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Commissioning Delivers Performance Assurance Verification a Logical Follow-up to Capital Investment
June, 2009
By Barbara Carss
Building commissioning is steadily gaining momentum as a sustainable construction and management practice that makes obvious economic sense. A design and development approach that emphasizes system integration and premium upfront capital investments to achieve long-term operating savings almost necessarily calls for a due diligence component to ensure the building is performing as envisioned and investors are getting what they’ve paid for.
“There are a lot of different definitions of what commissioning is. To me, it is verification of the performance of the building systems and components in accordance with design and contract documents,” says Moshe Wertheim, a consultant to the real estate industry and a member of the technical committee currently developing a Canadian Standards Association standard (CSA Z320) for commissioning. “That includes testing of all systems of the building during every mode of operation – day, night or failure mode. But commissioning is not just about systems, it is also the people running the systems who have to be trained.”
ASHRAE’s definition of commissioning is similar. It states: “The process focuses upon verifying and documenting that the facility and all its systems and assemblies are planned, designed, installed, tested, operated and maintained to the meet the owner’s project requirements.”
A 2004 study funded by the United States Department of Energy, The Cost-Effectiveness of Commercial Building Commissioning, suggests more vigilance is needed. Researchers found nearly 7,000 deficiencies in 113 surveyed buildings, with HVAC systems most commonly out of sync with designers’ intentions.
Subsequent correction of technical and/or operational errors improved energy efficiency, reduced maintenance and equipment replacement costs and enhanced occupant comfort. Across the 2004 survey sample, the median energy cost savings was 15% with a payback of less than one year. However, in some cases commissioning achieved savings of as much as 50%. (In the US, commissioning costs typically range from 20 to 40 cents US per square foot depending on the size and the complexity of the facility.)
“Three dollars invested in commissioning can return $11 in savings,” notes William Carson, the Commissioning Coordinator with the engineering consulting firm, The Mitchell Partnership, and Chair of the CSA Z320 committee. “If you’re doing a capital upgrade, anything you do should be commissioned.”
CATCH-UP FOR OLDER BUILDINGS
LEED (Leadership in Energy and Environmental Design) is driving much of the current commissioning activity in new buildings since it is a prerequisite for certification. The Canada Green Building Council’s new LEED Canada for Existing Buildings: Operations & Maintenance rating system also awards up to six points for commissioning measures, but the exercise is expected to be more complicated and costlier in older buildings that generally were not commissioned at their outset.
Indeed, specialists draw a distinction between recommissioning, which is a regular review and readjustment exercise evolving from original commissioning parameters, and retro-commissioning, which reviews, refines and updates equipment, operating procedures and systems integration in buildings where such a comprehensive assessment has not previously occurred.
“With retro-commissioning there are no benchmarks to work with and in many cases no drawings exist so you have to develop commissioning standards. You really have to start with a complete building audit,” Carson says.
A significant number of commercial, institutional and multi-residential buildings fall into this category. “You don’t have to go back too many years [in construction vintage] and you’re into a retro-commissioning opportunity for almost every building in the city,” he adds.
As recently as 1991, CSA and Canada Mortgage and Housing Corporation (CMHC) received a somewhat guarded response when they tried to gauge the real estate industry’s support for a program to develop commissioning best practices. Respondents to a survey at the time indicated they would be interested in voluntary guidelines, but expressed concern that civic officials might begin to mandate any model standard in municipal building by-laws. As for practices in their own buildings, survey participants reported that emergency systems such as fire safety, backup power and emergency lighting were the primary and sometimes only focus for commissioning.
“A lot of the buildings built in the 1960s, ‘70s and ‘80s weren’t commissioned. The building operator was expected to follow the operating manuals that the designers provided and figure it out,” recalls Ted Aldcroft, Manager of Capital Projects at Brookfield Properties Corporation’s iconic First Canadian Place in Toronto’s financial district. “These are buildings that were built at a time when you could buy a kilowatt-hour for less than three cents, and the systems were not that sophisticated. The automation systems were not always capable of doing everything they were touted to do. So the building operator would just go around and turn things on and off as he saw fit.”
OPTIMIZING TECHNOLOGY
Rising energy prices and dramatic technological advancements have since heightened the importance of the careful calibration and coordination of multiple building systems. Notably, researchers conducting the 2004 US study found nearly twice as many deficiencies per building in new construction than in existing structures, which was attributed to the greater number of complex and innovative systems in newer buildings.
Re-commissioning or retro-commissioning is similarly important when introducing new technology into an existing building. Aldcroft sees it as part of the process of optimizing building performance.
“It goes back to what the designer had intended to begin with and looks at available measures that can now achieve that using less energy, and it asks the question: if the building was built today, would you have designed it differently?” he advises. “You want to get a good designer involved and look at how you could impose more stringent and better energy efficiency controls.”
Researchers with CanmetENERGY, a research centre affiliated with Natural Resources Canada (NRCan), foresee load shaving and demand response spinoffs as well. “We see commissioning as something that needs to be done in a building in order to distribute the electricity properly. It can make it more efficient and at the same time reduce the use at peak hours,” says Alain Trépanier, a Specialist with CanmetENERGY’s Commercialization and Building Optimization division.
NRCan’s recently launched recommissioning initiative for commercial and institutional buildings also highlights some of the less complicated, tune-up related aspects of the process. “When you go into a building, at a very low cost you find problems, particularly in the HVAC systems, which can be corrected quite quickly. This is being achieved through simple measures and no [capital] investment and usually the payback is a year to a year-and-a-half,” Trépanier says.
STANDARDIZED APPROACH
Commissioning solely to LEED specifications excludes other critical inspections that would ensure compliance with contract documents since LEED’s commissioning requirements are geared largely to major energy-using systems. Wertheim stresses the equal importance of health and safety diligence in commissioning buildings systems.
“Unless separately contracted for, there is no mandatory process that delivers a commissioned individual building system, or a building as an integrated and optimized facility, to the owner,” he says. “The best and biggest example of a lack of integrated commissioning was in 2003, August 14, when there was a blackout [across Ontario and several US states]. People got stuck in elevators for hours. Emergency generators did not come on. Systems did not work and that’s because no one had performed a fully integrated commissioning or recommissioning.”
The CSA Z320 standard for building commissioning is meant to provide guidance and certainty in the burgeoning professional service area. A commissioning standard for health care facilities (CSA Z318.0.15) is already in place and the CSA had been contemplating a broader standard for some time before joining forces with the Mechanical Contractors Association of Canada (MCAC), which raised $125,000 to help fund the initial development of the standard.
“Our sector of the construction industry is very much involved in energy efficiency and our members are very familiar with the commissioning process, but not many buildings are fully commissioned,” notes Richard McKeague, MCAC’s President and Chief Operating Officer.
Expert committees are now working on the draft standard, which will be released for consultation later this year. The final version is expected to be confirmed by September 2010. Once the standard is in place, it will be made available in an electronic format. Initially the standard will focus on commissioning, but specifics related to recommissioning or retro-commissioning could be added in future appendices.
“We hope this will become a national standard and be embedded in the building codes, and we hope it would develop into a certification and education process,” Carson says. “That means we would end up with a consistent standard for commissioning providers.”
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