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The core purpose of this report was to collect data that would be of use in promoting commissioning of new and existing buildings. A secondary purpose was to define methods for determining costs, benefits, and persistence of commissioning along with understanding national differences in the definition of commissioning. Research was grouped under two broad headings: Commissioning Cost-Benefit, and Commissioning Persistence. Commissioning Cost-Benefit Literature Review of Commissioning Cost-Benefit Methodologies Twelve studies were summarized, focused on studies where the cost-benefit methodologies were known. The majority were research studies of multiple buildings, and the studies ranged from research reports, databases, and marketing literature. These studies are summarized in three main aspects: 4. What problems were found, and the solutions, and 5. Non-energy benefits. Collected data was collated in spreadsheets for analysis and generation of charts of the key findings. Commissioning Persistence Literature Review on the Persistence of Commissioning Benefits This review summarized the findings from five studies encompassing 37 commissioning projects from across the USA. Persistence of savings was expressed as a percentage of the original claimed savings, after a specified time has elapsed after the project (e.g., 75 % after five years). In addition to evaluating project savings, the studies covered persistence at the level of specific measures, including the reasons for measures not persisting. Impact of Savings Normalization Method on Commissioning Persistence This study reviewed two weather normalization methods that are used in calculating energy savings from commissioning, and compared their impact on commissioning persistence claims. The two methods evaluated were: International Performance Measurement and Verification Protocol (IPMVP) A baseline regression model (or calibrated simulation model) is created based on the precommissioning energy use and recorded temperature/humidity. In the post-commissioning period, weather data is collected, and the regression model is used to predict what the energy use would have been if commissioning hadn't occurred. The actual energy use is subtracted from the modeled prediction, and this constitutes the energy saved. Normalized Annual Consumption (NAC) Similar basic principle to the IPMVP; a regression model (or calibrated simulation model) is created using baseline data. This model is applied to a standardized 'average' weather year based on the site location in order to calculate baseline annual energy use. In the postcommissioning period the regression model is recreated using post-energy and post-weather data, and this regression model is applied to the same 'average' weather year. The difference between the two modeled average years constitutes the savings. Examples of Tools for Enhancing Persistence of Commissioning Benefits There are a number of data collection and analysis tools that may be used for monitoring the persistence of commissioning improvements. This...

Premise plumbing systems constitute an essential component of the built environment by providing immediate access to clean, potable water and a safe, reliable means of removing wastewater from homes, businesses and other institutions. Plumbing systems evolved extensively throughout the 20 th century beginning with efforts in the 1920s to develop the technical understanding needed to support system design and regulation, much of which was initiated by then Secretary of Commerce Herbert Hoover to address a range of health and performance issues. Plumbing systems continue to evolve in response to current concerns about cost, water availability, environmental impacts and safety.A series of policy actions including the Safe Drinking Water Act of 1974, the Energy Security Act of 1980 and the Energy Policy Act of 1992 sought to improve water quality, water use efficiency, and energy efficiency. These changes led to notable achievements including the reduction of lead in plumbing products and the introduction of low-flow fixtures. For example, a typical single-family, detached home today uses 22 % less water for indoor purposes than it did two decades ago (DeOreo, et al., 2016). As a result, the flow rates within the piping networks and the corresponding residence times can be significantly different than those assumed under current design methods. Consequently, the assumptions surrounding the effectiveness of water treatment practices are not necessarily applicable, leading to the potential for decreased water quality. These and other realities have led to a situation in which plumbing systems are being designed, installed and operated in vastly different ways from what is supported by the technical data and understanding embodied in current codes, standards and practice.Plumbing design approaches, codes and standards have not kept pace with these changes, in large part because of the existence of significant technical knowledge gaps. Research is needed to address these gaps in support of water efficiency and water quality goals to ensure the effectiveness of these systems today and in the future. This report documents specific research needs to advance plumbing system design, operation and maintenance, as well as the standards, codes and guidelines that apply to these systems. The primary concerns that motivated this effort to identify premise plumbing research needs are water quality, water efficiency, and energy efficiency. Water quality is one of the biggest concerns as it directly affects the health and safety of building occupants, and is becoming an increasingly complex challenge. Water quality concerns fall into three main categories: metallic, chemical, and biological. The need for water efficiency is expected to become more pressing as a result of population growth, climate change and infrastructure challenges. The availability of water is largely a regional issue, and there are many areas around the U.S. and throughout the world that are subject to recurring water shortages, even under non-drought conditions....

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This report presents the use of a semi-automated commissioning tool for the energy retrocommissioning of the Performing Arts Center at Montgomery College in Rockville, Maryland. Researchers and field practitioners collaborated to implement the HVAC-Cx commissioning software tool in its first full-scale field test. HVAC-Cx aids building operators in decision-making by analyzing data using a set of expert rules governing the operation of the mechanical equipment. This publically-available software program has the capability to communicate with BACnet controllers to command the systems under test into their various modes of operation and to record system responses to facilitate some of the labor-intensive activities of retro-commissioning. These activities included monitoring building data under normal operation (operation monitoring) and active testing using a library of prefunctional tests and functional performance tests developed to evaluate the performance of both air-side and water-side systems. This report presents the results of the commissioning process and examines the effectiveness of the HVAC-Cx commissioning tool.