As we showed earlier, a main barrier to implementing green buildings has
been the perceived cost increases for green measures. It is true that many
of the earlier green projects in the 2000 to 2005 period were more costly.
This is largely because the transition to new methods of design and construction
involves a lot of social learning that is accompanied by construction
mistakes, poor designs, unproven new products and a myriad of reasons
leading to extra costs. By 2005 and especially in 2006, however,many
design and construction teams had done enough green projects to start
lowering costs tomore conventional levels.
In 2006 the developer of a large LEEDPlatinumproject in Portland—
a very complex, 412,000-square-foot, mixed-use medical facility — reported
a cost premium (net of local, state and federal incentives) of about
1%on a $145million project.30 Now, this developer had designed and built
30 prior LEED projects and used a very experienced architect and engineering
team, already well-versed in green building methods. But their
success does point to the fact that future green buildings can be built without
any initial cost premium, once design and construction teams garner
enough experience.
What determines the cost of a green building?
• First and foremost, it depends on what the design teamand owner are
trying to achieve. If it’s a LEED Platinum building, they most likely
will use green roofs and photovoltaics, two expensive additions to a
project that may not be included in a LEED Silver or possibly even a
LEED Gold project.
• Second, it depends how early in the process the project decides to pursue
sustainable design and construction.As we show in the section on
integrated design, it’s best if that decision is made as early as possible,
even during the site selection process, so that a building can be properly
oriented, with a rectangular shape that allows for good daylighting
and e‹cient passive solar designmeasures.
• Third, it depends still on the experience of the design and construction
team with green buildings; the more experience, the less the cost
premium based on both fear of the unknown and lack of knowledge
about sourcing green products, for example. Less-experienced teams
often use green building consultants to help them out with their Šrst
project, to accelerate the learning curve.
Integrated design often leads to creative solutions that allow teams to
“tunnel through the cost barrier” and design a more energy-e‹cient
building at a lower initial cost.31 Typically, this is done by having the architecture
do some of the work of cutting energy use, as well as heating and
cooling a building with daylighting, shading devices, highly e‹cient windows,
orientation and heavy mass construction. Green buildings can also
cut other project costs by saving on infrastructure investments and connection
charges for storm drainage and sewage connections through total
water system management. Often, by thinking strategically in the Šrst 30
days of a project, you can inšuence 65% of total costs by assessing a
broader range of options,making choices among key cost drivers and having
a clear vision of results. This puts a premiumon thinking (vs. doing), a
concept thatmany Americansmay Šnd challenging.
One of the most widely cited studies of the costs of green buildings
was done by the international cost-consulting ŠrmDavis Langdon in 2004
and updated early in 2007. Using their own proprietary database of actual
building costs, and comparing 45 LEED projects with 93 other non-LEED
projects, Davis Langdon discovered that green building costs (for three
types of common projects—libraries, academic classrooms and laboratories)
were statistically no diªerent than conventional building costs when
normalized for year of completion (taking cost inšation out of the analysis)
and location (rešecting the variation of building costs by locality).
Their work showed that themajor cost driver is the building program, that
is, what the building is designed to achieve. A simple branch library in the
suburbs might be fairly cheap to construct, but a downtown main library
will likely bemuchmore costly, on a dollars-per-square-foot basis.You can
Šnd a large big-city downtown library by a name architect that costs $500
per square foot, as well as one that serves the same function and costs only
$230 per square foot.
The Šgure below shows the results of the most recent Davis Langdon
study for ambulatory care facilities (one of Šve categories with enough
data from which to draw Šrm conclusions).32 The 2007 update included
additional project types and more cost data, all standardized to Sacramento,
California,mid-2006 costs. The conclusions of the study were unchanged:
certiŠed green buildings don’t cost any more than conventional
buildings, on a per-square-foot basis. What matters most: the building’s
design objectives.
Jerry Yudelson, Green Building A to Z, New Society Publisher
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