Page 158 - Green Building Through Integrated Design

134 COSTS OF GREEN BUILDINGS

that there is no right answer to the question: “how much does a green building cost?” I
often tell audiences that the definitive answer to this question is simple—it depends!
Overall, costs associated with green design and construction may exceed 1 percent
of construction costs for large buildings and 5 percent of costs for small buildings,
depending on the measures employed.
Higher levels of sustainable building (for example, LEED Silver, Gold, or Platinum
standard) may involve some additional capital costs, based on case studies of com-
pleted buildings in the U.S. LEED projects also incur additional soft (nonconstruction)
costs for additional design, analysis, engineering, energy modeling, building commis-
sioning, and certification. For some projects, additional professional services, for
example—including energy modeling, building commissioning, additional design
services, and the documentation process—can add 0.5 to 1.5 percent to a project’s
cost, depending on its size.

Green Building Cost Studies

Given the high level of interest in the costs of green, it’s surprising that there are so
few rigorous studies of the cost of “green versus nongreen,” for similar projects. Here
are a few of the studies that point the way toward a better understanding of green
building costs.

THE 2003 CALIFORNIA STUDY

A 2003 study for the State of California was the first rigorous assessment of the costs
and benefits of green buildings.* Drawing on cost data from 33 green building projects
nationwide, the report concluded that LEED certifications add an average of 1.84 percent
to the construction cost of a project. For Gold-certified office projects, construction cost
premiums ranged from 2 to 5 percent over the cost of a conventional building at the
same site.

THE 2004 GSA COST STUDY
A 2004 study for the General Services Administration of the costs of achieving vari-
ous levels of LEED certification for government buildings looked at both new con-
struction and remodeling projects. It supports somewhat similar conclusions to the
work for the State of California. For example, in the California analysis, a $40 million
public building seeking a LEED Gold level might expect to budget about 2 percent, or
$800,000, extra to achieve this certification.
The 2004 study carefully detailed two typical projects, a new federal courthouse
(with 262,000 square feet and a construction cost of $220 per gross square foot) and

*Gregory Kats et al., The Costs and Financial Benefits of Green Buildings, 2003, available at www.cap-e.com/
ewebeditpro/items/O59F3303.ppt#1, accessed March 6, 2007.