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Chapter 15

Cost Control

Digital Hardhat System

The Need

The cost and time required to travel between construction sites limits the

ability of personnel to quickly respond to problems at remote sites and to

communicate issues between all necessary decision makers. Also, it is

difficult to organize and transmit multimedia project information (digital

pictures, video, electronic documents, and audio recordings) so that others

can access current project information in an intuitive and timely manner.

The Digital Hardhat (DHH) technology enables dispersed users to capture

and communicate multimedia field data to collaboratively solve problems,

and collect and share information. The DHH is a pen-based personal

computer with special Multimedia Facility Reporting System software that

allows the field representative to save multimedia information into a

project-specific database, which is then accessible to others through the

World Wide Web. The mobile unit and a hardhat

The Technology

The Digital Hardhat (DHH) is a pen-based personal computer (PC) running a Windows

operating system, which is used to collect multimedia information such as text, sound,

video, and images. This pen-based computer can also be used to communicate between

the construction site and other locations using various connection methods including a

wireless network connection, which enables personnel to roam around the site and video

teleconference live with others to solve problems collaboratively. In addition, special

software called Multimedia Facility Reporting (MFR) System allows the field

representative to save multimedia information into a project-specific database accessible

through the internet. The project information collected through the system will help

Digital Hardhat Using a whiteboard Multimedia Information on MFR

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252 Chapter 15 Cost Control

document site conditions, progress, and problems in an organized manner so the

information can be retrieved easily as needed by any project participant. In the application

of this system, immediate reductions in travel cost will be the most obvious benefit;

however, costs associated with more quickly resolving issues, reducing construction

claims, and fewer time delays will be the ultimate benefit of this technology.

15.1 COST CONTROL AS A MANAGEMENT TOOL

The early detection of actual or potential cost overruns in field construction activities is

vital to management. It provides the opportunity to initiate remedial action and increases

the chance of eliminating such overruns or minimizing their impact. Since cost overruns

increase project costs and diminish profits, it is easy to see why both project management

and upper-level management must become sensitive to the costs of all project activities.

An important byproduct of an effective cost reporting system is the information that

it can generate for management on the general cost performance of field construction activities.

This information can be brought to bear on problems of great interest to project

management. The determination of current project status, effectiveness of work progress,

and preparation of progress payment requests require data generated by both project planning

and cost control reporting systems. Project cost control data are important not only

to project management in decision-making processes but also to the companyÕs estimating

and planning departments because these data provide feedback information essential for

effective estimates and bids on new projects. Thus a project control system should both

serve current project management efforts and provide the field performance database for

estimating future projects.

15.2 PROJECT COST CONTROL SYSTEMS

The design, implementation, and maintenance of a project cost control system can be considered

a multistep process. The five steps, shown schematically in Figure 15.1, form

the basis for establishing and maintaining a cost control system. The following questions

regarding each step in the implementation of the cost control system must be

addressed.

1. Chart of Cost Accounts. What will be the basis adopted for developing estimated

project expenditures, and how will this basis be related to the firmÕs general accounts

and accounting functions? What will be the level of detail adopted in defining

the project cost accounts, and how will they interface with other financial

accounts?

2. Project Cost Plan. How will the cost accounts be utilized to allow comparisons

between the project estimate and cost plan with actual costs as recorded in the field?

Howwill the project budget estimate be related to the construction plan and schedule

in the formation of a project cost control framework?

3. Cost Data Collection. How will cost data be collected and integrated into the cost

reporting system?

4. Project Cost Reporting. What project cost reports are relevant and required by

project management in its cost management of the project?

5. Cost Engineering. What cost engineering procedures should project management

implement in its efforts to minimize costs?

These are basic questions that management must address in setting up the cost control

system. The structure of cost accounts will be discussed in this chapter.

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15.4 Cost Coding Systems 253

Figure 15.1 Steps in cost control.

15.3 COST ACCOUNTS

The first step in establishing a cost control system for a construction job is the definition

of project-level cost centers. The primary function of the cost account section of a chart of

accounts is to divide the total project into significant control units, each consisting of a given

type of work that can be measured in the field (see Fig. 15.2). Once job cost accounts are

established, each account is then assigned an identifying code known as a cost code. Once

segregated by associated cost centers, all the elements of expense (direct labor, indirect

labor, materials, supplies, equipment costs, etc.) constituting work units can be properly

recorded by cost code.

The design, structure, and development of a cost coding system and its associated set

of expense accounts have a significant impact on the cost management of a company or

project. The job cost accounting system is essentially an accounting information system.

Therefore, management is free to establish its own chart of accounts in any way that helps

it in reaching specific financial and cost control objectives, whether these objectives are

related to general company performance, to the control of a specific project, or to specific

contract requirements.

15.4 COST CODING SYSTEMS

A variety of cost coding systems exist in practice, and standard charts of accounts are

published by organizations such as the American Road Builders Association, Associated

General Contractors, and the Construction Specifications Institute. In many industries, cost

codes have a company-wide accounting focus emphasizing expense generation based on a

departmental breakdown of the firm. In some construction firms, cost systems have a structured

sequence corresponding to the order of appearance of the various trades or types of

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254 Chapter 15 Cost Control

Figure 15.2 List of typical project expense (cost) accounts.

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15.5 Project Cost Code Structure 255

Table 15.1 Classification of Accounts: Major Divisions

in Uniform Construction Index

Cost Centers

0 Conditions of the contract

1 General requirements

2 Site work

3 Concrete

4 Masonry

5 Metals

6 Carpentry

7 Moisture prevention

8 Doors, windows, and glass

9 Finishes

10 Specialties

11 Equipment

12 Furnishings

13 Special construction

14 Conveying system

15 Mechanical

16 Electrical

construction processes typical of the companyÕs construction activity. In most construction

companies, detailed project cost accounts such as those shown in Figure 15.2 are used. This

method recognizes the fact that construction work is project oriented and that to achieve the

cost management goal of maximizing profit, projects must be accounted for individually.

One project may be a winner while another is losing money. Such situations may be masked

in the accounting system unless job cost accounts are maintained on a project-by-project

basis. Therefore, both billings (revenue) and cost (work in progress) accounts are typically

maintained for each project. The actual account descriptions or designations vary in accordance

with the type of construction and the technologies and placement processes peculiar

to that construction. Building contractors, for instance, are very interested in accounts that

describe the cost aspects of forming and casting structural concrete as used in building

frames. Heavy construction contractors, on the other hand, are interested in earthworkrelated

accounts such as grading, ditching, clearing and grubbing, and machine excavation.

Standard cost accounts published by the American Road Builders Association emphasize

these accounts, while the Uniform Construction Index (UCI), published by the Construction

Specifications Institute, emphasizes building-oriented accounts. A breakdown of the major

classifications within the UCI cost account system is shown in Table 15.1. A portion of the

second level of detail for classifications 0 to 3 is shown in Figure 15.3.

15.5 PROJECT COST CODE STRUCTURE

The UCI Master Format code as used by the R. S. Means Building Construction Cost Data

identifies three levels of detail. At the highest level the major work classification as given

in Table 15.1 is defined. Also at this level major subdivisions within the work category

are established. For instance, 30-level accounts pertain to concrete while 031 accounts are

accounts specifically dealing with concrete forming. In a similar manner, 032 accounts are

reserved for cost activity associated with concrete reinforcement.

At the next level down, a designation of the physical component or subelement of the

construction is established. This is done by adding three digits to the work classification

two-digit code. For instance, the three-digit code for footings is 158. Therefore, the code

031158 indicates an account dealing with concrete forming costs for footings.

At the third and lowest level, digits specifying a more precise definition of the physical

subelement are used. For instance an account code of 0311585000 can indicate that this

account records costs for forming concrete footings of a particular type (see Fig. 15.4). At this

level the refinement of definition is very great, and the account can be made very sensitive

to the peculiarities of the construction technology to be used. Further refinement could

differentiate between forming different types of footings with different types of material.

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256 Chapter 15 Cost Control

Figure 15.3 Detailed codes for classification within Uniform Construction Index.

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15.5 Project Cost Code Structure 257

Figure 15.4 UCI cost (line item) structure in the master format code.

At this level, the cost engineer and construction manager have a great deal of flexibility in

reflecting unique aspects of the placement technology that lead to cost fluctuations and thus

must be considered in defining cost centers.

Large and complex projects in industrial and energy-related construction may require

cost codes that reflect additional information, such as the project designation, the year in

which the project was started, and the type of project. Long and complex codes in excess

of 10 digits can result. An example of such a code is shown in Figure 15.5. This code,

consisting of 13 digits, specifically defines the following items:

1. Year in which project was started (2004)

2. Project control number (15)

3. Project type (5 for power station)

4. Area code (16 for boiler house)

5. Functional division (2, indicating foundation area)

6. General work classification (0210, indicating site clearing)

7. Distribution code (6, indicating construction equipment)

Figure 15.5 Classification of accounts: typical data structure for a computerized cost code.

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258 Chapter 15 Cost Control

The distribution code establishes what type of resource is being costed to the work process

(i.e., clearing), the physical subelement (i.e., foundations) in what area of which project.

Typical distribution codes might he as follows:

1. Labor

2. Permanent materials

3. Temporary materials

4. Installed equipment

5. Expendables

6. Construction equipment

7. Supply

8. Subcontract

9. Indirect

Clearly, a high concentration of information can be achieved by proper design of the cost

code. Such codes are also ideally suited for data retrieval, sorting, and assembly of reports

on the basis of selected parameters (e.g., all construction equipment costs for concrete

forming on project 10 started in a given year). The desire to cram too much information

into cost codes, however, can make them so large and unwieldy that they are confusing to

upper-level management.

15.6 COST ACCOUNTS FOR INTEGRATED PROJECT MANAGEMENT

In large and complex projects, it is advantageous to break the project into common building

blocks for control both of cost and time. The concept of a common unit within the project

that integrates both scheduling and cost control has led to the development of the work

breakdown approach. The basic common denominator in this scheme is the work package,

which is a subelement of the project on which both the cost and time data are collected

for project status reporting. The collection of time and cost data based on work packages

has led to the term integrated project management. That is, the status reporting function

has been integrated at the level of the work package. The set of work packages in a project

constitutes its work breakdown structure (WBS).

The work breakdown structure and work packages for control of a project can be

defined by developing a matrix similar to the one shown in Figure 15.6. The columns of

this matrix are defined by breaking the down project into physical subcomponents. Thus

we have a hierarchy of levels that begins with the project as a whole and, at the lowest level,

subdivides the project into physical end items such as foundations and areas. As shown

in Figure 15.6, the project is subdivided into systems. The individual systems are further

divided into disciplines (e.g., civil, mechanical, electrical). The lowest level of the hierarchy

indicates physical end items (foundation 1, etc.). Work packages at this lowest level of the

hierarchy are called control accounts.

The rows of the matrix are defined by technology and responsibility. At the lowest level

of this hierarchy, the responsibilities are shown in terms of tasks, such as concrete, framing,

and earthwork. These tasks imply various craft specialties and technologies. Typical work

packages then are defined as concrete tasks on foundation 1 and earthwork on foundations

1 and 2.

This approach can be expanded to a three-dimensional matrix by considering the resources

to be used on each work package (see Fig. 15.7). Using this three-dimensional

breakdown, we can develop definition in terms of physical subelement, task, and responsibility,

as well as resource commitment. A cost code structure to reflect this matrix structure

is given in Figure 15.8. This 15-digit code defines units for collecting information in terms

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15.6 Cost Accounts for Integrated Project Management 259

Figure 15.6 Project control matrix.

of work package and resource type. Resource usage in terms of monetary units, quantities,

man-hours, and equipment-hours for a foundation in the boiler building would be collected

under work package code 121002. If this work relates to placement and vibration of concrete

by using a direct chute, the code is expanded to include the alphanumeric code DF441.

The resource code for the concrete is 2121. Therefore, the complete code for concrete in

the boiler building foundations placed by using a chute would be 121002-DF441-2121.

Figure 15.7 Three-dimensional visualization of work-package-oriented cost accounts.

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Figure 15.8 Basic cost code structure.

This code allows collection of cost data at a very fine level. Scheduling of this work is also

referenced to the work package code as shown in Figure 15.9. The schedule activities are

shown in this figure as subtasks related to the work package.

15.7 EARNED VALUE METHOD

One widely accepted way of calculating progress on complex projects using a work or

account based breakdownsystem is the Òearned valueÓ approach. This system of determining

project progress addresses both schedule status (e.g., on schedule, behind schedule, etc.)

and cost status (e.g., over budget, etc.). This method of tracking cost and schedule was

originally implemented by the Department of Defense in the late 1970s to help better

Figure 15.9 Project control matrix with scheduling of subtasks.

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15.7 Earned Value Method 261

control complex projects. The system was called the Cost and Schedule Control Systems

Criteria or C/SCSC. This method of monitoring contracts proved to be so effective that

other government agencies (e.g., Department of Energy, etc.) adopted C/SCSC as a means

of maintaining oversight on complex projects such as nuclear and conventional power plants.

Private owners such as power companies implemented similar systems since reporting to

various government authorities encouraged or required the use of C/SCSC and earned value

concepts. Ultimately, owners of complex industrial projects began to use the system as

well.

The idea of earned value is based upon a rigorous development of percent complete of

the budgeted costs associated with individual work packages or line items. Each work package

has an initial budget or estimate which is defined as the Budgeted Cost at Completion

or BCAC. As work proceeds on an individual work package or account, assessment of the

percent complete is made at various study dates. The initial schedule establishes an expected

level of work completion as of the study date. The level of expected production is often

shown as an S-Curve plotting the cost or units of production (e.g., units produced, work

hours expended, etc.) against time. This cost/production curve is referred to as the baseline.

At any given time (study date), the units of cost/production indicated by the baseline are

called the Budgeted Cost of Work Scheduled (BCWS).

The tracking system requires that field reports provide information about the Actual

Cost of Work Performed (ACWP) and the Actual Quantity of Work Performed (AQWP).

The Òearned valueÓ is the Budgeted Cost of Work Performed (BCWP). The relative values

for a given work package or account at a given point in time (see Fig. 15.10) provide

information about the status in terms of cost and schedule variance. The six parameters

which form the foundation of the Òearned valueÓ concept are:

BCWS: Budgeted Cost of Work Scheduled = ...

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