Cob: Re: Foundations, tree roots

[toswink]

Also roots go for water.That should not be the problem since the house would
block the water.

 Another thing is that if you follow your county extension agent ways to
fertilize your tree the root should go to that reather than under homes.
also.

 In hydroponics we discovered corn could grow in eight inch round flower
pots  since thier roots would not grow unless they had not enough water and
nutrients. They were supported by a single string from the roof.



----- Original Message -----
From: "John Fordice" <otherfish at attbi.com>
To: "Kerry S Tebbetts" <yourelovedbygod at juno.com>
Cc: <coblist at deatech.com>
Sent: Saturday, April 27, 2002 9:45 PM
Subject: Re: Cob: Re: Foundations, tree roots


> Kerry,
> Not being an expert on trees, I'll speculate to say that if you build so
> as not to compromise an existing root system, whatever growth the tree
> does after your building is there will be adapted to the then existing
> soil situation.  If the tree's growth future is limited by the fact that
> your building is where it is, then the tree will not grow in a manner
> that will cause damage to itself.  This is different from an act of
> construction damaging an already existing root system & hence causing
> damage to the tree depending on those roots.
>
> Re your wondering about a foundation on the surface of the ground in
> lieu of an excavated foundation.  The reason for excavated foundations
> is to assure that the weight of the building ( which is considerable in
> the case of a cob building ) sits on " competent " soils.  It is quite
> possible that the upper portion ( i.e. topsoil ) has some give to it &
> will subside some when subjected to the weight of a building.  In
> general, this gets to be less the case the deeper you go into the
> ground.  The building code assumes that at 12" of depth the minimum soil
> bearing capacity is 1000 pounds per square inch.  At a depth less than
> this, it is generally not wise, in the absence of other proof, to assume
> the soil can successfully support your building.  If you calculate the
> weight of your cob walls at 150 pounds per cubic foot for the whole
> height of the walls including your foundations and set your footing
> width accordingly so as not to exceed 1000 psi at the bottom of a 12"
> deep footing. the buildings walls will ( according to the building code
> at least ) be adequately supported by the soil upon which they sits.
> This does not take into account the loads of any associated floors or
> roofs of course.  If the wall is carrying any other such loads, they too
> should be taken into consideration when deciding the necessary
> foundation width.
>
> john fordice
>
> Kerry S Tebbetts wrote:
> >
> > Well, the problem is that the drip line will get bigger once some of the
> > smaller trees are thinned out to make room for the house.
> >
> > On Sat, 27 Apr 2002 11:42:51 -0700 John Fordice <otherfish at attbi.com>
> > writes:
> > > An arborist once told me that the roots of a tree will be a bout the
> > > same area as the branch spread.  The limit of concern so as to not
> > > compromise the root system is don't excavate or build or put
> > > impervious
> > > paving anywhere inside the drip line ( outer circumference  ) of
> > > the
> > > branches.  This was in discussion about protecting some huge oak
> > > trees
> > > in the Napa Valley.
> > > john fordice
> > >
> > > Rick Fisk wrote:
> > >
> > >
>