1、Designation: E917 05 (Reapproved 2010)Standard Practice forMeasuring Life-Cycle Costs of Buildings and BuildingSystems1This standard is issued under the fixed designation E917; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the ye
2、ar of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.INTRODUCTIONSeveral methods of economic evaluation are available to measure the economic performance of abuilding or buildin
3、g system over a specified time period. These methods include, but are not limitedto, life-cycle cost (LCC) analysis, the benefit-to-cost ratio, internal rate of return, net benefits,payback, multiattribute decision analysis, risk analysis, and related measures (see Practices E964,E1057, E1074, E1121
4、, E1765, and E1946). These methods differ in their measure and, to some extent,in their applicability to particular types of problems. Guide E1185 directs you to the appropriatemethod for a particular economic problem. One of these methods, life-cycle cost (LCC) analysis, isthe subject of this pract
5、ice. The LCC method sums, in either present-value or annual-value terms, allrelevant costs associated with a building or building system over a specified time period. Alternative(mutually exclusive) designs or systems for a given functional requirement can be compared on thebasis of their LCCs to de
6、termine which is the least-cost means of satisfying that requirement over aspecified study period.1. Scope1.1 This practice establishes a procedure for evaluating thelife-cycle cost (LCC) of a building or building system andcomparing the LCCs of alternative building designs or systemsthat satisfy th
7、e same functional requirements.1.2 The LCC method measures, in present-value or annual-value terms, the sum of all relevant costs associated withowning and operating a building or building system over aspecified time period.1.3 The basic premise of the LCC method is that to aninvestor or decision ma
8、ker all costs arising from an investmentdecision are potentially important to that decision, includingfuture as well as present costs.Applied to buildings or buildingsystems, the LCC encompasses all relevant costs over adesignated study period, including the costs of designing,purchasing/leasing, co
9、nstructing/installing, operating, main-taining, repairing, replacing, and disposing of a particularbuilding design or system.2. Referenced Documents2.1 ASTM Standards:2E631 Terminology of Building ConstructionsE833 Terminology of Building EconomicsE964 Practice for Measuring Benefit-to-Cost and Savi
10、ngs-to-Investment Ratios for Buildings and Building SystemsE1057 Practice for Measuring Internal Rate of Return andAdjusted Internal Rate of Return for Investments in Build-ings and Building SystemsE1074 Practice for Measuring Net Benefits and Net Savingsfor Investments in Buildings and Building Sys
11、temsE1121 Practice for Measuring Payback for Investments inBuildings and Building SystemsE1185 Guide for Selecting Economic Methods for Evaluat-ing Investments in Buildings and Building SystemsE1369 Guide for Selecting Techniques for Treating Uncer-tainty and Risk in the Economic Evaluation of Build
12、ingsand Building SystemsE1765 Practice for Applying Analytical Hierarchy Process(AHP) to Multiattribute Decision Analysis of Investments1This practice is under the jurisdiction of ASTM Committee E06 on Perfor-mance of Buildings and is the direct responsibility of Subcommittee E06.81 onBuilding Econo
13、mics.Current edition approved April 1, 2010. Published July 2010. Originallyapproved in 1983. Last previous edition approved in 2005 as E917 05. DOI:10.1520/E0917-05R10.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annua
14、l Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.Related to Buildings and Building SystemsE1946 Practice for Measuring Cost Ri
15、sk of Buildings andBuilding SystemsE2204 Guide for Summarizing the Economic Impacts ofBuilding-Related Projects2.2 Adjuncts:Discount Factor Tables Adjunct to Practices E917, E964,E1057, E1074, and E112133. Terminology3.1 DefinitionsFor definitions of terms used in the prac-tice, refer to Terminologi
16、es E631 and E833.4. Summary of Practice4.1 This practice outlines the recommended procedures forcomputing the LCCs associated with a building or buildingsystem over a specified time period. It identifies and givesexamples of objectives, alternatives, and constraints for anLCC analysis; identifies pr
17、oject data and general assumptionsneeded for the analysis; and presents alternative approaches forcomputing LCCs. This practice requires that the LCCs ofalternative building designs or systems be compared over acommon time period to determine which design or system hasthe lowest LCC. This practice a
18、lso states that uncertainty,unquantifiable effects, and funding constraints shall be consid-ered in the final analysis. It identifies the recommendedcontents of an LCC report, describes proper applications of theLCC method, provides examples of its use, and identifieslimitations of the method. A com
19、prehensive example of theLCC method applied to a building economics problem isprovided in Appendix X1.5. Significance and Use5.1 LCC analysis is an economic method for evaluating aproject or project alternatives over a designated study period.The method entails computing the LCC for alternative buil
20、dingdesigns or system specifications having the same purpose andthen comparing them to determine which has the lowest LCCover the study period.5.2 The LCC method is particularly suitable for determiningwhether the higher initial cost of a building or building systemis economically justified by reduc
21、tions in future costs (forexample, operating, maintenance, repair, or replacement costs)when compared with an alternative that has a lower initial costbut higher future costs. If a building design or system specifi-cation has both a lower initial cost and lower future costsrelative to an alternative
22、, an LCC analysis is not needed toshow that the former is the economically preferable choice.5.3 If an investment project is not essential to the buildingoperation (for example, replacement of existing single-panewindows with new double-pane windows), the project must becompared against the “do noth
23、ing” alternative (that is, keepingthe single pane windows) in order to determine if it is costeffective. Typically the “do nothing” alternative entails noinitial investment cost but has higher future costs than theproposed project.6. Procedure6.1 Follow these steps in calculating the LCC for a build
24、ingor building system:6.1.1 Identify objectives, alternatives, and constraints (seeSection 7).6.1.2 Establish basic assumptions for the analysis (see 8.1).6.1.3 Compile cost data (see 8.2).6.1.4 Compute the LCC for each alternative (see Section 9).6.1.5 Compare LCCs of each alternative to determine
25、theone with the minimum LCC (see 10.1).6.1.6 Make final decision, based on LCC results as well asconsideration of risk and uncertainty, unquantifiable effects,and funding constraints (if any) (see 10.2, 10.3, 10.4, and 10.5).7. Objectives, Alternatives, and Constraints7.1 Specify the design or syste
26、m objective that is to beaccomplished, identify alternative designs or systems thataccomplish that objective, and identify any constraints thatlimit the available options to be considered.7.2 An example is the selection of a space heating systemfor a new house. The system must satisfy the thermal co
27、mfortrequirements of the occupants throughout the heating season.Available alternatives (for example, various gas furnaces, oilfurnaces, heat pumps, and electric baseboard heaters) may havedifferent types of fuel usage with different unit costs, differentfuel conversion efficiencies, different initi
28、al costs and expectedmaintenance and repair costs, and different lives. Systemselection will be constrained to those fuel types available at thebuilding site.8. Data and Assumptions8.1 Basic AssumptionsEstablish the uniform assumptionsto be made in the economic analysis of all alternatives. Theseass
29、umptions usually include, but are not limited to, theconsistent use of the present-value or annual-value calculationmethod, the base time and study period, the general inflationrate, the discount rate, the marginal income tax rate (whererelevant), the comprehensiveness of the analysis, and theoperat
30、ional profile of the building or system to be evaluated.8.1.1 Present-Value Versus Annual-Value CalculationsThe LCCs of project alternatives must be calculated uniformlyin present-value or annual-value terms. In the former, all costsare discounted to the base time; in the latter, all costs areconver
31、ted to a uniform annual amount equivalent to the presentvalue when discounted to the base time.8.1.2 Study PeriodThe study period appropriate to theLCC analysis may or may not reflect the life of the building orsystem to be evaluated. The same study period must be used foreach alternative when prese
32、nt-value calculations are used. Anannual-value LCC may, under certain restrictive assumptions,be used to compare alternatives with different study periods(see 9.2.3). The following guidelines may be useful forselecting a study period for an LCC analysis:8.1.2.1 When analyzing a project from an indiv
33、idual inves-tors standpoint, the study period should reflect the investorstime horizon. For a homeowner, the study period for ahouse-related investment might be based on the length of timethe homeowner expects to reside in the house. For a commer-cial property owner, the study period might be based
34、on the3Available from ASTM International Headquarters. Order Adjunct No.ADJE091703. Original adjunct produced in 1984. Adjunct last revised in 1984.E917 05 (2010)2anticipated holding period of the building. For an owner/occupant of a commercial building, the study period mightcorrespond to the life
35、of the building or building system beingevaluated. For a speculative investor, the study period might bebased on a relatively short holding period. For investments bygovernment agencies and large institutions, specific internalpolicies often direct the choice of study period.8.1.2.2 When LCC analyse
36、s of alternative building systemsor design practices are performed for general informationrather than for a specific application (for example, governmentor industry research to determine the cost effectiveness ofthermal insulation or high-efficiency heating and coolingequipment in typical installati
37、ons), the study period will oftencoincide with the service life of the material or system (but belimited to the typical life of the type of building where it is tobe installed). When the service life is very long, a moreconservative choice for the study period might be used if theuncertainty associa
38、ted with the long-term forecasting of costssubstantially reduces the credibility of the results.8.1.2.3 Regardless of the type of investor or purpose of theanalysis, use the same study period for all categories of costswhen calculating the present value of any cost associated witha project. Furtherm
39、ore, when comparing alternative designs orsystems on the basis of their present-value LCCs, use the samestudy period for each investment alternative.8.1.2.4 When the study period selected is significantlyshorter than the service life of the building or system evaluated,it is important that a realist
40、ic assessment of the projects resale(or residual) value at the end of the study period be included inthe LCC analysis. Even if the building will not be sold at thattime, the resale value will likely have a significant impact onthe LCC.8.1.3 InflationGeneral price inflation is the reduction inthe pur
41、chasing power of the dollar from year to year, asmeasured, for example, by the percent increase in the grossnational product (GNP) deflator over a given year. LCCanalyses can be calculated in constant-dollar terms (net ofgeneral inflation) or in current-dollar terms (including generalinflation). If
42、the latter is used, a consistent projection of generalprice inflation must be used throughout the LCC analysis,including adjustment of the discount rate to incorporate thegeneral inflation rate.8.1.3.1 When income tax effects are not included in theLCC analysis, as in the case of LCC evaluations of
43、nonprofitbuildings and owner-occupied houses (without financing), it isusually easier to express all costs in constant dollars. Pricechanges for individual cost categories that are higher or lowerthan the rate of general inflation can be included by usingdifferential rates of price change for those
44、categories.8.1.3.2 When income tax effects are included in the LCCanalysis, it is usually easier to express all costs in currentdollars because income taxes are tied to current-dollar cashflows rather than constant-dollar cash flows.8.1.4 Discount RateThe discount rate selected shouldreflect the inv
45、estors time value of money. That is, the discountrate should reflect the rate of interest that makes the investorindifferent between paying or receiving a dollar now or at somefuture point in time. The discount rate is used to convert costsoccurring at different times to equivalent costs at a common
46、point in time.8.1.4.1 Select a discount rate equal to the rate of return onthe next best available use of funds. Where the discount rate islegislated or mandated for a given institution, that rate takesprecedence.8.1.4.2 A discount rate that includes general price inflationover the study period is r
47、eferred to as the “nominal” discountrate in this practice. A discount rate expressed in terms net ofgeneral price inflation is referred to as the “real” discount rate.8.1.4.3 Anominal discount rate, i, and its corresponding realdiscount rate, r, are related as follows:r 51 1 i1 1 I2 1ori 5 1 1 r!1 1
48、 I! 2 1 (1)where:I = the rate of general price inflation.8.1.4.4 Use a real discount rate if estimates of future costsare expressed in constant dollars, that is, if they do not includegeneral inflation.8.1.4.5 Use a nominal discount rate if estimates of futurecosts are expressed in current dollars,
49、that is, if they includegeneral inflation.8.1.4.6 When alternative building or system designs arecompared using the LCC method, use the same discount rate ineach LCC computation.8.1.5 ComprehensivenessDifferent levels of effort can beapplied in undertaking an LCC analysis. The appropriate levelof comprehensiveness depends upon the degree of complexityof the problem, the intended purpose of the evaluation, thelevel of monetary and nonmonetary impacts contingent uponthe investment decision, the cost of the different levels ofcomprehensiveness, and the resources available
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