| A sustainable system generally
can be defined in environmental terminology as
a living system which continues by virtue of the fact
that it does not use up resources faster than they can
be naturally replenished. In economic terminology,
a sustainable economic system is one in which the expenditures
are at least equal or less than the income. In social terminology, a sustainable social system is one in which
all members are empowered to contribute, creating a synergistic
whole. These separate definitions are inextricably intertwined
and interdependent at all scales, from an individual 'body',
to a family 'body', a community 'body, a regional 'body',
a national 'body', to an international 'body'. It is increasingly
clear that decisions made on a personal level have repercussions
on the global scale as well as the reverse.
In the United State alone, the use of virgin raw materials
was 14 times greater in 1991 than in 1900 while the
population increase was only 3 times. Most growth occurred
with new homes, roads, stores and offices in the 1950's.
Between 1945 and 1973 the U.S. paper and industrial
minerals consumption more than tripled; metals more
than doubled; plastic consumption increased a whopping
35 times. Too much of this ends up in our landfills.
Studies show that 20-25% of the U.S. municipal waste
stream is from building construction or demolition.
It is also becoming increasingly clear that the building
and construction industries have played an ever increasing
part in impacting all aspects of life: environmental,
economic and social. Buildings in the United States,
in their production and use, consume an estimated 40-65%
of our national energy total. Globally, it is estimated
that buildings currently account for:
- 1/6th of the world's fresh water use
- 1/4th of all wood harvests
- 2/5ths of all material flows
- 2/5ths of all energy flows
By using more efficient building methods and materials,
it is also estimated that we could reduce the energy,
resource consumption and / or waste production by 50-60%
without decreasing value, aesthetics or function. With
the understanding of the Earth's finite resources and
the knowledge that manufactured products, including all
building materials, have an effect on our resources, it
is becoming increasingly important to make wise decisions
regarding the use of these limited resources to protect
our environment and our ability to sustain ourselves.
The design and construction industry is in a position
to effect change in building practices through the use
of resource efficient construction materials and methods.
The barrier to the use of such materials is most often
the lack of the information about availability, cost and
a means of evaluation.
This guide is intended to be a design tool for using
an expanded list of criteria in the selection of building
materials with the goal of creating sustainable environments,
economies and societies.
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