Much can be learned about the commissioning of green buildings from a study assigned by the Colorado Governor’s Office of Energy Management and Conservation. The study provides a wealth of information to help guide owners in setting commissioning budgets for LEED-NC projects as well as understanding the benefits and potential pitfalls related to commissioning and commissioning of LEED pro...
Much can be learned about the commissioning of green buildings from a study assigned by the Colorado Governor’s Office of Energy Management and Conservation. The study provides a wealth of information to help guide owners in setting commissioning budgets for LEED-NC projects as well as understanding the benefits and potential pitfalls related to commissioning and commissioning of LEED projects. It presents a scope of commissioning services and associated costs and well as owner’s feedback on the LEED and commissioning processes. The study included large and small buildings as well as owners with varying levels of experience with incorporating commissioning into the design and construction process. The study was conducted and information was gathered through detailed design team and owner interviews.
Is LEED cost-effective? This question comes up time and time again as building owners and design teams who want to build the best building possible are considering the option of pursuing LEED-NC certification. This paper presents the results to address this question with a focus on commissioning.
Also included is an expanded discussion of the cost and benefits of the commissioning of these projects. This effort included the convening of an advisory committee, a survey of owners of LEED-NC certified buildings in Colorado and publication of a white paper entitled “The Costs and Benefits of LEED-NC in Colorado.” The process was structured to gather hard (construction-related) costs and benefits in a manner as consistent as possible, while still capturing the occupant impressions and other soft (non-construction-related) costs and benefits. Research has shown that high performance, energy-efficient buildings provide a variety of benefits including improved learning, occupant health and satisfaction, and lower energy and water costs. There are a growing number of studies addressing the cost and benefits of building green and commissioning green buildings in various parts of the nation; Colorado has historically lacked such a resource. This research project begins to address these issues as well as explore strategies to help project teams create more cost-effective, high performance green buildings.
| The new recreation center in Boulder, Colo., one of the projects evaluated in a 2006 study of green projects by Rebuild Colorado, displays a sign announcing its certification as a LEED-accredited building.
Photography: (c)2007 City of Boulder Parks & Recreation Dept.
Thankfully, LEED-NC requires commissioning. After all, commissioning, like LEED, is focused on sustainability. Commissioning is intended not only to deliver building systems that work, but also to set the stage for ongoing, sustained operational success of these systems. Commissioning is one of the most cost-effective means of reducing operating costs and improving energy-efficiency and occupant comfort in commercial buildings.
Is LEED-NC cost-effective in Colorado? What does it cost to build a high-performance green building? What is the cost-premium for a LEED-NC certified building? How much should I budget for a LEED-NC building and commissioning of a LEED-NC building?
These questions come up time and time again as building owners and design teams who want to build the best building possible are considering the option of pursuing LEED-NC certification and high performance green building. This project attempted to address these questions as well as begin to address the following:
• Of the four LEED-NC certification levels available, do certain levels cost more than others to obtain?
• What are the factors that make some LEED-NC projects cost less than others?
• Why do some projects cost so much more, and how could costs be better managed in the future?
This research is only one step in an ongoing endeavor that has the potential to more effectively use funding for design and construction of buildings, to help produce better buildings at every stage of a building’s life, and to change perception and encourage innovation in design, construction and operation of buildings.
Builders often claim that building green or to the LEED criteria is too expensive and that they can’t afford to incorporate high-performance or green features into construction. What is often left out of the discussion is the basis for this claim. For example, costs more compared to what? Compared to a similar building down the street; compared to the last building that was built; compared to the original budget, which may or may not have been based on the current goals of the project or market conditions; or compared to a code or jurisdictionally compliant building? Design and construction are complex, as are the factors and forces that influence cost. By evaluating multiple buildings under this report we are able to share differing experiences and approaches taken by teams in construction of LEED buildings.
This study attempted to quantify the costs and benefits associated with achieving LEED-NC certification with the baseline or preexisting standard being if the building were not constructed to LEED-NC. Some project teams incorporate certain requirements of LEED, such as commissioning or energy modeling, as business as usual and do not consider them additional costs. Therefore, the relative cost premiums in this study are exaggerated for such project teams. To take it a step further, if a project team or owner considers their building design and construction standard and equal to LEED, then in reality there would be no premium.
Summary of findings
Table 1 (p. 42) summarizes the survey findings. The survey was limited in scope, but the sampling is significant enough to support the key conclusions.
Based on the discussions with the design teams and the data collected for these LEED-NC version 2.1 certified projects in Colorado, we found the following overall:
• The cost premium for LEED-NC version 2.1 certification ranged from 1% to 6% of construction costs, for nine of eleven projects providing sufficient data (excluding Pikes Peak Regional Development Center and University of Denver Law School).
• While LEED cost premiums were shown for all projects, two of the projects (Fossil Ridge High School and Department of Labor and Employment Addition) noted that they were able to achieve LEED certification and complete the projects on schedule and under the original budget (hard cost increases were attributed to life-cycle decision making and design and construction standards, not LEED). Additionally, the Department of Labor and Employment Addition set their budget before LEED certification became a project priority.
Soft costs and benefits included the following items:
• Soft costs, including LEED registration and certification, LEED documentation, energy modeling and commissioning, average roughly 0.8% of the construction costs, or approximately $1 per sq. ft.
• Documentation costs for LEED certification submittals were difficult to quantify as the basis for the fee reporting was inconsistent with a reported range from less than $3,000 to a maximum of almost $60,000. Almost all of the project teams recommend reducing the documentation requirements. They recognize the importance of accountability provided by the LEED submittal review process; however, they view the documentation costs as a burden.
• Energy modeling averaged roughly $10,000 across nine projects reporting data, with eight projects reporting cost at or below $10,000 and one project reporting cost of nearly $35,000.
Smaller projects exhibited higher costs per square foot than larger projects. All of the teams designed and built their projects to at least 20% better than the requirements of ASHRAE 90.1-2001 Energy Standard for Buildings Except Low-Rise Residential Buildings (LEED requires only that the building meet the requirements of ASHRAE 90.1 or local code). The net present value of the energy savings associated with the project energy efficiency measures offset all of the LEED soft and hard costs in seven of the nine projects reporting energy savings data (counting the three CH2M HILL projects as one project).
Commissioning is a significant soft cost at an average of $0.55 per sq. ft., counting only one of the three CH2M Hill buildings, and accounts for roughly 60% of total soft costs. Commissioning ranged from $0.19 to $1.50 per sq. ft. based on 10 projects reporting data. The majority of the teams found it to be valuable, and commissioning costs were reportedly recovered soon in two projects (Snowmass Golf Clubhouse and Pikes Peak Regional Development Center). Although not quantified in this study, previous studies have reported a median payback period of less than five years for commissioning related activities.
The information provided by the project teams related to hard costs and cost savings of specific LEED-related decisions is too limited to provide budgeting guidance per LEED credit/point or overall. The costs for commissioning these projects are given in Figure A above. All projects except the City of Fort Collins Vehicle Storage Building incorporated enhanced commissioning. The projects did not break out fundamental and enhanced commissioning costs, with the exception of North Boulder Recreation Center and Pikes Peak Building Department.
The average commissioning cost is $0.55 per sq. ft. For all projects, the costs ranged from $0.19 to $1.50 per sq. ft. For projects over 100,000 sq. ft., the commissioning costs make up the majority of the project’s LEED-related soft costs (considering commissioning, energy modeling, LEED documentation and LEED certifications fees).
All project teams with the exception of two were strong advocates of the commissioning process. The City of Fort Collins Vehicle Storage Building and Colorado College Tutt Science Center found the commissioning process to be too documentation intensive.
Poudre School District (Fossil Ridge High School), the State of Colorado (Colorado Department of Labor and Employment Addition) and Aspen Skiing Company (Snowmass Golf Clubhouse) require commissioning on all their projects because they have found the benefits justify the costs, and have incorporated building commissioning into their design standards. So the decision to commission is not based on whether or not LEED certification is pursued.
Commissioning costs were recovered almost immediately at the Aspen Skiing Company Snowmass Golf Clubhouse and the Pikes Peak Regional Development Center through identification of cost saving opportunities.
Additional findings, future research
Below is a list of some of the remaining finding of the research.
• Life-cycle cost analysis (LCCA) is a valuable tool in creating a high-performance building. LCCA is employed on all projects for Poudre School District, Colorado College and the City of Boulder, and their designs are some of the most aggressive in terms of energy-efficiency.
• A few of the projects noted improvement in indoor air quality from the use of low-VOC materials. Colorado College has incorporated the low-VOC specifications into their design guidelines.
• A majority of the projects also enhanced the daylight levels and views in their facilities through the use of more and high performance glazing, interior glazing, light shelves and shading.
• All projects noted greater occupant satisfaction and the public relations value of having a LEED certified building. This benefits the commissioning industry as well.
• We were unable to draw general conclusions as to the costs and benefits relative to individual LEED certification levels.
• Most project teams are pursuing LEED on future projects. Project teams generally anticipate LEED-related costs will be lower on future projects, due to experience garnered from completing the certification process.
The work under this study has brought to light additional questions and potential areas for future study related to commissioning of LEED-NC projects. The energy savings reported by the project teams are, in a majority of the cases, based on savings predicted by design team computer simulation, and therefore, the findings related to cost-effectiveness rely heavily on the accuracy of these predictions. A re-analysis report will be valuable in confirming that these predicted energy savings were realized, and also will provide some measure of indication as to the effectiveness of the commissioning process in delivery savings. Many of the benefits quantified in other related studies as well as reported anecdotally under this study and elsewhere, such as operational and maintenance savings from commissioning, as well as reduced water consumption and related waste water fees, reduced tipping fees, increased productivity and decreased vacancy rates, were not quantifiable within the scope of this research project. Future research to quantify benefits in these areas will serve to strengthen the findings of this report.
The projects under study required independent, third-party commissioning regardless of building size. The current version of LEED (LEED-NC 2.2) alters this requirement to only require third-party commissioning on projects larger than 50,000 sq. ft. For projects less than 50,000 sq. ft., commissioning is required, but the commissioning agent can be a qualified member of the design or construction teams. This change to the commissioning requirements was intended to help minimize the cost impact of commissioning on smaller projects. Future study could quantify the cost and benefit impacts of this rating system change.
Costs and Benefits of Using LEED-NC in Colorado, Governor’s Office of Energy Management & Conservation, Rebuild Colorado, March 2007.
Mills, E., et al. The Cost-Effectiveness of Commercial-Buildings Commissioning, A Meta-Analysis of Energy and Non-Energy Impacts in Existing Buildings and New Construction in the United States (LBNL-56637), Lawrence Berkeley National Laboratory, Portland Energy Conservation Inc., Energy Systems Laboratory, Texas A&M University, December, 2004.
|LEED-NC v2.1 Project||LEED-NC Certification Level||Building Size (SF)||Year Completed||Construction Cost [$/SF]||LEED Cost Premium [$/SF]||NPV Energy Cost Savings [$/SF]||Net LEED Savings [$/SF]|
|NPV calculation assumes 6% discount rate over 20 years.|
|Aspen Skiing Company Snowmass Golf Clubhouse||Silver||10,000||2005||$370||($20.00)||no data|
|CH2M Hill North Building||Certified||112,600||2003||$156||($1.90)||$4.30||$2.40|
|CH2M Hill South Building||Certified||112,600||2002||$156||($1.90)||$4.30||$2.40|
|CH2M Hill West Building||Certified||164,500||2003||$156||($1.90)||$4.30||$2.40|
|City of Boulder N. Boulder Rec. Center||Silver||62,000||2002||$188||($8.70)||$10.40||$1.70|
|City of Fort Collins Vehicle Storage||Certified||15,250||2005||$129||($8.20)||$6.70||($1.50)|
|Colorado College Tutt Science Center||Certified||54,123||2004||$200||($9.20)||no data|
|Colorado Dept of Labor & Employment Addition||Certified||40,000||2004||$100||($3.30)||$2.30||($1.00)|
|Pikes Peak Regional Development Center||Silver||11,758||2005||$112||($0.90)||$5.10||$4.20|
|Poudre School District Fossil Ridge HS||Silver||288,685||2004||$122||($1.00)||$4.00||$3.00|
|University of Denver Law Building||Gold||210,000||2003||$230||($0.70)||$3.50||$2.80|
Editor’s note : This article is based on a paper presented during the 15th National Conference on Building Commissioning, hosted by Portland Energy Conservation, Inc., and held May 2 to May 4, in Chicago. This paper summarizes the results of a research project conducted in 2006 by Rebuild Colorado, a program of the Governor’s Office of Energy Management and Conservation, to examine the costs and benefits of 11 LEED-NC version 2.1 certified projects in Colorado. This is an edited version. The full proceedings from NCBC 2007, and proceedings from past conferences, are available at www.peci.org/ncbc .
CH2M HILL’s North, South and West Buildings
LEED commissioning costs for these three projects were as follows and include fundamental and enhanced commissioning: North Building = $21,350; South Building = $21,350; West Building = $31,170. The total of $73,870 was the lowest cost per square foot of all the buildings studied. The low cost of commissioning is attributed to the repetitive nature of these buildings and the fact that commissioning was provided by the owner (CH2M HILL). Interviews with the design team were not conducted for these buildings.
City of Boulder’s Recreation Center
Commissioning costs were $24,300 for fundamental commissioning and included $7,400 for enhanced commissioning. Since building occupancy began, there have been no unforeseen maintenance issues and predicted energy savings are reportedly being achieved. The City of Boulder performs cost/benefit analysis as standard practice, and would have likely incorporated most of the project energy systems (with the exception of the solar pool heating) had they not attempted LEED certification.
For future projects, the city has plugged in roughly 2% for LEED costs and recognizes that for smaller projects the percentage would likely be more. The 2% would cover commissioning as well.
Colorado’s Poudre School District
Fundamental and enhanced commissioning on Fossil Ridge High School cost $226,477, including the monitoring and verification plan. Commissioning started with Zach Elementary School in the late 1990s and is now part of all Poudre School District projects, including large remodels, and was part of the original budget. The school district has found that commissioning costs are warranted and frees up their maintenance personnel. The district feels that, as school districts get leaner and maintenance staff get reduced, third party commissioning is a benefit as it frees up maintenance staff to perform their core mission, provides better documentation and a better level of accountability, and allows maintenance to work alongside the commissioning agent, feeling comfortable knowing they are well represented.
Colorado’s Dept. of Labor
Commissioning for this building totaled $24,000 and was a good experience on the mechanical side, with lighting and water systems having some problems. The commissioning agent was brought on earlier in the design process (a testament to LEED) and the owner felt this shift benefited the project. The commissioning agent also reportedly gave the owner a stronger voice and helped implement the owner’s agenda. Occupant satisfaction was high with people noting the building “smelled good” and provided views for workers. The Office of the State Architect notes that many of the costs attributed to LEED are not truly LEED costs because items such as commissioning, high performance glazing and high efficiency boilers would have been included in the project had LEED not been pursued. Commissioning is considered a standard on all state projects now, and the state is moving to a continuous commissioning plan.
Note that the engineer of record on this project did not have LEED experience prior to the project. During the design and commissioning process, they came back several times and said LEED was causing them to do additional design work. However, requests for additional design fees were not granted.