facility focus mance codes or objectives are identified. Buildings that were not commissioned at the time of construction can undergo retro commissioning — a systematic process that helps resolve many of the same issues that prompt a recommissioning process, while ensuring that a building and its systems are optimized to meet current operational requirements as closely as possible. Buildings with a track record of high energy use or a large number of com-fort complaints are good candidates for retro commissioning, as are structures with indoor environmental quality issues and new buildings that never operated properly. Buildings where space utilization or per-formance requirements have changed can also benefit from the retro commissioning process. ing of the original design intent and owner requirements, while differentiating between submitted and installed equipment, analyz-ing energy use and establishing operating baselines. Interviews with management, mainte-nance staff and building occupants also uncover patterns in building operation, including problem areas requiring focus during the next phase. A retro commissioning plan is developed to guide the site investigation phase. ■ Site investigation phase During this phase of the process, the team uses the findings of the previous two phases to identify potential improvement opportunities. A more detailed investigation of the building looks at operating systems, HVAC equipment, the building envelope, control systems, air balancing, indoor air qual-ity (IAQ) and other issues that are often the result of installation defects, deferred maintenance, control problems and building pressurization problems. Quick fixes are made and maintenance staff has the opportunity to participate in hands-on training. ■ Analysis phase Problems identified and data recorded during the site investigation phase are the focus during this phase of retro commis-sioning. After any additional testing is complet-ed, the team recommends solutions and includes estimated costs to implement the solutions and any associated energy/opera-tional savings that will result. ■ Corrective Phase After studying and prioritizing the recom-mended solutions, the team, which includes the building owner, selects those it wants to implement, oversees the implementation and commissions them to verify the effec-tiveness of the solutions and ensure they achieve the desired results. ■ Follow-up phase This phase of retro commissioning pro-vides an opportunity for the team to meet with building owners and maintenance staff to discuss the project, develop an ongoing commissioning plan and train staff on how to maintain the performance of the imple-mented improvements going forward. The on going commissioning plan should include a performance verification plan to establish an expected level of performance that can be monitored over time. A final retro commissioning report is pro-vided and any off-season testing that may be required is noted. Cleaning and maintenance supervisors under pressure to keep plants and facilities operating while reducing expenses appreci-ate the benefits of retro commissioning. By improving the performance of build-ing equipment and building systems inter-actions, the retro commissioning process contributes to lower operating costs and reduced energy consumption while mini-mizing breakdowns, reducing repairs and the associated costs and increasing the life expectancy of assets. Optimization strategies also produce improved IAQ and comfort. Meanwhile, retro commissioning directly addresses the causes of problems rather than the symptoms, ensures that the build-ing meets CFR as closely as possible and aligns strategic business goals and objec-tives with facility operations/infrastructure. At the same time, the process assists in achieving Leadership in Energy and Environmental Design (LEED) certification for Existing Buildings (EB) and improves a building’s ENERGY STAR rating. Finally, retro commissioning provides the opportunity to train maintenance staff to operate and maintain complex building sys-tems. This training, along with the benefits described above, helps cleaning and main-tenance staffs meet the health, productivity, sustainability and financial goals that define their jobs, resulting in enhanced building performance. CM Scott Gordon, LEED Accredited Professional for Operations and Maintenance (AP O+M), is the energy & sustainability product technical support manager for Johnson Controls Inc. He has over 30 years of experience in the mechanical contract-ing and engineering industry. Gordon holds a number of certifications from the Association of Energy Engineers (AEE) and is a member of the American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) committee GPC 0.2, The Commissioning Process of Existing Buildings and Assemblies, and GPC 1.2, The Technical Requirements to Commission Existing HVAC Systems. For additional information on Johnson Controls, visit www.JohnsonControls.com. Retro Commissioning Broken Down To help guide the process, the National Environmental Balancing Bureau (NEBB) has established six phases of retro com-missioning: ■ Contract phase In this first phase, a walk-through of the facility is conducted to inspect the overall condition of the building and the mechani-cal systems to determine their level of complexity. The inspection looks for details relative to access and construction, including the age and type of equipment. With respect to the heating, ventilation and air conditioning (HVAC) system, the inspection examines current and deferred maintenance issues, building pressure, air filters, outdoor air dampers, airside econo-mizer dampers, actuators and linkages, variable frequency drives, balancing valves on pumps and duct and pipe modifications. The process also includes interviews with management and the development of a project proposal. ■ Pre-site investigation phase The retro commissioning team reviews construction drawings and specifications, trend data from the building automation system (BAS), operation and maintenance manuals, test and balance reports, utility bills and maintenance records and repair and replacement orders. The goal is to gain a better understand-42 CM/Cleaning & Maintenance Management ® • August2011
CMM – Archives Aug 2011: 42
