Human Settlements Review - Parliamentary Monitoring Group

ABSTRACT
Human Settlements Review, Volume 1, Number 1, 2010
A Sustainable Housing Calculator: Demonstrating
the long term benefits of sustainable building
interventions
Johan Burger, Mark Swilling and Jerome Lengkeek
School of Public Management and Planning
University of Stellenbosch University
“While the environmental and human health benefits of green building have been widely
recognized, [research reveals that] minimal increases in upfront costs of 0-2% to support
green design will result in life cycle savings of 20% of total construction costs – more than
ten times the initial investment. In other words, an initial upfront investment of up to $100,000
to incorporate green building features into a $5 million project would result in a savings of $1
million in today’s dollars over the life of the building.” Aileen Adams commenting on “The Costs
and Financial Benefits of Green Buildings,” a report to California’s Sustainable Building Task
Force, October 2003.
Introduction
The preconceived notion that sustainable
building interventions are too expensive to be
considered for possible use in subsidy housing
developments has been challenged for many
years. During the past decade, the cost of
many of these interventions has been falling
rapidly, and the need for a reduction in water
and electricity use has become more acute.
The result of this intersection between the
questioning of old assumptions, falling costs,
and growing environmental concerns has
been the increased use of sustainable building
interventions, particularly in the commercial/
industrial and high income residential sectors.
However, there has been little uptake of these
interventions in the low income, mixed income
and subsidised housing sectors. There is
therefore a pressing need for tools that can
enable government officials, developers, and
housing contractors to measure the viability
of more sustainable methods of construction,
particularly in these lower income sectors.
A significant step in this process was taken
with the life cycle assessment case study that
was previously published in the first edition
of the Sustainability Institute’s “Sustainable
Neighbourhood Design Manual” (SI, 2009).
It demonstrated that even a development
that included a full range of sustainable
interventions would be cost effective when
measured over a 30-year life cycle. By its very
nature of being a case study, its findings were
directionally very important, albeit somewhat
limited due to the use of data from a particularly
expensive case.
The next natural step in the process of defining
financial viability in settlements was to find
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