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What Northern Ohio should know about building commissioning Industry Issues: Building Commissioning It involves owners, designers and contractors, all working together By Mary K. Dessoffy Mention "building commissioning" here in northeast Ohio, and you'll find that many people in the building trades-from architects to contractors-sometimes have only a vague idea of what the term means. But mention it to building owners in fast-growing communities like those in northern Virginia, and you'll find them knowledgeable about the process because it's one they've been working with for over a decade. For those interested in perusing Leadership in Energy and Environmental Design certification for their buildings, commissioning is a requirement. The U.S. Green Building Council defines commissioning of the energy systems as verification "that the building's energy related systems are installed, calibrated and perform according to the owner's project requirements." Yet a commissioning agent delivers so much more-working with mechanical engineers on the specifications, reviewing the sequences of operation, site inspections, and witnessing equipment testing. Building commissioning goes beyond the usual testing, adjusting and balancing (TAB) services that subcontactors provide. In the case of direct digital temperature controls, building commissioning should include point-to-point and functional performance testing to determine how well mechanical and electrical systems work together. Christopher Homola, PE and president of KTB Associates Consulting Engineers, LLC, in Olmsted Falls, Ohio, said that typically those activities are not, as many owners believe, part of the design and construction process, nor are they part of the standard operating and maintenance service contracts. "For successful building commissioning, there must be a clear appreciation of the scope, cost and timing of the commissioning activities," Homola says. "Invariably, commissioning requires comprehensive static and dynamic performance tests to identify operational deficiencies. This should begin in the schematic design phase and last at least one year after the project completion." So the systematic process of commissioning ensures that the building systems-HVAC, electrical, lighting, fire alarms, and others-are designed, built and operating properly. The entire process, from the design phase through construction administration, testing and validating, focuses on meeting the functionality of the design intent and the owner's satisfaction with the final product. Donald Dreier, executive vice president of Donley's, Inc. and president of the Builders Exchange, is a proponent of commissioning agents. A GC/CM for high-end projects, his Cleveland-based company has worked with the Cleveland Botanical Gardens, the Cleveland Institute of Music, and the two Cleveland stadiums. His preference is to employ the commissioning agent during the preconstruction phase. "Often the systems have not been integrated within the design, and issues come to play when controls are not correctly specified with the equipment installed. Or owners furnish equipment, and the coordination is not properly done." Dreier says. "We want to make sure early on that systems are fully integrated with each other throughout the design." Our neighbors to the south have given commissioning more attention than building owners here in northeast Ohio. Randy Dasher, director of construction for the Prince William County Public Schools in Virginia, currently has some 24 construction projects, including those in the design phase, under his direction. The school system has employed a commissioning agent for the past eight years. "I would never go back to not doing it. I feel that strongly about it," Dasher says, adding that the benefits of commissioning to a building owner are well worth the costs involved. "After we went through the commissioning process, and when all the items are addressed, you have a much more functional HVAC system with fewer complaints." Dasher adds that resolving issues before they occur, or just finding out what those issues are, is paramount to achieving a system that functions optimally. "It's just one more part of the construction cost of the building," he says. "All we're doing is identifying issues that do not comply with the contract documents." Fuel costs, sick buildings Increased fuel costs and the resulting complex and efficient HVAC systems, coupled with recent concerns about "sick building syndrome," have added to the headaches of building owners, architects, and contractors. Often the maintenance personnel and engineers who operate the state-of-the-art building systems need more extensive training to do so. That's why Homola says that building commissioning should also include training of the owner's operational and maintenance staff. In a similar vein, contractors need to fully understand the specification to bid the job (which may have a two- or three-year life span) and cut a profit, keeping in mind that the commissioning agent is required to hold them to high standards to meet the precise requirement of the specification. Dreier says it's important to clearly detail the mechanical and electrical contractors' roles in the commissioning process, which also helps subs accurately price their work. Although the technology is racing forward faster than many of us can keep up with it, in the words of architect Robert Baxter, "it is indeed here to stay." A construction contract administrator for Moseley Architects in Richmond, VA, he has teamed with commissioning agents for the past six years. He says that commissioning gives the architect the sense that the systems have been properly installed, that the building will be operating at its maximum efficiency, and that it confirms the performance criteria established in the design was met. "I don't know that cost is really a downside," he says. "If the building has been properly commissioned, then the HVAC systems and controls would realize a cost savings in the overall scheme of things." Baxter pointed out that some building owners routinely choose the lowest bidder, who needs to keep a close eye on material and labor costs, while still meeting specs. Those two goals can be at odds with each other, particularly when a commissioning agent is on site looking over the contractor's work and materials. From an architect's point of view, Baxter said, "that unless you have a commissioning agent to go out there and find everything, it's difficult. The agent knows where the bugs are and why they happen. Architects won't notice it because they just don't get into that kind of detail." FAQs: commissioning Who benefits? Ultimately, commissioning benefits building owners. It ensures they chose the system best suited for their needs, and that they got the equipment and installation they paid for. When building owners hear nothing at all from their occupants about the building's systems, they consider this a good omen. It means there are no hot or cold spots, drafty areas, or temperature fluctuations. In short-no complaints. So both building owners and the occupants benefit from commissioning. But commissioning is also helpful to architects, engineers and building occupants. For architects and engineers, commissioning is another tier, a failsafe, for tracking submittals and ensuring coordination among the mechanical trades. Agents also provide pre-functional and functional site observations, appropriate tasks for the agent because he or she is a knowledgeable third-party. In the pre-functional visit, the agent confirms that the exact equipment was delivered and installed correctly. During the functional visit, the agent makes sure the equipment is up and running. Contractors unfamiliar with this process may not be inclined to welcome a third party to "look over their shoulder," or they may think that their work will be unduly scrutinized. Although the agent will indeed be looking over the contractor's work, the truth is that contractors are better off when a commissioning agent is on the job. Just as Dreier points out, contractors get a cleaner set of construction documents to bid from. They also will enjoy improved coordination between the mechanical systems, the drawings and the specifications. Because the commissioning agent's goal is to have the project function properly at the end, the agent will contact the engineering team for clean, accurate answers to the contractor's RFIs during the construction phase. When contractors get good, on-time information, the amount of work that has to be undone and reconstructed is greatly minimized. Furthermore, once the commissioning agent approves the work, contractors can leave the job with confidence that their work meets the demands of the specification. They know that there is nothing standing in the way of their getting paid, and they can move on to the next job. Is it expensive? No. In fact, the initial cost is recovered many times over in reduced operating costs and lower maintenance costs. LEED requirements from the USGBC cite other important savings associated with commissioning: "reduced contractor callbacks, better building documentation, improved occupant productivity, and verification that the systems perform in accordance with the owner's project requirements." Commissioning fees are generally between 0.6 and 1.8% of the overall construction cost. What happens with new construction? First the certified building commissioning professional agent coordinates with the mechanical engineers during the design and specification writing phase. This involves an independent review of the documents for coordination between the mechanical systems and the controls system. Then the agent reviews the sequences of operation to ensure they fulfill the needs of the owner and how the building will be utilized. The agent checks that all instrumentation and monitoring points that will eventually be required to verify the mechanical systems are called out in the contract documents and functioning properly. During the construction administration phase, an independent review of equipment submittals and contractor shop drawings takes place. The goal here is to promptly identify and correct problems, especially those that involve coordination among the trades, while they are still on paper or before equipment is onsite. During the construction phase, the agent visits the site, making sure the contractors are adhering to construction methods identified in the contract documents. This verifies the owner is getting the equipment, and the equipment is getting installed, per the contract. At the completion of construction, the agent provides specific, detailed testing procedures and witnesses the equipment testing. Any piece of equipment or sequence of operation that does not perform as required is identified and reported so corrective actions can be taken. Can it help an existing building? Commissioning an existing building is called retrocommissioning. Over the life of a building, mechanical systems wear out and building utilization changes. Some examples: Lighting systems installed a few decades ago may be inefficient and inappropriate for today. Desktop computers have changed the look and function of the workstation. Addressing these issues can reduce operating costs and increase productivity. Temperature control systems may be unserviceable after 10 or 20 years. Older pneumatic systems can be largely non-functional due to age and poor maintenance. Identifying problems with control systems and correcting them can greatly improve equipment efficiency, temperature controls and employee productivity. Office buildings may have been originally fitted out for a few large offices. Now, with downsizing, these large spaces are divided into numerous smaller independent offices. Over the years, the mechanical systems and space temperature controls may not have been properly modified. The commissioning agent can identify these problems and provide specific direction for corrective actions. BXM Daniel L. Anthony is a certified building commissioning professional (CBCP) with the Association of Energy Engineers and president of Intelligent Building Systems, specializing in design services and commissioning of building automation systems and mechanical systems. Story from BXMagazine.com: http://www.bxmagazine.com/article.asp?ID=398 |
