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55Planned versus fai luremain t enanceA building systems design engineer is nowexpected to provide considerably more inputto a life-cycle cost study of a building venturethan he was in the recent past. The currentdynamic nature of technology and the state ofthe art in the building industry have invalidated many of the statistical norms widelyused as recently as the last decade. In a life-cycle cost analysis, the three major ingredientscontrolled primarily by a systemdesigner are:first cost amortization, energy costs, andmaintenance! service! operations costs. Thelatter is discussed here with emphasis onmaintenance and service costs.

Maintenance and service costs M/Sshould be grouped into a single entry, simplybecause well-managed maintenance effortsinitiated during the environmental systemstart-up or debugging phase will reduce service costs during a buildings life to a minimum. Conversely, without well-managedmaintenance efforts, service costs can be aserious financial burden.An swe r th e se tw o quest ionsBefore attempting to quantify M/ S needs andsubsequent costs, tw o questions must be answered:

* How long does the owner intend to ownand manage the property?

* Are special skills that might be needed formaintenance and service of complex apparatus available in the area, and at what cost?The answer to the first question dictates

whether at time zero a planned maintenanceprogram should be put into effect. If theowner-developer intends to retain the prop-

erty for a long time, the only intelligent courseof action is to instigate such a program.Examples of this type of building are institutional buildings or commercial buildingsplanned for long-time ownership by majorreal estate holding firms or sole tenants.The other alternative, short-term ownership less than 1 5 years, might dictate thebreakdown maintenance or total dependencyon service approach. Whether by plan or not,this latter approach is employed in the majority of todays buildings. Examples of projectswhere this approach is intended are the so-called blue shoe commercial buildings wherethe owner-developer intends to retain ownership long enough to achieve a financiallybeneficial crossover point between equitygrowth and depreciation tax shelter benefits .

The pattern of annual MIS cost versusyears after start-up for long-term ownership isshown in Fig. 55-I. If a planned maintenanceprogram is followed, systemcomponents willbe in as good a condition after a projected 30or more years as at the beginning. The onlydeterrent to permanancy is obsolescence.Figure 55-2 represents a typical-MIS costcurve for short-term ownership. Generally,the crossover point occurs between 5 and 1 2years.

-- ,.___, _-, %___I -I- A c t u a l cost profi le

Y e a r s

C

A v e r a g e a n n u a l c o s t--SI.

Fig. 55-1. Annual M/S costs of a planned maintenance program.24 5

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24 6 X I / MAINTENANCE MANAGEMENT AND RELIABILITY

The answer to the first question not onlyaffects a des igners projection of life-cyclecost, but it will also seriously affect theselection of machinery and components. Theabsence of the answer to this question has innumerous cases resulted in system designersbeing severely criticized for misdirected decis ions . The results of this are that long-termowners are stuck with a property plannedotherwise, or rebound owners are not financially prepared for high M/ S costs.

Unless there exists a preprogrammed written maintenance program and procedure, it ismost likely that breakdown maintenance isthe operating procedure.

Cite exper i ence examp lesThe second question is best addressed by a fewbrief examples from personal experience.Of the many so-called total energy systemssystems which convert available fossil fuel

into all the necessary end-use energy forms forthe building system installed, several havebeen removed and replacedwith conventionalforms of available energy. Considering thatthe concept is valid, once installed, the investment monies spent, and unless extremelyil l conceived in energy and load balance, theprimary reason these plants have been removed is the unavailability of necessary skillsto maintain and service the machines.An absorption refrigeration system installedin a remote area is another example. A lackofreadily available maintenance and serviceskills led to its removal and replacement by avapor compression system.After addressing these two questions, adesigner has established the philosophy underlying the M/ S aspects of a system des ignand eliminated certain classes of machines orsubsystems. The next step is to assign M/Svalues to the selection of all system components or subsystems. This is perhaps the mostdifficult parameter of a system to quantify.

A v e r a g e a n n u a l c o s tw it h b re a kd o wnaIntenancQ7,_,,,_/

0

Ave raJ lannedmain tenance c o s tC r o s s o v e r po in t - i lYears

Fig. 55-2. Annual M/S costs of a breakdown maintenance program.