34R-

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BASI
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 AACE® International Recommended Practice No. 34R-05

BASIS OF ESTIMATE
TCM Framework: 7.3 – Cost Estimating and Budgeting

Rev. October 5, 2021

Note: As AACE International Recommended Practices evolve over time, please refer to web.aacei.org for the latest
revisions.

Any terms found in AACE Recommended Practice 10S-90, Cost Engineering Terminology, supersede terms defined in
other AACE work products, including but not limited to, other recommended practices, the Total Cost Management
Framework, and Skills & Knowledge of Cost Engineering.

Contributors:
Disclaimer: The content provided by the contributors to this recommended practice is their own and does not necessarily
reflect that of their employers, unless otherwise stated.

October 5, 2021 Revision:

Todd Pickett, CCP CEP FAACE (Primary Contributor) Dave Kyle, CCP CEP

May 4, 2014 Revision:

Todd Pickett, CCC CEP (Primary Contributor) Stephen M. Jacobson, CCC
Peter R. Bredehoeft, Jr. CEP Carlton W. Karlik, PE CEP
Ted A. Downen Christopher L. Kinney
Larry R. Dysert, CCC CEP Donald F. McDonald, Jr. PE CCE PSP
Bruce G. Elliott, CCC Bernard A. Pietlock, CCC CEP
John K. Hollmann, PE CCE CEP Richard A. Selg, CCE
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This document is copyrighted by AACE International and may not be reproduced without permission. Organizations may obtain permission
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AACE® International Recommended Practice No. 34R-05
BASIS OF ESTIMATE
TCM Framework: 7.3 – Cost Estimating and Budgeting

October 5, 2021

TABLE OF CONTENTS

Table of Contents ..........................................................................................................................................................1

1. Introduction ...............................................................................................................................................................3
2. Estimate Basis Development Process ........................................................................................................................4
2.1. Inputs to the BOE ................................................................................................................................................4
3. Estimate Basis Format and Content ..........................................................................................................................5
3.1. General ...............................................................................................................................................................5
3.1.1. Purpose ........................................................................................................................................................5
3.1.2. Project and Estimate Objectives ..................................................................................................................5
3.1.3. Project Scope Description ............................................................................................................................5
3.1.4. Project Execution Plan Summary .................................................................................................................6
3.1.5. Construction, Fabrication, and Operating Parameters ................................................................................6
3.1.6. Estimate Classification .................................................................................................................................6
3.2. Methodology ......................................................................................................................................................7
3.2.1. Estimating Tools...........................................................................................................................................7
3.2.2. Coding Structure ..........................................................................................................................................7
3.3. Design Basis ........................................................................................................................................................7
3.3.1. Units of Measure .........................................................................................................................................7
3.3.2. Currency and Exchange Rates ......................................................................................................................7
3.3.3. Rounding ......................................................................................................................................................7
3.4. Quantity Basis .....................................................................................................................................................8
3.5. Cost Basis ............................................................................................................................................................8
3.6. Planning Basis .....................................................................................................................................................9
3.7. Bulk Commodity Material ...................................................................................................................................9
3.8. Labor ...................................................................................................................................................................9
3.9. Demolition ..........................................................................................................................................................9
3.10. Allowances ......................................................................................................................................................10
3.11. Assumptions ...................................................................................................................................................10
3.12. Exclusions........................................................................................................................................................10
3.13. Exceptions .......................................................................................................................................................10
3.14. Risks and Opportunities ..................................................................................................................................10
3.15. Containments .................................................................................................................................................10
3.16. Contingencies .................................................................................................................................................11
3.17. Management Reserve .....................................................................................................................................11

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3.18. Reconciliation .................................................................................................................................................11

3.19. Benchmarking .................................................................................................................................................11
3.20. Estimate Quality Assurance ............................................................................................................................11
3.21. Estimating Team .............................................................................................................................................11
3.22. Attachments ...................................................................................................................................................12
3.22.1. Attachment A: Estimate Deliverables Checklist .......................................................................................12
3.22.2. Attachment B: Reference Documents .....................................................................................................12
3.22.3. Additional Attachments ...........................................................................................................................12
4. Level of Detail in the Basis of Estimate ....................................................................................................................12
4.1. Level of Project Definition ................................................................................................................................12
4.2. Cost Value of the Project ..................................................................................................................................12
4.3. Type of Project ..................................................................................................................................................13
4.4. Other Factors ....................................................................................................................................................13
References ...................................................................................................................................................................13
Contributors ................................................................................................................................................................13

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1. INTRODUCTION

AACE International’s Total Cost Management (TCM) Framework [1] identifies a basis of estimate (BOE) document
as a required component of a cost estimate. As a recommended practice (RP) of AACE International, the template
outlined in the following sections provides guidelines for the structure and content of a cost basis of estimate.

In the TCM Framework, the BOE is characterized as the one deliverable that defines the scope of the project, and
ultimately becomes the basis for change management. When prepared correctly, any person with capital project
experience can use the BOE to understand and assess the estimate, independent of any other supporting
documentation. A well-written BOE achieves those goals by clearly and concisely stating the purpose of the
estimate being prepared (i.e., cost study, project options, funding, etc.), the project scope, pricing basis,
allowances, assumptions, exclusions, cost risks and opportunities, and any deviations from standard practices. In
addition, the BOE is a documented record of pertinent communications that have occurred and agreements that
have been made between the estimator and other project stakeholders.

A well-prepared basis of estimate will:

• Document the overall project scope.

• Communicate the estimator’s knowledge of the project by demonstrating an understanding of scope and
schedule as it relates to cost.
• Communicate the uncertainty associated with the estimate and alert the project team to potential cost risks
and opportunities.
• Provide a record of key communications made during estimate preparation.
• Provide a record of all documents used to prepare the estimate.
• Act as a source of support during dispute resolutions.
• Establish the initial baseline for scope, quantities and cost for use in cost trending throughout the project.
• Provide the historical relationships between estimates throughout the project lifecycle.
• Facilitate the review and validation of the cost estimate.
• Highlight deficiencies in estimate preparation that may impact the estimate.
• Be aligned with the estimate plan document.

Although the primary intent of this RP is to provide a guideline for the topics and contents to be included in a
typical BOE, there are a few points of significance worth noting. A basis of estimate should:

• Be factually complete, but concise.

• Be able to support facts and findings.
• Identify estimating team members and their roles.
• Describe the tools, techniques, estimating methodology, and data used to develop the cost estimate.
• Identify other projects that were referenced or benchmarked during estimate preparation.
• Be prepared in parallel with the cost estimate.
• Establish the context of the estimate, and support estimate review and validation.
• Qualify any rates or factors that are referenced either in the estimate or BOE; e.g. productivity can be
expressed as either units/time (linear feet/hour) or time/units (hours/linear foot).

This RP is intended to be a guideline, not a standard. It is understood that not all organizations that prepare
estimates employ the same processes and practices, and therefore, may opt to use this information either in part
or in its entirety.

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2. ESTIMATE BASIS DEVELOPMENT PROCESS

This section defines the main steps and discusses issues to be considered while preparing a BOE. In general, a
separate BOE will be developed for each individual estimate, but the content for projects within a program should
be integrated where appropriate. Some projects may lend themselves towards having a single estimate basis for all
individual scopes of the project.

Figure 1 highlights the requirements of the estimate basis development process.

Prepare Draft Estimate Basis Estimate Basis

Estimate Basis Reviews Approval

Updates Changes

Inputs
• Project Scope
• Execution Plan
• Methodology:
• Quantity Basis
• Cost Basis
• Clarifications, Qualifications, and
Assumptions
• Exclusions and Exceptions
• Risk Analysis
• Supporting Documents

Figure 1. – Estimate Basis Development Process

2.1. Inputs to the BOE

The BOE should leave the reader with a clear understanding of the information and assumptions the estimator has
used in developing the estimate. It should clearly define:
• Scope of the estimate.
• Methodologies used to develop the estimate.
• Sources and quality of supporting data.
• All inputs to the estimate.
• All required outputs.
• Any areas of uncertainty within the estimate including significant risks.

The quality of the estimate and BOE should be such that the reader can make clear business decisions based on
the provided information and support project system analyses (lessons learned, claims, historical, etc.)

The BOE should reflect the owner’s specifications for the BOE. It is the responsibility of the lead estimator to
develop an estimate basis which will satisfy the owner’s needs. Where multiple contractors are involved, the BOE
must clearly define the scope of the estimate. The basis should note portions of the overall project scope that fall
outside of the estimate, which the reader may otherwise expect to be included (e.g., mining equipment is
included, but the initial mine excavation is executed by another contractor and is excluded from the estimate).

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The final version of the estimate plan may be used as the starting point for the BOE by carrying over common
elements, wording, and formatting from the estimate plan. Estimate requirements should be reviewed to assure
consistency.

Preparation of the BOE document during the estimate preparation process is essential as key information may
later be forgotten and not documented.

It is important to note that there can be a significant difference in a BOE for a deterministic estimate (Class 3, 2 and
1) – where the primary method of cost development is through the use of semi-detailed or detailed unit costs –
and a conceptual estimate (Class 5 and 4), which is primarily developed through the use of cost estimating
relationships (e.g., equipment factoring). The extent to which the following sections of the basis of estimate
document are completed will be dependent on the type of project, the class of estimate, and other variables. It is
recommended to keep the document concise, but to include as much of the following relevant information as
possible.

Additional information regarding the level of detail in the BOE is provided later in this document.

3. ESTIMATE BASIS FORMAT AND CONTENT

This section describes the suggested topics and contents included in a typical BOE. The extent to which each of the
sections below can be completed as indicated is highly dependent on the intended class of estimate, and the level
of definition available.

The following describes the suggested topics and contents included in a typical BOE.

3.1. General

3.1.1. Purpose

In this initial section of a basis of estimate, the estimator should provide a brief and concise description for the
total project. The type of project should be identified (i.e., new facilities, addition to existing, revamp of existing,
etc.), as well as the type and capacity of the facility, the location of the facility, and the overall timing of the
project.

The purpose of the estimate sets the focus for the remainder of the document. Identify whether the estimate is a
part of a requirement for approval to proceed to the next phase of the project, a special study, to update the cost
control baseline, etc. Secondary purposes are to establish a basis for project control, to quantify resource
requirements, and provide owner decision-makers with an appropriate level of confidence in the estimate.

3.1.2. Project and Estimate Objectives

Describe the alignment of the cost estimate with project objectives (i.e., cost or schedule driven); and cost, pricing,
and risk strategy.

3.1.3. Project Scope Description

The intent of this section is to provide the reader with a clear understanding of the major components within the
scope of the project, and major components not included in the project. This section should be organized to
correspond with the project’s work breakdown structure (i.e., plant, building, floor, etc.). A semi-detailed

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description of the scope of work should be provided for each major segment of the project. Identify any major
pieces of equipment or components. It’s also good practice to indicate the primary trades that will be involved
with the project. Be as thorough as necessary, without being overly descriptive, so as to adequately explain the
scope of work being estimated.

3.1.4. Project Execution Plan Summary

Identify the execution assumptions that the estimate is based upon including:
• The contracting strategy including the labor type (union, open shop, mixed, or other) and the planned
labor work week and applicable shift schedules (e.g.: 8 hours per day x 5 days per week.) used in the
estimate. Explain how overtime hours and related cost allowances were determined.
• Labor sources (number of local, travel cards, temporary foreign workers, etc.).
• The procurement strategy including identification of free issued equipment or material (and whether
included in the estimate) and overseas purchases.
• The fabrication strategy including locations of off-site fabrication.
• Modularization strategies identifying module construction locations, and possible double or triple
handling costs of modules, or off-site assembly of models into super-modules.
• All project breakdown structures used to identify the work activities in the estimate.
• Ensure alignment with the cost estimate and schedule assumptions and requirements.
• The summary schedule (by facility, phase, unit, and commodity/discipline). Note any special schedule
events that impact costs and are reflected in the estimate. Examples are:
• weather windows (shipping and site)
• operating outages
• tie-ins
• work week
• extended overtime
• union contract expiration dates
• peak manpower periods
• planned downtime (e.g., holidays, planned evacuations in existing facilities)
• known and pending regulatory/environmental issues

3.1.5. Construction, Fabrication, and Operating Parameters

Note all assumptions and information sources relating to items such as average annual weather conditions at the
job site along with maximums, minimums and time of year they occur. Known soil conditions are summarized (e.g.,
clay/rock, topsoil depth, permafrost, water table, underground aquifers, etc.). Distance to nearest major
population centers, infrastructure availability, material sourcing locations, etc. should be documented. A checklist
may be used for identifying other applicable location parameters.

3.1.6. Estimate Classification

The AACE International estimate classification should be identified for the type of estimate being prepared, along
with reasons or justification used in the selection of the estimate classification.

AACE Professional Guidance Document PGD-01 (Guide to Cost Estimate Classification Systems) [2] provides a
roadmap and annotated table of contents for finding the AACE recommended practice (RPs) relating to the type of
cost estimate being prepared.

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3.2. Methodology

The BOE should indicate the primary estimating methodology used to prepare the cost estimate. This should
include documentation of the use of cost resources, historical data and project benchmarking. Documenting the
level of effort or man-hours used in preparation of the estimate is also recommended.

3.2.1. Estimating Tools

Describe all software applications, including version, and how they were used (e.g., simulated quantities, internal
database, interface software to load productivity rates into estimating program).

3.2.2. Coding Structure

Attach the final project code of accounts, project work breakdown structure (WBS), cost breakdown structure
(CBS), or other specified coding and formatting requirements as an appendix. Include a table in the appendices
showing all attributes assigned to each code.

3.3. Design Basis

Company standards will typically specify the technical and project information required for the classification of the
estimate that is being prepared. In this section, the estimator will identify the types and status of engineering and
design deliverables that were provided to prepare the estimate including any technical basis assumptions. Two
attachments to the estimate basis should be referenced: 1) an estimate deliverables checklist that is aligned with
the company’s standard project process; and 2) a listing of all engineering drawings (including revision number and
date), a well as other design information, such as specifications, equipment lists, units of measure (imperial vs.
metric), etc.

In addition, it may be useful to document specific quantity metrics for particular projects, such as overall
excavation and backfill quantities, overall concrete volumes, overall piping quantities, etc.

3.3.1. Units of Measure

State the type of units of measure (i.e., metric, imperial) and any exceptions that were used.

3.3.2. Currency and Exchange Rates

State the currencies used (e.g., US Dollars - USD). Indicate the exchange rates and basis for foreign purchases used.

3.3.3. Rounding

Define the rounding principles used.

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3.4. Quantity Basis

For each commodity, clearly define the final source of all quantities and the methodology used to develop them
such as: detailed material take-offs, based on sketches, standard detail designs, and computer-simulated take-offs,
or factored. The extent of input from vendors, discipline specialists/experts and project execution personnel
should be stated. State the design stage that the quantities reflect. State the method used to calculate any
quantity allowances. The portion of quantities taken from a 3D model for each commodity will be defined.
Quantities taken from computer models must include an explanation of safeguards that were in place to ensure
quality, consistency, and verification of the completeness of the quantities extracted from the model. Clearly
identify all quantities that are not developed from engineering design including:
• Sketch based quantities
• Forced detail quantities from software applications
• Factored quantities

A table summarizing the final quantity development and take-off basis for each commodity can be a helpful quick
reference.

Ensure that external providers of quantities (e.g., engineering) provide a clear basis of their assumptions for
inclusion in the BOE.

3.5. Cost Basis

Describe the methods and sources used for determining all material, labor and subcontract pricing. Identify the
following:

• Pricing sources for all major equipment (vendor quotes, historical data, etc.).
• Bulk material and commodity pricing sources, including any discount strategies.
• The pricing source for all labor hours, and all labor productivity adjustments. Provide appropriate detail if
productivities vary by trade and/or location within the project (plant, etc.).
• All wage rates used (including crew/craft rates, craft mix, etc.). Identify all items included in all-in rates (if
used).
• Pricing source and methodology for construction indirects.
• Pricing source for all start-up costs.
• Pricing source and methodology for all home office costs (project management, engineering, design, etc.).
Document the basis for any contractor fee costs.
• Pricing source and methodology for costs such as freight, taxes, duties, etc.
• Pricing source for any owner’s costs included in the estimate.
• Currency exchange rates if applicable, as well as the stability and/or volatility of rates.
• Escalation indices used, and the method of calculation (including duration).
• Contingency development and basis.
• Location factors used and the basis for these factors.
• Influence of local market conditions.
• Capital costs vs. expense costs, or other categorization as necessary.
• Any other pricing factors or external influences that may have a significant impact on project cost should
be identified.

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3.6. Planning Basis

This section documents the project management, engineering, design, procurement, fabrication, and construction
approaches to the project. The contracting and resource strategies should be identified, as well as any assumptions
that were made with regard to the workweek schedule (hours worked per day, days worked per week, shifts
worked per day, etc.) and planned use of overtime. Any assumptions made regarding constructability,
modularization, use of specialized construction equipment should also be noted here.

The overall project schedule and key milestones should be identified.

3.7. Bulk Commodity Material

Indicate the percent of bulk material costs which were from budget quotes, firm quotes, in-house pricing or other
sources. Separately address material supplied to fabricators and material for site installation. A table could be used
to summarize this as well.

Address any special considerations such as whether a concrete batch plant will be used at site. Bulk material is to
be separately identified as owner, contractor, or sub-contractor supplied.

3.8. Labor

• Construction Labor Costs

Describe how crew mixes, union contracts, non-union wages, benefits and other factors were used to
build-up the labor rates. Attach a copy of the craft labor agreements when available. Identify crew mixes
including portions of apprentices, foremen, general foremen, journeymen. For each commodity, identify
the crew mix used including the portion for each trade (i.e. the mix of pipefitters, welders, carpenters,
electricians, etc.)

• Construction Labor Productivity

Explain how labor productivity was determined for each commodity. It should address items such as:
adjustments to a base productivity for labor density, facility complexity, excessive overtime, weather,
shifts, labor quality, labor availability, worker facilities (e.g., lockers, washrooms, lunchrooms) proximity to
work areas and support facilities (e.g., tool crib, warehouse, material staging area), greenfield vs.
brownfield vs. revamp vs. shutdown conditions, soil conditions, elevated work, geographic location, and
any other factors affecting productivity. Provide a description of the basis of the base productivity
including the types of projects included, 3rd party software database, in-house data, etc. A table should be
provided in the estimate plan showing how each factor was applied.

• Construction Work Week and Overtime

The provider should specify the final basis regarding the construction work week schedules and use of
shifts and overtime.

3.9. Demolition

This addresses general demolition of decommissioned and/or abandoned facilities. Demolition for revamps is
typically included with each commodity/discipline. Describe the general demolition scope and how the quantities
and costs were developed.

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3.10. Allowances

In this section, identify the level and types of allowances used in the estimate. Describe the basis for the common
estimating allowances such as material take-off allowances, overbuy allowances, design allowances for engineered
equipment, congestion allowances, working height allowances, etc.

This section should also describe any other costs that have not been detailed in the body of the estimate, such as
lump-sum allowances for specific areas of scope or any other factored costs not described elsewhere in the
estimate basis.

3.11. Assumptions

Any other assumptions made by the estimator but not documented elsewhere in the estimate basis should be
included in this section. This may include such assumptions as an adequate labor supply being available, adequate
funding available, site conditions, etc. Minor assumptions may become major assumptions throughout the life of
the project; therefore, it is recommended to document all assumptions regardless of their anticipated impact.

3.12. Exclusions

In this section, the estimator should document all potential items of cost which a reviewer might associate with
the project, but for which no costs have been included in the estimate. Asbestos abatement, removal of hazardous
wastes, acquisition of land, taxes, financing costs, licensing costs, etc. are examples of potential items that may
need to be identified.

3.13. Exceptions

The estimator should identify any anomalies or variances to your organization’s estimating practices. This section
should document any significant deviations from the project and/or engineering deliverables normally required for
the applicable class of estimate. A good practice is to provide a checklist as an attachment to the BOE that will
document any exceptions that are identified. This checklist should correspond to your organization’s estimating
practices.

3.14. Risks and Opportunities

Any areas of the estimate containing significant risk or opportunity should be identified. If a formal risk analysis
study has been prepared then it should be described (e.g. methodology, technique, etc.). In particular, this section
should identify those cost elements that have been identified with high or very high risk or opportunity values. The
risk analysis report (or summary) should be provided as an attachment to the BOE.

3.15. Containments

Containments are cost elements in the estimate related to measures included to prevent and/or mitigate the
identified risks. The activities are identified in the risk analysis report. These may impact not only cost but also
duration.

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3.16. Contingencies

Contingency is a cost element of the estimate used to cover the uncertainty and variability associated with a cost
estimate, and unforeseeable elements of cost within the defined project scope. Contingency covers inadequacies
in complete project scope definition, estimating methods, and estimating data. Contingency specifically excludes
changes in project scope, and unforeseen major events such as earthquakes, prolonged labor strikes, etc. The
amount of contingency included in the estimate should be identified, as well as the methods used to determine
the contingency amount. If risk analysis techniques were utilized to develop the contingency amount, the
associated confidence level should also be identified.

3.17. Management Reserve

Contingency is not intended to cover the costs associated with changes in project scope. If the project needs to
provide an allowance for anticipated changes in scope, or to cover the costs for items that may be required but
have not yet been specifically identified as being included in the current project scope, then that amount of cost,
typically referred to as management reserve, should be identified here.

The intended purpose and use of management reserve should be clearly identified. The approval process,
management and tracking of the management reserve should also be clearly identified.

3.18. Reconciliation

Provide an overview of the major differences between the current estimate and the last published estimate
prepared for this project. Identify the cost impacts due to scope changes, pricing updates, labor productivity
adjustments, estimate refinement, etc. A more detailed reconciliation or cost trending report can be provided as
an additional attachment if necessary.

3.19. Benchmarking

This section should document any comparisons of overall estimate metrics, ratios, and factors with similar
projects, historical data, and industry data. References used in the benchmark comparisons should be similar in
process type and overall value. If significant variations of the estimated values versus the benchmarks exist those
inconsistencies should be identified, explained, and/or reconciled. A more detailed benchmark analysis report may
be included as an attachment to the BOE.

3.20. Estimate Quality Assurance

Since estimate reviews are the means for testing the quality of the estimate, this section of the BOE should identify
all estimate reviews that have taken place to date, and any additional reviews that are proposed to take place. All
review comments or analysis should be included as an attachment to the BOE. In case of an external review this
section should include who executed the review, when it was conducted, and what references were used.

3.21. Estimating Team

In this section, all members of the estimating team should be identified, including roles and responsibilities.

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3.22. Attachments

Several supporting documents will generally be included with the basis of estimate.
1) Attachment A: Estimate Deliverables Checklist

3.22.1. Attachment A: Estimate Deliverables Checklist

Attach a completed estimate deliverables checklist indicating the project and engineering deliverables that should
be provided to support preparation of the estimate for the associated estimate classification, and whether they
were in fact available during preparation of the estimate.

3.22.2. Attachment B: Reference Documents

Document the drawings, manuals, texts, notes, specifications, and other references used in developing the
estimate. Identify the revisions and date of issue for key documents.

3.22.3. Additional Attachments

Include any other attachments that may be necessary or required (reconciliation report, benchmarking report, risk
analysis report, escalation calculations, etc.).

4. LEVEL OF DETAIL IN THE BASIS OF ESTIMATE

It is often not a simple matter to determine the amount of detail that should be provided in a BOE. Several factors
may come into play during the preparation of the estimate that will help determine the level of detail. However, it
is the estimator’s best judgment that will ultimately determine the appropriate level.

4.1. Level of Project Definition

Estimates are prepared at various stages of a project. A more detailed estimate will generally require a more
detailed BOE, however that is not always the case.

A conceptual estimate will most likely be based on a limited amount of scope but may require a more detailed
BOE. It's not uncommon for a BOE for a conceptual estimate (e.g. Class 5 or Class 4) to be more thorough than one
prepared for a more detailed estimate (e.g. Class 1 or Class 2) because there are often more assumptions made at
the conceptual stage of an engagement that require greater documentation.

Conversely, there may be times when the project definition is so complete or simplistic that a BOE does not
require a great amount of detail. A three or four page document may be sufficient to convey the information
provided in the BOE.

4.2. Cost Value of the Project

Typically, a more expensive project will require a more detailed BOE. However, projects of lesser cost can require
an extensive BOE to fully communicate major assumptions that constrain or reduce the cost.

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4.3. Type of Project

The type of project can also affect the BOE. For example, the BOE for a direct purchase (e.g., single piece of large
equipment) may be less detailed than a BOE for a construction project

4.4. Other Factors

Other factors that affect the level of detail in a BOE are: work breakdown structure (WBS), consideration for new
technologies, contracting strategy, etc.

The BOE should contain a concise level of detail to fully support the review of the estimate by those that have not
been involved in the preparation of the estimate. The BOE provides a definition of the scope of the engagement as
estimated and should establish the basis for change management subsequent to publication of the estimate.

REFERENCES

[1] H. L. Stephenson, Ed., Total Cost Management Framework: An Integrated Approach to Portfolio, Program and
Project Management, 2nd ed., Morgantown, WV: AACE International, Latest revision.
[2] AACE International, Professional Guidance Document (PGD) 01, Guide to Cost Estimate Classification,
Morgantown, WV: AACE International, Latest revision.
[3] AACE International, Recommended Practice No. 10S-90, Cost Engineering Terminology, Morgantown, WV:
AACE International, Latest revision.

CONTRIBUTORS

Disclaimer: The content provided by the contributors to this recommended practice is their own and does not
necessarily reflect that of their employers, unless otherwise stated.

October 5, 2021 Revision:

Todd Pickett, CCP CEP FAACE (Primary Contributor)
Dave Kyle, CCP CEP

May 4, 2014 Revision:

Todd Pickett, CCC CEP (Primary Contributor)
Peter R. Bredehoeft, Jr. CEP
Ted A. Downen
Larry R. Dysert, CCC CEP
Bruce G. Elliott, CCC
John K. Hollmann, PE CCC CEP
Stephen M. Jacobson, CCC
Carlton W. Karlik, PE CEP
Christopher L. Kinney
Donald F. McDonald, Jr. PE CCE PSP
Bernard A. Pietlock, CCC CEP
Richard A. Selg, CCE

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