurred to me that this might be a possibility until now......
Thanks
Julianne

on 10/31/02 1:35 PM, John Fordice at otherfish at attbi.com wrote:

> Melanie,
> I don't see why you could not encase your old farmhouse with cob so long
> as you studded the building with nails to create a mechanical bond
> between the house and the cob.
> 
> I do see some potential problems though:
> 
> Any cracks that might occur due to the shrinking of the cob over an
> object ( the house ) that is not going to shrink along with the cob as
> it dries will leave a pathway for rain to enter & it might create dry
> rot potential.  A very high sand component will help reduce shrinkage &
> might limit this potential.
> 
> The eave width of your existing roof might need to be made wider to
> protect the cob from falling rain & roof edge run-off.
> 
> The biggest concern I'd have is the added load and it's possible seismic
> implications.  Wood construction ( I assume the house is wood framed )
> has developed to resist the loads of a wood building.  Cob is much
> heavier & unless a cob building is properly designed and built as very
> thick walls,  it does not have much seismic strength.  Placing a layer
> of cob on your building that is not thick enough to support itself in an
> earthquake could overload the bracing of a wood framed building & cause
> a dangerous situation with the possibility of failure of the building in
> an earthquake.  Don't be lulled into thinking this is not a problem if
> you are not in earthquake country.  Earthquakes can potentially happen
> anywhere on the planet.
> 
> john fordice
> 
> Melanie Kleiner wrote:
>> 
>> I was wondering if it is possible to apply cob over an existing old farmhouse
>> (it has that nasty asbestos slate siding now).  There are many cracks and
>> drafts and I thought it might be a less expensive way to reside the house.
>> Plus I love the look of cob and we could add on to the house with cob.  Any
>> thoughts are welcome!
>