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METHODOLOGY
GREENING EAST CAMPUS
MIT
“What gets measured gets managed.�
                    Sir John Browne, Chief Executive Officer, British Petroleum, 1997

Financial costs and benefits of buildings are generally well understood and
effective quantitative methods are available to assess building expenditures
and investments.  However, many architectural decisions have effects far
deeper than the easily recognized factors of cost, function, and aesthetics. Even
though such a statement may be widely agreed upon, designers and other
decision makers currently lack the frameworks necessary to consider the
broader implications of their decisions, such as the sustainability issues of
building occupant wellness, production and construction worker safety, and
environmental impact.  Traditional economic cost-benefit analysis cannot fully
embody the sustainability vector of a decision, as many of the health and
environmental components are difficult, if not impossible, to value monetarily, let
alone discount in today’s market context.  In this section, a tool is presented
that aids decision-making around the non-monetary attributes of a sustainable
building system.  Case study analyses of the East Campus Project at the
Massachusetts Institute of Technology using this framework are presented as
follows:

Conceptual Framework

The most comprehensive evaluation of non-monetary impacts of a construction
project starts by viewing the project as a process occurring from “cradle to
grave:â€�  construction, use, demolition, and reuse.  Each life cycle stage
consumes resources, releases wastes to the environment, and produces
benefits and services for users.  Inputs include building materials, labor,
energy, and maintenance supplies over the lifetime of the building as well as
many others  too numerous to list exhaustively.  Wastes include construction
waste, used consumable supplies for building operation, emissions from
energy production used to heat and light the building, and other residuals of
construction and use.  Identification of benefits is a subjective exercise that
largely depends on functionality of a built structure, but some basic benefits
include shelter, specialized work facilities, social interaction, and cultural
qualities.

Various design features can affect the types and amounts of inputs required,
wastes produced, and benefits gained.  However, these features do not act
alone, and their effects are not simply additive.  The performance of each
depends on its interaction with the rest of the building’s design and its
surrounding environment.  Figure 1 demonstrates this dynamic.  The goal of
sustainability entails minimizing the inputs to and outputs from the life cycle of a
building (or product or service).  This can be achieved without sacrificing
benefits and, in many cases, can contribute to them.  However, given the varying
natures of the different inputs and outputs, as well as the complex interaction of
various design features, it is difficult for designers and project managers to
determine how best to meet the goal of sustainability within the constraints of
sites, budgets and engineering realities.

Such difficulty arises from the fact that sustainability issues are based on
various levels of scale, affecting varied physical and social phenomena.  While
most of these effects can be measured with one or another set of units,
converting these measures into a common unit (either money or some sort of
composite index) in order to sum them along a common dimension, involves
subjective valuation of the relative importance of each issue or phenomenon.  Is
reduction of CO2 emissions more significant than reduction of dioxin releases
or improving stormwater retention?  Answers to this question depend on
whether global warming, toxins in the environment, or water resources and
flood control are the serious problem and for whom the impacts are to be
accrued.  Our present level of understanding of the world allows us to make
subjective judgements on these questions, but does not allow us to answer
them using objective and defensible technical methods.  Therefore, these types
of composite analyses, by definition, involve subjective evaluation, which is
generally presented in varying degrees of transparency.

Today in the United States, the most widely known tool for improving the
environmental performance of a building is the Leadership in Energy and
Environmental Design (LEED) green building rating system, developed by the U.
S. Green Building Council.  LEED provides a “shopping listâ€� of design
and engineering options to improve the environmental performance of a
building or site along with a certification system to reward compliant buildings.  
This system essentially gives equal weight to most environmental benefits and
produces a composite “score� for the sum of all measured sustainability
criteria.  It does not provide for the weighting of various impacts based on
personal judgment, nor does it include an underlying framework to
comparatively assess design options.

Current methods to assess alternative design scenarios and design tradeoffs
primarily consist of first-cost minimization and increasingly include Life Cycle
Cost Assessment (LCCA), where operating costs are estimated to determine
payback periods for initial investments in improvements such as energy efficient
equipment.  Research is well underway in Europe and has a strong foothold in
the U.S. to make use of Environmental Life Cycle Assessment (LCA) and to
incorporate LCCA into the LCA methodology .  Overall, today’s most widely
practiced methods for making sustainable building decisions consist of LEEDâ
€™s point system and some type of cost analysis.  A methodological framework
to assess non-monetary impacts and multi-purpose design decisions is
lacking.
Comprehensive Decision Making and Life Cycle Assessment