"Project Closeout" marks the formal transition between the construction and operation phases in the building lifecycle. To ensure a smooth transition it's essential that Building Managers, Operators, and Stewards are equipped with the information they will need to optimally care for and maintain the building.
To capture critical project data and prepare projects for optimal operational excellence, Harvard has identified various levels of Closeout Documentation / Operations and Maintenance Readiness for projects depending on their scope of work. The requirements are captured Harvard's Green Building Standards.
Project teams and Project Managers should submit all closeout documentation in accordance with the appropriate Asset Management Program. Example documentation turnover may consist of:
- O&M Manuals
- As-built drawings
- Updated Sequences of Operations
- The Commissioning System Manual
- Additional Training materials
- Final project Energy Model with input/output summary report
For a comprehensive list of best practices refer to ASHRAE Guideline 4-2008. In addition, Harvard closeout documents should be filed with the PIRC in accordance with their acceptance requirements.
The Measurement and Verification (M&V) process is used during building occupancy, or post-installation for a system retrofit project, to quantify the savings delivered by the project's energy conservation measures (ECM). The actual energy savings are then compared to the projected energy savings expected for the ECM's during the design phase to ensure the building and its energy systems are functioning properly. The M&V process can also inform Project Teams and Project Managers by giving real world performance information for future projects considering similiar ECM's. In order to ensure a successful M&V process, it is important that the design team, owner, contractors, and M&V consultant draft an M&V plan together and specify any necessary submetering equipment.
For capital projects, new construction or major retrofits, energy modeling software is typically used to estimate the amount of savings which will be expected for the project once all ECM's have been installed. Using protocols published by the International Performance Measurement and Verification Protocol (IPMVP), 12 full months a energy data are collected after the building has been fully occupied and compared to energy model data. For large projects using energy modeling IPMVP option C and option D are used for guidance when drafting the M&V plan. In order to accurately compare the actual and modeled energy data, the energy model is calibrated in order to account actual weather over the past year, changes to system operations during the first year of occupancy, and account for the actual quantity and duration of building occupants. Energy model calibration is further refined by using trending information from the projects submeters and/or BAS reports.
When implementing one or multiple ECM's in an existing building, IPMVP option A and option B can be referenced for quantifying the amount of savings actually delivered by the ECM implementation. Energy modeling is not necessarily used for estimating the amount of savings to be expected, but engineering calculations may be used a substitute. Careful consideration should be used to ensure the necessary amount of energy usage is being trended in order to compare actual energy usage to the calculated energy usage.
Several guidelines exist which can help the Project Team when deciding how to draft and implement an M&V plan:
- IPMVP guideline
- FEMP: M&V Guidelines for Federal Energy Projects Version 3.0
- ASHRAE Guideline 14
Commissioning is the process of verifying that a building's systems are operating as intended. These systems could include heating and cooling systems, refrigeration systems, domestic water systems, envelope assemblies, and building management systems. The documents that typically guide whether a system is functioning correctly are the Basis of Design (BOD), the Owner Project Requirements (OPR), design documents, and manufacturer documents. Ideally, commissioning starts early in the design and construction process with document reviews, though the core of the effort traditional takes place during functional testing of equipment immediately following construction completion. A plan should be put in place provide some type of existing building commissioning (re-commissioning, retro-commissioning, ongoing commissioning) to ensure that optimal building operations continue. Whether a building has been newly constructed or has existed for many years, there are different methods of commissioning to help verify the building is operating as designed.
New Building Commissioning (Cx)
When undertaking the construction of a new building or even renovating a part of a building, commissioning is critical to the success of the project. According to a research study conducted by the Lawrence Berkeley National Laboratory1, the median cost of commissioning for commercial new construction is $1.16 per square foot (or 0.4% of the overall construction cost) with a median simple payback of only 4.2 years when considering only utility costs. When choosing to pursue commissioning for a new construction project, it's important to engage a commissioning authority (CxA) early in the design process. This will allow the project to maximize the benefits of commissioning, as this can reduce the cost associated with change orders in a typical project by identifying problems upfront before construction.
A system that is typically overlooked during the commissioning is the envelope, or enclosure, of the building because it doesn't actively use energy. A 2007 study found that out of 17,000 construction defect claims examined, 69% were due to moisture-related defects in the building enclosure systems.2 With a commissioning cost estimate of only 0.3% to 1.0% of the total construction cost, it doesn't take a lot to avoid these problems and the compounding problems if left unattended - both energy-related and non-energy related (e.g. mold growth as it affects occupant health).
Existing Building Commissioning (EBCx)
Older buildings may not have undergone a commissioning process during their lifetime. Between the time of completion and the present, deferred maintenance and changing operational characteristics can have a significant energy and cost impact. According to the Lawrence Berkeley National Laboratory study mentioned previously1, the median cost of commissioning for existing commercial buildings is $0.30 per square foot (0.4% of the overall construction cost) with a median simple payback of only 1.1 years. There are three distinct types for commissioning existing buildings: re-commissioning, retro-commissioning, and continuous commissioning. The following methods should not be used in-place of traditional commissioning processes for new construction projects, but rather support long-term optimization of facility operations.
Re-commissioning / Retro-commissioning (ReCx or RetroCx)
Re-commissioning refers to the process of commissioning of a building that has already been commissioned. Retro-commissioning refers to the commissioning of a building that has not yet undergone a traditional Cx process. Both have similar objectives as it relates to returning the building back to its original design intent and/or optimizing operations and typically differ only in the scale of effort required to document how the building should be operating. This type of commissioning is ideal for buildings that are experiencing elevated levels of energy compared to peer benchmarks. Since this is a point-in-time event, Energy Star suggests that re-commissioning be conducted every three to five years to ensure optimal operations over the long term.
Automated Continuous or Ongoing Commissioning (CCx, ACCx, or OGCx)
This type of existing building commissioning incorporates monitoring equipment within the building to track energy usage. Often software based, CCx providers typically monitor the building automation system (BAS) in real- or near real-time to discover inconsistences between how the building should be operating and how it is actually operated. The manner in which this information is harnessed to drive change in facility operations is up to the owner, and it is recommended that someone knowledgeable with building controls take the lead in reviewing reported deficiencies and coordinate resolutions with maintenance staff.
Sources and Additional Information
Several guidelines exist which can help guide the commissioning process: