Professional Engineers Of North Carolina

SPR 2014

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9 Spring 2014 the Professional Engineer toward more buildings. Most buildings are built to meet growth demand and don't replace aging ones. Given this notable trend of reduced R&R funding for nearly a decade, the current backlog may already be insurmountable. Te challenge is to recognize the additional cost of unfunded R&R and to develop new methods for generating those funds for new and future buildings. It is helpful for this analysis to defne the types of funding discussed. Tere are generally three categories of maintenance and repair funds — pre- ventive maintenance and minor repairs, unscheduled maintenance and R&R. In North Carolina, the frst category is funded through the operational budget of the agency occupying the building. Tis article focuses on the last category, which are funded through budgeted appropriations approved by the General Assembly. Historically, unscheduled maintenance has been funded through operational budgets. Over time, this funding strategy puts a signifcant strain on planned maintenance efective- ness as more and more dollars are diverted from preventive activities to reactive fxes. One directly observable efect of this trend is an increase in energy costs. Poorly maintained systems are less efcient, and reduced efciency directly translates to increased energy consumption. The basics To identify the impact of maintenance on life-cycle costs, consider a building's major systems and equipment that have a statistical failure rate as a function of time. An example of this is shown for a typical chiller, which has a life span of 20 years. While the level for minimal acceptable condition is somewhat subjective, this data translates to a predictable service life curve. Tis curve can represent most any building system, from mechanical HVAC systems to roofng or windows. Tough the rate of decline may change for various building systems, the life cycle for most major building components falls between 10 and 25 years. Te base assumption in producing this curve is that recommended maintenance was performed throughout the life of the equipment. Te slight increase in condition or perfor- mance of equipment at the early stage of operation identifes a normal period of optimization, a result of commissioning or other quality assurance methods. Te optimal condition is the level at which the equipment or system performs the intended or designed function 100% of the time. Te minimal acceptable condition is the statistical failure point, beyond which normal equipment could not perform the intended function. Te purpose of this life cycle view is to emphasize that in the latter half of service life, there is an inevitable loss of function, which translates to system downtime and by extension loss of building function. Te cost of that loss could be as low as uncomfortable occu- pants for short periods of time or as high as weeks of lost time and productivity while occupants are relocated and major damage from a failed system is repaired. Declining average $300 200 100 0 2003-04 2004-05 2005-06 2006-07 2007-08 2008-09 2009-10 2010-11 2011-12 2012-13 2013-14 2014-15 University allocation Agency allocation CostNothing_Spring14.indd 9 3/27/14 11:32 AM

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