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AACE International Recommended Practice No. 18R-97

COST ESTIMATE CLASSIFICATION SYSTEM – AS APPLIED IN ENGINEERING, PROCUREMENT, AND CONSTRUCTION FOR THE PROCESS INDUSTRIES
TCM Framework: 7.3 – Cost Estimating and Budgeting Rev. November 29, 2011
Note: As AACE International Recommended Practices evolve over time, please refer to www.aacei.org for the latest revisions.

Contributors: PeterChristensen, CCE (Author) Larry R. Dysert, CCC CEP (Author) Jennifer Bates, CCE Jeffery J. Borowicz, CCE CEP PSP Peter R. Bredehoeft, Jr. CEP Robert B. Brown, PE Dorothy J. Burton Robert C. Creese, PE CCE John K. Hollmann, PE CCE CEP
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Kenneth K. Humphreys, PE CCE Donald F. McDonald, Jr. PE CCE PSP C. Arthur Miller Todd W. Pickett, CCC CEP Bernard A. Pietlock, CCCCEP Wesley R. Querns, CCE Don L. Short, II CEP H. Lance Stephenson, CCC James D. Whiteside, II PE
AACE® International Recommended Practices

AACE® International Recommended Practice No. 18R-97

COST ESTIMATE CLASSIFICATION SYSTEM – AS APPLIED IN ENGINEERING, PROCUREMENT, AND CONSTRUCTION FOR THE PROCESS INDUSTRIES
TCM Framework: 7.3 – Cost Estimating and Budgeting November 29, 2011 PURPOSEAs a recommended practice of AACE International, the Cost Estimate Classification System provides guidelines for applying the general principles of estimate classification to project cost estimates (i.e., cost estimates that are used to evaluate, approve, and/or fund projects). The Cost Estimate Classification System maps the phases and stages of project cost estimating together with a genericproject scope definition maturity and quality matrix, which can be applied across a wide variety of process industries. This addendum to the generic recommended practice (17R-97) provides guidelines for applying the principles of estimate classification specifically to project estimates for engineering, procurement, and construction (EPC) work for the process industries. This addendum supplementsthe generic recommended practice by providing: • • a section that further defines classification concepts as they apply to the process industries; and a chart that maps the extent and maturity of estimate input information (project definition deliverables) against the class of estimate.

As with the generic recommended practice, an intent of this addendum is to improve communications among all ofthe stakeholders involved with preparing, evaluating, and using project cost estimates specifically for the process industries. The overall purpose of this recommended practice is to provide the process industry definition deliverable maturity matrix which is not provided in 17R-97. It also provides an approximate representation of the relationship of specific design input data and designdeliverable maturity to the estimate accuracy and methodology used to produce the cost estimate. The estimate accuracy range is driven by many other variables and risks, so the maturity and quality of the scope definition available at the time of the estimate is not the sole determinate of accuracy; risk analysis is required for that purpose. This document is intended to provide a guideline, not astandard. It is understood that each enterprise may have its own project and estimating processes and terminology, and may classify estimates in particular ways. This guideline provides a generic and generally acceptable classification system for process industries that can be used as a basis to compare against. This addendum should allow each user to better assess, define, and communicate their ownprocesses and standards in the light of generally-accepted cost engineering practice.

INTRODUCTION For the purposes of this addendum, the term process industries is assumed to include firms involved with the manufacturing and production of chemicals, petrochemicals, and hydrocarbon processing. The common thread among these industries (for the purpose of estimate classification) is their reliance...