Cob: Re: foundations, tree roots

[Kerry S Tebbetts]

Thanks, Rick, for sharing your experience.  You said the "circumference"
is 10-12 feet?  Did you mean the diameter because if the circumference
was 12 feet, then the diameter would be about 4ft or  about 48in.  Maybe
it's possible that 110 yrs ago the diameter of the trees was only 15in
which would put them at a safe distance from the excavation for the
foundation.  This would be assuming that the trees grew on average 1/3in
per year, and since I have no real knowledge of the growth rate of oak
trees in various climates, I'm only half speculating and pondering
another possible explanation.  Although with that said, I'm surprised
that tree roots haven't invaded your foundation yet.  

shae

On Sat, 27 Apr 2002 10:30:58 -0500 "Rick Fisk" <rfisk at ev1.net> writes:
> 
> I wonder if the "conventional wisdom" is in error or is recommended 
> due
> to the habit of builders to use a bulldozer in order to 
> over-excavate
> the building site.
> 
> I live in a house built from rock, quarried from this location,
> constructed in 1890. The two live oaks which surround the house are 
> less
> than 15 feet away from the foundation and are 500 and 300 years old
> respectively according to arborists who have examined them. The
> circumference of the trees are at least 10-12 feet each which, if I 
> am
> reading correctly (1 foot away for every 1" in diameter) would mean 
> that
> the foundation would have to be almost 100 to 120 feet from the base 
> of
> the tree.
> 
> There isn't a lot of topsoil here and there is a great deal of 
> limestone
> on this site barely 3 feet under the surface.
> 
> If constructing a foundation so close to the trees cause 
> irreparable
> damage to them, you would think these two enormous oaks would have 
> died
> 100 years ago. I'm sure that one has to be careful but perhaps not 
> as
> extremely so as is suggested. And perhaps the type of foundations 
> and
> excavation required to build a cob house (rubble and stone trenches
> seems to be the favored) is not nearly as intrusive as the huge
> excavations required for the traditional house.
> 
> Rick
>