as development density, proximity to public
transportation, no irrigation systems, use of locally
important to note, because they directly influence
manufactured materials, low-VOC adhesives, low-
the percentage-based calculations of LEED cost
emission carpets) that earn 1 point each. At the
impacts. For example, LEED-based measures that
other extreme, the study illustrates that some credits
had similar total costs in the two projects (e.g.,
(renewable energy, for example) can cost hundreds
water-efficient plumbing fixtures, carbon dioxide
of thousands of dollars each--and still earn 1 point.
sensors) have significantly different impacts as a
The selection of credits used to achieve a LEED
percentage of the total project costs. It is therefore
rating can therefore result in a wide range of
important to consider both the $/GSF and
overall LEED costs.
2. A range of different strategies can often be
used to earn the same individual LEED credit.
6. Costs Based on LEED Version 2.1
Many of the LEED credit criteria are performance
All credit cost assumptions are based on LEED
based rather than prescriptive. This allows design
Version 2.1, which was the current rating system at
teams flexibility in defining an approach to credit
the time of the study. As LEED is a constantly
compliance. Different strategies can also result in
evolving program, new versions are expected in the
significantly different cost impacts. An example
near future (versions 2.2 and 3.0 are already in
from the cost study is credit SS-6.1, Stormwater
progress, with projected release dates in 2005 and
Management (Rate and Quantity), used in the
2006, respectively). While the specific changes to
Courthouse model. In the "low cost" scenarios, the
LEED are unknown at the time of this report, it is
credit was earned by increasing the amount of site
expected that the new versions will warrant
plantings and reducing the amount of site paving.
adjustments to the cost impacts derived in the
This approach actually reduced construction costs.
In one of the "high cost" Gold rating scenarios, a
vegetated roof system was installed as an alternative
Because of these varying cost estimate qualifiers,
approach. The premium for the vegetated roof
system was approximately 0,000. While the
of the study cannot be considered reliable for
vegetated roof has additional benefits and was used
projects of significantly different scope or scale.
to earn an additional LEED credit (SS-7.2, Heat
However, the detailed cost breakdowns included in
Island Reduction), it still represented a significantly
the study can provide a basis for other projects to
more expensive approach to credit compliance.
evaluate LEED costs. The "apples to apples"
comparisons of the Individual Credit Reviews and
3. The cost of some credits varies significantly
Cost Estimates (Section 2 and Appendices C and
based on the building type and building
D) can serve as a starting point in understanding
program. For example, in the Office Building
the typical scope and potential cost implications of
model, earning credit MR-7 (Certified Wood)
various LEED measures. Additionally, the soft cost
involved a moderate cost premium (approximately
summaries and breakdowns included in Section 4
,000) because wood use in the building was
and Appendices G and H can provide a basis for
limited (some doors and a small amount of
understanding the extent and costs of LEED-
casework). In the Courthouse model, on the other
related professional services.
hand, the cost premium to earn the credit was
almost 0,000. The Courthouse has extensive
Addressing LEED Cost Variables
wood finishes, including paneling, doors, casework,
and fixed furnishings in the courtrooms and judges'
The study indicates that there is an inherent degree
of variability to LEED construction cost impacts.
4. Some credit costs vary based on region-
The primary factors creating this variability include
specific or project-specific issues. Two examples
illustrate this point. In some parts of the country,
1. There is no correlation between the point
earning and exceeding the requirements of credits
value of a LEED credit and its cost. There are
MR-5.1/5.2 (Local/Regional Materials) can be
many "no cost" and "low cost" LEED credits (such
easily accomplished at no cost. In other locations, a
GSA LEED COST STUDY