105-D. Global Green Cost Analysis.pdf
Attachment D
City of Cupertino
Green Building Ordinance Cost Analysis
Prepared by:
Global Green USA
March 21, 2011
Background
At the request of the City of Cupertino Community Development Department, Global
Green prepared the following analysis of how the proposed Green Building Ordinance
requirements would impact development costs of projects in the City.
The purpose of the green building ordinance is to reduce resource use, create healthier
living and working environments, reduce greenhouse gas emissions, and foster a
consistent regulatory approach between the City of Cupertino and other public agencies
in Santa Clara County. The proposed ordinance augments existing City planning and
building codes (including the State of California Cal Green code that went into effect on
January 1, 2011) by requiring that new development projects, tenant improvements, and
substantial additions comply with additional criteria in design and construction, up to and
includingformal certification per the LEED Rating system, or (for residential projects),
the Green Point Rated program.
Global Green conducted an analysis of three development projects, representative of the
building type, size, design, and construction methods typical in the City of Cupertino, that
were approved by the City within the past five years. The objective was to generate a
rough estimate of the additional costs that would be incurred as a result of meeting the
Green Building Ordinance standards, and todetermine if any significant alterations to
the design of the proposed projects would be required.
These projects are as follows:
10750 Johnson Avenue –anew 2,380 sq.ft. two-story single-family dwelling
10845 North Stelling Road –20new two-story townhousestotaling 32,200 sq.ft.
10900 North Tantau Avenue –anew two-story 96,680 sq.ft. shell office building
Methodology
Global Green received the building plans for each project that were used for the planning
approval. The plans provided basic project information regarding size, number of
dwelling unity, height, location of parking, and general landscaping, but did not provide
detailed information on specific building systems, construction materials, or plant
selections. Therefore the analysis was conducted at a high level, with a focus on the
prerequisites. Theobjective of the review was to:
Determine if any aspect of the current design created a significant barrier to
achieving LEED certification.
Assess what, if any, modifications would be needed to earn LEED certification.
Develop a rough estimate of additional costs that would be incurred by the green
building ordinance.
The LEED rating system was the basisfor the analysis,as it is the most stringent of the
rating systems referenced in theproposed green building ordinance. The current
versions of the LEED Rating Systems for Building Design and Construction (3.0) and
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Homes (2008)were used.To earn certification, a non-residential project must meet
seven prerequisites and earn at least 40 points. Residential project must meet19
prerequisites and earn at least 50 points
The green building rating systems referenced in the Cupertino ordinance, US Green
Building Council’s Leadership in Energy and Environmental Design (LEED) or Build it
Green’sGreen Point Rated (GPR), are performance based, which allows flexibility in the
type of green building measures being proposed. This leads to different choices
regarding credit selection and the costs associated with achieving those credits.
Furthermore, some green building measures can lower costs, such as the reduction in
the size of the heating and cooling system due to better insulation, building orientation,
and passive cooling and heating improvements.
Also taking into the consideration were the mandatory provisions of the California
Building Code requirements that went into effect on January 1, 2011, most notably the
Cal Green code,which has prescriptive requirements for water efficiency, building
material emissions, and a number of construction practices. When these code-required
items overlapped with LEED prerequisites or credits, no additional costs were assumed
to be incurred as a result of the Green Building Ordinance.
Findings
Analysis of Current Design
The current designs of the projectsdo not create any significant barriers to achieving
LEED certification. The prerequisites that are not currently met in the areas of energy
efficiency and ventilation can be addressed through upgrades to the existing building
design, but would not require major modifications to the designs. As LEED is a
performance-based system the design teams can select credits that appropriate to the
design and budget of the projects. For example one project could decide to emphasize
energy performance while another could choose water-related strategies and third could
focus on credits related building materials. As there are many options it is not expected
that any of the projects will have difficulty in identifying a sufficient number of credits to
earn certification.
Modifications Required to EarnLEED Certification
The modifications that would be required can be achieved within the current designs.
Most significant is the need to fulfill the requirements related to the energy performance
and ventilation prerequisites.
LEED projects arerequired to improve energy performance to 15% better than the 2008
California Title 24 (Part 6) code. Based on the energy code analyses submitted to the
City, 10750 Johnson Avenue is currently exceeding Title 24 by 18.5, thusmeeting the
15% improvement thresholdprerequisite.10845 North Stelling Roadis currently
exceeding Title 24 by approximately 8% and 10900 North Tantau Avenue is currently
meeting the mandatory code minimum. These two projects would requirethe
specification of amore energy efficient building envelope features andmechanical
systems in order to comply with the LEED energy prerequisite.
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To achieve sufficient points to earn certification, all three projects would also need to
incorporate the following:
Upgraded mechanical system design in order to verify that LEED Indoor
Environmental Quality prerequisites are met and specifying mechanical equipment
refrigerants that are free of HCFCs.
Modification of the landscape plans to further reduce water use.
Specification of environmentally preferable building products, including recycled-
content, low-emissions, and locally manufactured materials.
Stormwater management systems to capture and/or treat stormwater before it leaves
the site.
Increased requirements,from the current City standard of 50% to 75% rate of
diversion,for construction and demolition waste.
In construction, all threeprojects would need to include additional construction
verification measures. For 10900 North Tantau Avenue thiswould include additional
commissioning, monitoring and verification of energy performance. For the 10750
Johnson Avenueand10845 North Stelling Roadprojects, the additional required
measures are the HERS (Home Energy Rating System) verifications that are includedin
the LEEDenergy prerequisite: Quality Insulation Installation, Duct Leakage, and
Refrigerant Charge.
Estimate of Additional Costsand Savings
Generally green building has been determined to result in an average additional
construction cost of 2%. Workshops conducted in the fall by the Building Standards
Commission in regard to the recently adopted Cal Green code estimated that the costs
associated with the Cal Green requirements areapproximately $0.50 to $1.00 a foot.In
addition, a study recently completed by Global Green for the City of Mountain View
Energy Reach Code identified an average additionalcost of $.40per sq ft. for residential
and$1.50 for non-residential buildings to incorporate the energy efficiency upgrades
needed to achieve 15% improved performance.Combined, these costs are $.90 to
$1.40 per sq. ft.for residential and $2.00 to $2.50 per square foot for non-residential.
Compliance with LEED or GPR also results in costs for registration, certification,
additional design team coordination, and documentation during construction.
A summary of the estimated costs of the upgrades for the three study projects is
provided in Table 1.The costs are based on: a) theassumptions for the incremental
cost of the energy system upgrades environmentally preferable materialsdescribed
above, b) registration and certifications fees, c) field verification fees, and d) an estimate
for preparing and submitting certification documentation to the US Green Building
Council/Green Building Certification Institute.
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Table 1: Incremental Costs of Upgrades to Achieve LEED Certification
10750 Johnson 10845 North 10900 North Tantau
Ave.Stelling RoadAvenue
Single-Family Multi-Family Non-Residential
ResidentialResidential
2,380 sq.ft.32,200 sq.ft.96,680 sq.ft.
1
Registration$450$900$900
1
Design$2,500$4,000$10,000
2
Energy Systems$952$12,880$145,020
3
Materials$1,785$24,000$72,510
Construction $1,000$10,000 $25,000
4
Verification
(HERS)(HERS)(Commissioning,
M&V)
5
Documentation$2,500$7,500$25,000
Preparation
Certification/Provider
$1,500$3,500$2,250
6
Fee
Total Incremental $10,687$62,780$280,680
Cost
7
Cost/Sq.Ft.
$4.49$1.94$2.90
Percent Cost
2.2%1.0%1.5%
Increase
1.From USGBC web site
2.Assumes 25,40 and 100 hours at an average cost of $100/hr.
3.Based on Mountain View Energy Reach Code Cost-Effectiveness Study:
$0.40/sf average for residentialand $1.50/sf for non-res,
4.Assumes average incremental cost of $0.75/sq.ft.
5.Based on typical costs for current Global Green projects
6.Davis Energy Group LEED for Homes fee schedule, GBCI fee schedule
7.Assumes $200 per square foot average cost of construction
Based on results for similar project types in Mountain View Energy Reach Code Cost-
Effectiveness Study, the estimated annual energy savingsis $115/year for the single-
family house, $1,600 for the multi-family, and $18,000 for the non-residential building.
Additional savings would result from reduced water use and lower maintenance costs.
The projects may also experience more rapid appreciation or higher assessed value at
time of sale.
Summary
It is feasible for all three projects to achieve LEED or GPR certification without requiring
significant design modifications. The primary source of increased construction costs is
from upgrades to the heating, cooling, and hot water systems. Other costs include those
related to LEED or GRP registration and certification, green rater and HERS rater fees,
and additional design fees from the project architects and mechanical engineers.
Combined, the estimated incremental cost increases are consistent with incremental
cost studies such as the Cost of Green Building Revisited (Davis Langdon, 2007) that
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determine that the incremental cost of achieving LEED Certification range from 0% to
5% of total construction costs, with most projects experiencing 3% or less of an increase
in costs.
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Global Green USA –Green Building OrdinanceCost Analysis