CHAPTER SEVENTEEN

RICHARD A. TRACY

SUSTAINABLE BUILDING MATERIAL TRANSITION IN THE UNITED STATES: 

TOWARD A SUSTAINABLE FUTURE
Not so long  ago Buckminster Fuller reminded us that we are all travelers 

on Spaceship Earth.  Since that time there has been a growing concern and 

awareness about how we manage the natural environment and resources 

within that environment.  One need only look at the increase in fuel 

efficiency in automobiles to see evidence of this trend.  Evidence of 

this trend may also be found in the building industry.  That industry is 

constantly looking for new technology to save energy.  The explosion in 

the number of materials with increased insulative capacities is just one 

example of this search for better technology.

     It is important that planners, architects, engineers, builders, and 

governmental bodies realize the necessity for responsible use of natural 

resources.  The building industry uses these resources in both the 

construction and the operation of buildings.  In addition, the industry 

uses vital resources at the end of the life of a building.  These 

resources are used for the demolition and disposal of materials from a 

building.  As fuller reminded us, we are part of an intricate system.  

That system has its limitations and advantages.  Some of the resources 

within the system can be regenerated, some cannot.  

     While it is important to understand that technology plays an 

important role in the building industry, it is equally important to 

realize that money may play an even bigger role.  Clearly these new 

technologies come at a cost to the consumer.  Thus, in addition to the 

building industry's responsibility, there is a large measure of 

responsibility placed on the consumer.

     It is the focus of this paper to deal with the issues of resource 

use in the building industry.  Specifically, this paper will deal with 

the topic of renewable and nonrenewable resources as they apply to the 

materials used for the structure of buildings.  Of interest are the 

choices people in the United States make with regard to the way they 

build in the context of the environment as a whole.  Of particular 

interest is the comparison of the impact of traditionally popular 

methods/materials of construction and "Green" or "Sustainable" 

methods/materials of construction.

     It may be of some great use to define sustainability in terms of its 

use within this paper.  In this paper sustainability is best defined in 

the words used by the Rainforest Action Network to define sustainability 

for their home page on the World Wide Web.  "Sustainability is when the 

functions and processes of an ecosystem can be maintained (or sustained) 

while the needs of the present are met without compromising the needs of 

future generations."(Rainforest Action Network, 1995)

     This notion of sustainability has a great deal of importance in the 

discussion and evaluation of new technologies.  There are many new 

building materials and methods of construction developed each year.  What 

is important to evaluate is not just the performance of these materials 

and methods, but the impacts these materials/methods have on the 

environment.  The manufacture of new materials can have profound 

ecological ramifications.  Too often these ramifications are not weighed 

in the overall evaluation of new materials.  The example of asbestos 

insulation comes to mind.  We are now faced with finding ways of removing 

and disposing of a health threatening material used in hundreds, if not 

thousands, of buildings here in the United States.  It is now clear that 

the costs of manufacture, removal, and disposal (or recycling) of 

building materials must be taken into account when evaluating building 

materials.  Another cost to consider is the cost involved in developing a 

sustainable replacement.



Life Cycle Assessment

     At this point it is useful to bring up the issue of life-cycle 

assessment.  Life-cycle assessment is a means of  applying a 

"cradle-to-grave" or "cradle-to-cradle" approach to looking at buildings 

and building materials.(Wilson, 1995)  In other words, it is looking at 

buildings and their components from their origins to the eventual demise 

and/or the potential reuse of specific components or the building as a 

whole.  How are materials obtained?  What types and amounts of 

pollutants, if any, are given off during manufacture?  Are there health 

concerns during manufacture, installation, use or disposal?  What happens 

at the end of the material's useful life?

     It is important to note the difference between life-cycle assessment 

(LCA) and life-cycle cost analysis (LCCA).  "Life-cycle costing applies 

economic principles for the specific purpose of improving design and 

management of resource allocation decisions by considering the total 

long-term costs of facility ownership."(Johnson, 1990)  In other words, 

life-cycle cost analysis allows us to consider purchase, operating, and 

maintenance costs of a piece of equipment.  This enables one to make the 

choice between several options and potentially justifies the selection of 

an initially more costly system, such as compact fluorescent lights, over 

an initially cheaper alternative, such as incandescent lights.  The key 

difference being that LCCA takes into account only traditional economic 

factors.  Brandle (Brandle, 1995) expresses the following concerns:

"1)  The prices of nonrenewable resources are low.  They do not reflect 

the real costs, only the production and marketing costs.  The costs of 

depletion are not included.

 2)  The burden of paying for inefficiencies and waste, mostly as 

pollution, is often not carried by those who cause it.  This is most 

evident in the difficulties of assigning responsibility for the pollution 

of air, water, and earth.

 3)  The dangers from depleting nonrenewable resources and the benefits 

from using renewable resources for overall society are not well 

understood by the general public."(Brandle, 1995)

     It is apparent that some form of ecological currency is necessary.  

Some have argued that ecological currency is a part of economic 

currency.  These individuals usually point to the example of gasoline.  

Currently gasoline prices in the United States hover somewhere around $1 

per gallon.  In the United Kingdom the cost is over $2 per gallon.  In 

Italy the price is nearly $4 per gallon.1  In his course Energy, Entropy, 

and the Environment, Rycus argues that as accessible reserves are 

diminished the cost of oil will increase.  This price increase, in turn, 

is evidence of ecological 

currency being a factor of economic currency.  However, Rycus is quick to 

point out that the point at which this price increase begins to affect 

the general populace's thinking and buying habits can be at a point 

beyond that of sustainability.

     It is evident that some means of translating ecological cost into 

economic costs at earlier stages may be necessary.  However this is not 

without certain risks.  Classical economic theory holds that correct 

prices are an essential factor for maximizing economic benefits.  Some 

may argue that this may also hold true for prices reflecting the truth 

about external costs.  This does not necessarily hold true at all times.  

Unforeseen or abrupt changes, even for the better, may cause massive 

upheavals and economic losses.  The painful restructuring of the 

economies of Eastern Europe are a good example of this.(Dutch Committee 

for Long-Term environmental Policy, 1994)  Great care must be taken in 

introducing ecological costs at earlier stages of the proposed building 

materials transition.

     One can also see that it is necessary that better systems of 

accountability for pollution should be devised.  Those parties wasting 

materials should bear the burden of doing so.  This burden should also be 

heavy enough so as to encourage the reduction, if not the elimination, of 

inefficiencies in material usage.

     It is also apparent that the general population should be made aware 

of the dangers of depleting nonrenewable resources.  As the general 

population in the U.S. elects the officials who control many resource 

management policies, the education of the general population would aid in 

obtaining governmental officials who are sensitive to the very same issues.

     Another pitfall of conventional life-cycle cost analysis is that it 

traditionally considers the life of a building to be 20-40 years.  There 

are wood structures all across the United States with ages exceeding 100 

years.  Within the confines of conventional thinking a building becomes 

disposable after a 20-40 year lifetime.  This is somehow appropriate 

coming from the land of disposable diapers.  This type of thinking cannot 

exist if sustainable development is to occur.  Greater attention must be 

given towards the adaptive reuse of structures.  

     In addition to the reuse of structures, Brandle (Brandle, 1995) 

encourages the exploration of design for recycling.  He states, "the 

concept of recycling must become as much a part of building design as the 

other concepts of design that we are so familiar with, such as functional 

integrity and aesthetic appearance."(Brandle, 1995)  He points to the 

work of the German auto manufacturer BMW as an example.  BMW is pushing 

for as near complete recyclability of an automobile as possible.  They 

are literally designing some of their cars for disassembly.  Brandle 

points to the obvious transfer of this type of thinking into building 

terms.  He points to the graduate level design studio he recently 

conducted as an example of this type of thinking.  Students were 

encouraged to design such structural systems as pre-cast concrete panels 

with bolt connections to enhance the reusability of these elements.  

Traditionally these systems are connected by welding or site-cast 

concrete joints.  These types of joints make recyclability very tenuous 

at best.  Brandle also encouraged students to specify components made 

from recycled wood, automobile tires, and aluminum or steel.(Brandle, 1995)

     Life-cycle assessment is clearly necessary.  It will develop 

somewhat differently than traditional life-cycle cost analysis.  Though 

LCA may development differently than LCCA its development is necessary 

for both sustainable design and for the successful building materials 

transition proposed by this text.



Conditions and Trends

     Over the years building construction methods  in the United States 

have gone through a series of changes.  Early methods used timber framing 

for structural support.  Later, brick and stone were used.  Then came an 

interesting system called "balloon framing".  This system uses a series 

of repeated small dimensional structural members.  This method has been 

popular for quite some time.  The major application of this building 

system has been in the arena of housing.  It appears that this method of 

construction became popular for several reasons.  First, with increased 

population the supply of stone and brick materials was too small to meet 

building needs.  Secondly, the new system of building was less 

economically expensive than the prior systems.  However, recently there 

has been a trend away from this system of building structure.  The use of 

steel and pre-engineered wood structural products seems to be increasing.

   It appears that the United States is in a transition of building 

materials.  As mentioned above, one of the options is steel.  Another 

option is pre-engineered wood products, some of which use recycled wood 

materials.  As prime dimensional lumber is used up, there may be an 

increased use of laminated and recycled wood chip products.  The 

following two graphs show and project the growth of roundwood production 

and the decline of steel production.

 

     From the two graphs (graph; next graph) one sees a steady decline in steel usage and a 

steady increase in sawnwood production.  This is somewhat different than 

what is occurring in the architectural world today.  Presently, in some 

markets in the U.S. it is cheaper to use residential scale steel 

structural members than it is to use wood.  This is an alarming trend 

when put in the total ecological context.  Steel is a nonrenewable 

resource.  We should carefully consider how we use this resource.  In 

light of the more environmentally friendly option that engineered wood 

products offer, the application of steel on the residential market seems 

a bad move in the long run. 



 

     The graphs bear witness to the economic pressures put on the 

market.  With decreasing steel production the demand appears to be low 

and the price must therefore be low.  With the steadily increasing 

sawnwood production we see an increased demand and an increased price.  

Current national average prices bear out this line of thinking.  As an 

example, a typical wall assembly consisting of 2x4 stud with 5/8 fire 

resistant drywall on both sides of the stud costs roughly $2.98 per 

square foot of the wall assembly.  A comparable assembly substituting a 

35/8 metal stud for the wood member costs roughly $2.80 per square foot 

of the wall assembly.  However, we should also bear in mind the 

ecological as well as the economic costs involved.



Building Materials

       At this point it may be useful to discuss the definitions of some 

of the terms that will be used frequently in this paper.  First among 

these terms is "dimensional" lumber.  Nearly everyone has heard of a 

"two-by-four".2  This is a piece of wood with nominal dimensions3 of two 

inches thickness and four inches width producing a simple rectangular 

cross section.

     The same follows for other pieces of dimensional lumber: 2"x6", 

2"x8" and so forth.  The largest pieces used in typical house 

construction are 2"x12".  These are used primarily for the support of 

floors on long spans.

     Traditionally, these pieces of wood were cut from the large, old 

trees of the forest.  These trees yielded better quality lumber than 

smaller, faster growing trees.  In addition to quality there is also the 

factor of quantity.  The larger the tree cut for lumber is the greater 

the dimension of the lumber cut from that tree.
Two-by-four cross section
Glue-laminated timber

                     

     Once spans stretch beyond the capacity of a 2"x12" a different type 

of lumber may be necessary.  This type of lumber is the glue laminated 

timber.  This type of lumber is constructed of a series of 1.5" wood 

laminations.(Wright, 1994)  

                        

This type of structural member can be manufactured in a variety of 

different sizes to fit various spanning conditions.  These timbers are 

manufactured under tightly controlled conditions.  Another important type 

of wood based building product is LVL or Laminated Veneer Lumber.  This 

type of lumber generally consists of a series of thin wood layers affixed 

to one another with a resin of some sort.  The fibers of each layer can 

be oriented so as to give the structural member the greatest strength.  

LVL construction is similar to plywood except that the grain of alternate 

layers is not oriented at right angles to that of adjacent layers.


Laminated Veneer Lumber
This type of lumber can be manufactured in any number of sizes.  It can 

be used similarly to plywood and is an important component in the next 

type of wood structural member.  Again, this type of lumber is 

manufactured under tightly controlled conditions.

     The next type of wood structural member is the wooden I-joist.  This 

element, like LVL is manufactured under rigidly controlled conditions.  

It consists of two flanges made up of a series of 1/10-inch wood veneers 

or stress-rated (high quality dimensional) lumber.  The other component 

of I-joists is the web which is commonly made with plywood or oriented 

strand board (OSB).  Oriented strand board is a panel type material made 

from wood strands that have face wafers oriented in the long direction to 

provide additional strength in that direction.(Wright, 

1994)
OSB/Plywood Web
     One may ask why it is important to manufacture the above mentioned 

elements under tightly controlled conditions.  The answer lies in the 

fact that when these controls are in place, the load bearing capacity of 

the member can be more precisely determined.  This allows for a savings 

in the amount of wood materials used.  With traditional dimensional 

construction only "mother nature" controls the production of the 

materials.  The load bearing capacity of a member can thus vary 

significantly from one 2"x4" to the next.  This then requires a large 

margin of safety in the structural design process and leads to a greater 

degree of overdesign of the structural systems.  Clearly this has an 

environmental impact.

     The last structural building element this paper will deal with is 

the metal (or steel) stud.  This is a piece of metal, usually a roughly 

hollow tube-like construction, that is often used in place of traditional 

dimensional lumber in wall assemblies.  The load bearing capacity of this 

type of material is even better known than the manufactured wood products 

mentioned above.  Thus these elements can be used with even greater 

structural efficiencies.  This type of material is seen as a significant 

competitor to wood.  Such thinking could have serious repercussions on 

the environment.  In addition to being a nonrenewable resource steel is 

also a good conductor of heat.  The application of steel/metal members in 

an exterior wall structural system leads to an increased loss of heat 

through the buildings skin.

     Engineered wood products have a few drawbacks.  They pose potential 

off-gassing hazards as well as potential chemical pollution from their 

manufacture.  This leads to potential health and ground water problems.  

In the past one of the biggest pollution problems was the use of 

formaldehyde as part of an adhesive in manufactured wood products.  The 

use of this material is being quickly phased out.  In fact, some of the 

newer products use a process or pressing wood scraps under great pressure 

to form a beam.  The pressure and resultant heat release chemicals in the 

wood scraps that form a binding agent.

     Pre-engineered wood products have some potential benefits as well.  

First, as mentioned above they can be made using recycled wood 

materials.  A quick look at construction site waste is very telling.
Survey of Construction Waste (GBB, 1995)
Concrete         32.9%
Dimen. Wood      15.1%
Roofing          9.6%
Metal            8.8%
Other            8.1%
Cardboard        7.5%
             

Brick            6.7%

                                              

Drywall          6.6%

                                           

Pallets          2.6%

                                           

Asphalt          0.6%

                                           

Plastic          0.5
Plywood          0.5%
Clearly dimensional wood is one of the top contributors to construction 

waste.  It is estimated that as much as 11% of traditional lumber may be 

thrown away on job sites due to poor quality.  When engineered lumber is 

used that number drops below one 1%.(Wright, 1994)  The use of  finger 

jointing this scrap wood, formerly put into landfills or burnt for fuel, 

into larger pieces is a viable solution to the waste problem that leads 

to an additional saving of wood.(Loken, Miner, Mumma; 1994)  

     In addition to the waste at the job site there is waste at the 

manufacturing site of all wood products.  One company, Trus Joist 

MacMillan, claims that its manufacturing process for engineered wood 

I-joists converts 43% more of a log into structural lumber than does 

solid-sawn (dimensional) lumber.(Wright, 1994)  Traditional sawmilling 

converts 40.6% of any given log, by weight, into dimensional lumber.  

Trus Joist MacMillan says that its process converts 58% of a given log 

into its TJI/15 joists, in addition to yielding a small amount of 

plywood.(Wright, 1994)  It is apparent that some headway is being made 

towards the more efficient use of our forests.

     Secondly, engineered wood products can provide structural lumber 

from fast growing, small trees.  This would add great value to the 

smaller diameter trees of second and third growth forests.(Loken, Miner, 

Mumma; 1994)  With a dwindling supply of straight, dimensionally stable 

heartwood it may be argued that builders will turn, more and more, to 

other options such as engineered wood and metal products.

     Finally, engineered wood products allow for a greater efficiency in 

structural design.  This directly translates into a savings, both in the 

number of elements used per project versus dimensional lumber and less 

lumber per element versus dimensional lumber.  That  means that not only 

are you using fewer pieces of wood, you are using less wood per piece.

     At this point it may be of particular use to look at a series of 

transitions that affect and interact with the proposed building materials 

transition.  The other transitions examined will be the demographic 

transition, the forestry transition, and the urbanization transition.  

Each of these transitions has potential consequences for the building 

materials transition.



Demographic Transition

     Drake (Drake, 1993)characterizes the demographic transition as 

follows.  At the onset of the transition the numbers of births and deaths 

are high and are in relative equilibrium with each other.  During the 

transition death rates drop dramatically.  After a period of time the 

birth rates begin to fall.  If these two rates track on another then 

growth may be significant, yet manageable.(Drake, 1993)  The graph below 

roughly shows the crude birth and death rates tracking one another.  

Clearly, the United States is in a period of relative equilibrium 

following a demographic transition.  The U.S. is in a position of 

manageable population growth and thus has some hope of being able to 

sustainably manage its natural resources.  If the birth and death rates 

do not track one another there can be a population explosion.  The second 

graph below shows the birth and death rate for Africa.  Clearly Africa is 

in the midst of a demographic transition.  Africa has little hope of 

being able to sustainably manage its natural resources while it is in the 

grip of a demographic transition.


Crude birth and death rate for the United States
 It is important to note that all data in the graphs beyond 1995 is 

projected.

     What impact does this have on the proposed building materials 

transition in the United States?  One obvious relationship is drawn from 

the population.  A greater population size means a greater usage of 

resources.  More specifically, a greater number of buildings are built 

and thus more steel, concrete, wood, and other materials are used.  This 

puts a direct stress on those resources.  With a manageable population, 

i.e. one that has gone through the demographic transition, there is hope 

of managing those resources sustainably.   A prolonged demographic 

transition could lead to a collapse/depletion of natural resources.  In 

that situation the population would be growing at a great rate and using 

an ever increasing amount of natural resources.  A population undergoing 

a demographic transition has very little, if any, hope of managing its 

resources sustainably in the short term.  

     Included directly above is a graph showing the demographic 

transition for the continent of Africa.  On the whole the graph shows a 

wide gap between the crude birth and death rates.  This is an indicator 

of rapid population growth for the continent.  The graph is included to 

show a region undergoing the population transition.  Any country, 

continent, or geographical region at a similar point in the demographic 

transition would not be in a position favorable to the proposed building 

materials transition.  The population growth pressure would put great 

pressure on building material resources.  People would be looking to 

obtain whatever building materials they could, as cheaply as they could.  

This could potentially slow or even halt a transition towards sustainable 

building materials.



Forestry Transition

     The forestry transition is similar to the demographic transition.  

At its outset a large percentage of a region is covered with forest.  

During the transition rapid deforestation occurs.  At the end of the 

transition forest cover stabilizes at a level lower than was previously 

the case.(Drake, 1993)  The graph below shows an increasing gap between 

the total forest cover and the extent of the natural forest cover.  The 

gap shows that the extent of natural forest cover as a portion of the 

total forest cover is decreasing.  This is significant for two reasons.  

The first is that the United States is continuing to use up its old 

growth forests.  The  second significance of this graph is that there is 

an attempt being made to replace wood harvested, although the decline of 

total forest cover is evidence that this replacement is not on a one for 

one basis.
Total Forest vs. Natural Forest Extent in the United States
      With respect to the proposed building materials transition, the 

forestry transition has several implications.  First is the eventual 

necessity of using faster growing, smaller diameter trees form second and 

third growth forests.  This shift occurs either because of the total 

depletion of old growth forests or it  occurs as a result of conservation 

efforts.  As noted earlier in this text this shift towards the use of 

smaller, faster growing trees is occurring in the United States.  This is 

evidenced by increases in the use of glue laminated lumber, LVL, and 

engineered wood I-joists.


Roundwood Production--industrial
      The graph above clearly shows the link between increased population 

and increased demand for roundwood.  A shift towards utilization of 

smaller, faster growth tree species could aid in meeting this demand 

while slowing or reversing total forest area depletion.  This can be an 

important factor with respect to the environment as a whole.  As forest 

land is depleted, there is more soil erosion.  This erosion can lead to 

ground water contamination and the reduction of arable land.  Both of 

these factors directly affect the lives of the population in terms of 

drinkable water and the amount of food produced.  This can put the 

population (human, plant and animal) at risk.

     What bearing does this have on other countries?  Certainly any 

country at the start of, or midst of, a sustainable building materials 

transition should look to information about their forestry assets and 

practices.  If large numbers of old growth trees exist the price of 

products made from these old trees may be smaller than the prices of 

sustainable materials.  In turn, this could slow or halt a transition 

towards sustainable building materials.  Attention must also be paid as 

to what is being done to replace the trees harvested.  Are the species 

being planted the same as the ones that are harvested?  Perhaps faster 

growing trees are being planted.  If the latter is the case it must be 

made clear that the same building materials are not obtained from the two 

different types of trees.  There is a reduction in size and quality of 

materials that can be obtained.



Urbanization Transition

     As with the above transitions, the urbanization is characterized at 

the outset by a large rural population and a small urban population.  

This transition is driven by two factors.  The first is the rural to 

urban migration of the population.  The second is the growth of the 

existing urban population.(Drake, 1993)
Rural vs. Urban Population in the United States
 In the later stages of the transition urban population growth declines 

and potentially reverses itself.

     The above graph shows that the United States is in a period 

following an urbanization transition.  Urban population growth may be 

slowing.  With the rapid growth of the suburbs, some may argue that the 

trend is reversing.

     The graph below shows the beginnings of an urbanization transition 

in Africa.  Currently the urban population is increasing at a rate that 

is beginning to surpass the rural growth rate.  Again it should be 

brought to the readers attention that all post 1995 data in the graphs is 

projected data.  From this projected data it appears that the rural and 

urban populations of Africa will reach the turning point somewhere near 

the year 2020.
Rural vs. Urban Population in Africa.
     Again, what does this information mean in terms of the proposed 

building materials transition?  As with the demographic transition there 

are obvious connections between the number of people and the number of 

dwelling units.  This, as before, impacts the natural resources of the 

region.  However, the urban transition is likely to lead to higher 

population densities.  The graph below clearly represents the occurrence 

of this trend in the United States.  Higher densities also usually lead 

to different building materials.  These are traditionally nonrenewable 

materials.  The significance of this is that there is some savings in the 

amount of materials used for construction in high density construction 

although those materials may be nonrenewable.  Higher density 

construction means a potentially smaller total exterior building surface 

area.  This not only saves materials, and thus natural resources in the 

form of building materials, but also allows for a savings in energy usage.

     

Population Density in the United States
Policy Implications

     There are several policy implications fostered by a proposed 

transition of building materials.  First, forest management policies will 

be impacted.  As evidenced in the graph entitled "Total Forest vs. 

Natural Forest Extent in the United States" which appears in the Forestry 

Transition section of this text, the amount of total forest cover in the 

United States is decreasing.  Steps must be taken to halt this reduction 

of forest cover or a transition to sustainable building materials may not 

be possible.  Great care must be used in halting this forest cover 

reduction.  Sandra Postel and John C. Ryan point out that, "When diverse 

populations of trees are replaced with genetically uniform stands, future 

timber harvests are put at risk."(Postel & Ryan, 1991)  Efforts must be 

made to maintain biodiversity.

     Secondly waste disposal policies must be changed.  The cost of 

disposing of materials in a landfill should carry some weight in the 

decision of discard materials.  An example of this is the formal plan to 

recycle wastes during the construction of the $262 million Portland 

Trailblazers' Arena project in Portland, Oregon.  All contractors' bid 

specifications included a section on waste management.  With 62% of 

construction complete, nearly 97% of construction debris was sent to 

recyclers.  This saved and estimated $141,000 in landfill dumping 

fees.(Building Design and Construction, 1995)  The fact that this 

recycling program was prompted by high dumping fees shows that this type 

of policy change can be an effective way of channeling ecological costs 

into economic costs.

     Lastly, the general public and governmental bodies must be made 

aware of the ramifications of their choices of building materials and 

policies.  While this may be difficult, it is a worthwhile endeavor.  One 

need only look at the spiraling national debt of the federal government 

of the United States to see the consequences of ignoring future costs.  

That government is facing substantial cuts in its programs of elderly 

health insurance and student financial aid.  The short sighted approach 

to policy can clearly have drastic, long term repercussions.



Recommendations
1)  A transition towards sustainable building materials/methods should be 

encouraged.  This could be the encouraged use of potentially renewable 

materials such as wood.  It could also take the form of adaptive reuse of 

structures.  In addition, it could also take the form of reuse of 

specific, nonrenewable building components.  Certainly this should become 

a part of the education of every designer and builder.
2)  As the earlier discussion of Life-Cycle Assessment suggested, the 

early merging of ecological and economic costs should be studied and 

striven for.  This has been described by others as a series of phases:


        Phase 2:        Environmental pollution as a cost factor
                        Polluters begin to see that it may be beneficial to reduce pollution
                        levels (adaptations at process level).

        Phase 3:        The environment as a boundary condition
                        Polluters incorporate the environmental factors when planning new
                        investments, and are thereby forced to produce or consume
                        differently (adaptations at process and product levels).

        Phase 4:        The environment as a policy-determining factor
                        The environment factor plays a role for polluters when optimizing
                        their activities, and this leads to different system designs (adaptation
                        at system level).

        Phase 5:        The environment as an objective
                        Society incorporates the environment as a logical factor and goal in
                        social and economic policy.  As a result of this, there will be
                        changes in the pattern of production and consumption as well as in
                        the mental attitudes (adaptations at structural level){Dutch Committee for Long-
                        Term Environmental Policy}
 

Currently the United States is in Phase 2.  The example of the Portland
Trailblazers project clearly demonstrates that environmental pollution is
beginning to be seen as having a cost.  This train of thought leads
directly to the next recommendation.

3)  The cost of dumping materials in landfills should be raised to a
level which encourages builders to minimize the amount of materials they
dump.  Certainly this should go hand in hand with an increased recycling
effort to re-use those items that are, at present, thrown away on a
construction site.

4)  The widespread use of sustainable materials should be encouraged
through governmental actions.  This could take the form of building
design standards that specify the amount of nonrenewable materials that
can be used in a building.  Several states already mandate the maximum
amount of energy a building can use during one year.  Similar thinking
and legislation could apply to nonrenewable building materials.

5)  An effort should be made so that all people, from the business
executive to the factory worker, are aware of how their decisions about
building materials affect the environment.  This may sound like grand,
abstract thinking.  However, each of us spends countless hours of our
lives in buildings of one sort or another.  Our use of these structures
implies a responsibility for these structures: for their design, use and
eventual demolition, recycling, or reuse.  We all make decisions
regarding our responsibility, whether it be to take an active role in the
decision making process or to ignore the decision making process
entirely.  Those decisions are of vital importance to the continued
existence of humankind on the spaceship Earth.
 
 
 

NOTES
1. All dollar amounts are in U.S. dollars.
2.  Common designation 2x4.
3.  It is important to note the difference between nominal and actual
dimensions.  For example; a 2x4 has actual dimensions of 1.5x3.5.
 
 
 
 

REFERENCES
1.Kurt Brandle, The Systems Approach to Sustainability in Building, paper
presented to the Architectural Institute of Korea, 4/29/95.
2.William D. Drake, Population-Environment Dynamics, chapter XIV Towards
Building a Theory of Population-Environment Dynamics: A Family of
Transitions, copyright 1993, University of Michigan Press.
3.Dutch Committee for Long-Term Environmental Policy (editor),The
Environment: Towards A Sustainable Future,  copyright 1994, published by
Kulwer Academic Publishers.
4.Robert Johnson, The Economics of Building,  copyright 1990., published
by John Wiley & Sons, INC.
5.Steve Loken, Rod Miner, Tracy Mumma, Guide to Resource Efficient
Building Elements 4th. ed., copyright 1994, published by the Center for
Resourceful Building Technology.
6.Sandra Postel and John C. Ryan, State of the World 1991, Chapter 5
Reforming Forestry, copyright 1991 Worldwatch Institute, published by
W.W. Norton and Company.
7.Alex Wilson, P/A  April 1995, How Green is Your Building? .
8.Gordon Wright, Building Design and Construction, February 1994,
Ecology and Economy Boost Use of Engineered Wood.
9.Building Design and Construction, February 1995, Arena's waste
recycling plan pays dividends.
ELECTRONIC REFERENCES
 10.  Rainforest Action Network, Rainforest Action Network Home Page,
World Wide Web.