RE: [GBlist] re: truly sustainable

["David Wagner" <dwagner@sa.kevric.com>]

Well, I agree with the durability and reworkability of a structure
being critical to the 'greenness' of a building material.  If you have
to replace your home every twenty years, the materials must be better
than 1/10 the impact of the materials used to build a structure to
last 200.  Let me see if I can break this down for a timber and stone
building.  I won't get the numbers right, but perhaps others can
correct these assumptions.

Let's say killing one tree 200 years old will give me enough timber
for 1,000 square feet or 10,000 cubic feet of a generic timber-frame
and stone structure which will last 200 years.  (Again, these numbers
are guesses, subject to correction by someone who knows more than I.)
If an ecosystem can spare it, I could have the tree chopped down, so
long as I replace it.  To guarantee its replacement, I will have to
find, purchase, and place a conservation easement for 200 years on
1/10 acre of land in need of a tree, contiguous with an existing
protected forest ecosystem, enough space to plant 2 trees, one of
which is likely to live to 200 years.  This tree was sinking
atmospheric CO2, producing oxygen, and filtering water until I cut it
down, and the seedlings won't be up to its capacity for quite a while.
So, I owe everyone some CO2 reduction and some oxygen to breathe, and
I owe the community near the tree a bit of fresh water.

Let's say I also choose fieldstone.  I will also need to acquire the
mineral rights for a parcel large enough to heave up the amount of
stone I need, and protect it with some legal provision to prevent
mining for long enough to do so.  If the land beneath those trees is
not enough, I may need to add some.    That covers the costs of
acquiring these materials.  (I think; please add comments.)

There are also some other benefits.  Besides gaining the dead tree, I
have protected at least 1/10 of an acre of forest ecosystem.  Since I
try not to be greedy, I'll donate it to a nonprofit organization to
preserve as public land (with the easements in place and mineral
rights secured against use by anyone for a very long time, of course).

Now there are similar things to do to completely account for the
processing and transport of these materials.  I am likely to find I
cannot possibly afford transporting fieldstone from under those trees
and compensating for the environmental impact of this folly.  I am
also personally of the opinion right now we need a few centuries of
forest restoration before consuming any more timber, but just because
this is my opinion does not mean we cannot reasonably consider timber
costs when forests are restored and can be harvested sustainably.
But, back to this analysis.

There are limestone quarries in my area.  What are the costs of
removing, say, one ton of limestone?  How must I compensate?  When I
finish the whole building design, is the total cost to me something
six billion other people could do limited by the resources of this
planet?  If not, I need to look very hard at my design and my choices
of how and even where to live.

As for labor, I agree it has very high value, and do not plan to
translate it immediately into local currency, but to account it as
hours of a particular skill, for example, 1 hr time cost to the
sawyer.  What the sawyer will accept as fair trade in exchange for
this hour is negotiable, but I think $20(US2000) is a reasonable
default value for the time of a US citizen.  (This is double the
$10/hr living wage advocated, since my own personal opinion is we
should be compelled to work for others at most 20 hours in a week.
Again, if there is enough interest and information to get an analysis
system like this online, people will be able to change the default
assumptions when they use it.)

Does anyone else think this is a useful exercise?  Could it be?

-David


In response to what Chris Koehn wrote:
> Here, we have lots of wood, and in
> my immediate
> area lots of field and quarry stone. While our area wasn't
> settled until the
> early 1800's, the examples of structures which have endured
> the past 150-200
> years are almost all timber and stone. One can, of course,
> argue that those
> are the materials the settlers were used to working with and
> really the only
> substantial materials available then. But we can also look to
> the places
> these settlers came from, which often had similar climates
> (and, in the case
> of much of Europe, a depleted wood resource, due to
> over-use..). Wood and
> stone were the materials of choice there, and indeed when I travel
to
> northern Europe I see that these are the buildings which
> endure. Certainly
> other organic materials were available- my supposition is
> that if they were
> used they have not survived the test of time in nearly the
> numbers that
> timber and masonry structures have.
>


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