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Todays challenge of rapid technological advances and applica-tion of the Internet to many fields of engineering and con-struction encourages a shift in our planning paradigm. Thesame old way simply does not fit in this new open, fast-track

environment and our planning paradigm must shift from the currentunstructured and informal planning to a more structured and formalprocess. Research indicates that the key to project success is to invest

quality time in systematic planning in an early stage. Yet, we have reliedupon mostly unstructured and manual formation of plans. Existing sci-entific planning techniques (i.e., critical path method) are schedulingtools for analysis rather than plan generation. They manipulate data pro-vided by planners, not the knowledge used in generating project plans.

This paper introduces and explains the innovative concept of top-down back-to-front planning. The paper demonstrates the practicalapplication of this concept using several case studies. These case studiesillustrate how this new planning paradigm can influence planners to usea more formal approach, while keeping the big picture and projectobjectives in view throughout the planning process. The integration ofstate-of-the-art project controls software and Internet technology are atthe heart of this discussion.

Studies have identified a lack of industry standards as a major

obstacle in the construction industry adopting modern planning tech-niques. Several scheduling tools have been available for years and con-stantly enhanced, but little has been done in terms of developing a stan-dard approach to project planning. Current practices rely onunstructured and manual formation of plans. In fact, few planning toolsexist to aid the user to develop plans during the conceptual stage. Stud-ies indicate that despite the substantial developments in planning meth-ods and techniques, there is deep dissatisfaction with the current plan-ning practices [8, 12]. Traditional network-based tools using critical pathmethod (CPM) algorithms can help in analyzing a plan, but not in gen-erating it [6].

The conceptual phase of a project is the most critical stage wheremajor decisions take place that can affect the entire time and cost of aproject [7]. At this stage, the scope of work is not well defined and few

details are available. Gathering of information and data analysis todefine the scope and planning requirements are the most time-consum-ing activities.

The construction industry is crossing the threshold of a new era inthe communications revolution. The application of Internet technologyis rapidly advancing to many fields of engineering and construction.The Internet is revolutionizing the way the industry does business. BillGates, the founder of Microsoft said, The Internet has a huge potentialas it relates to construction. This is an industry that continually movesdetailed information back and forth between offices and remote jobsites. Pulling together even a simple straightforward project nowrequires the interaction of hundreds of people and thousands of docu-ments [13].

This fast-track climate encourages us to shift our planning para-digm from the current unstructured and informal planning to a morestructured and formal process that can use the advancing medium of theInternet.

This study presents a new approach to the process of planning witha top-down back-to-front planning method that is embedded in themodel that is discussed throughout this paper. This innovative and dis-

tinct approach will incite planners to use a structured approach to plan-ning while keeping the big picture and project objectives in viewthroughout the planning process. Although the model is formal in struc-ture, it provides great flexibility to planners to exercise judgment indeveloping specific conceptual plans. Planners will have the ability tocross over between intuitive and systematic approaches in developingconceptual plans quickly and more accurately when little project infor-mation is available.

This study emphasizes the potential of Internet technology andhow it can be used to facilitate the planning process and providedetailed planning information quickly and more accurately throughinteractive web communicators, video conferencing, reciprocatinge-mail, and the use of live or archived digital images of projects.

A total of 11 case studies of actual projects selected from two promi-

nent contracting firms, the Weitz Company of Des Moines, IA, andHCB Contractors of Dallas, TX, were analyzed in detail. The results ofthese case studies were published in research reports completed at IowaState University by the authors during 1996-1997 [15]. The paper isbased on the results of these case studies.

P&S.01

Top-Down Back-To-Front Project Planning

Dr. Faramarz Fred Rahbar and Dr. James E. Rowings Jr., PE CCE

Figure 1Top-Down Back-to-Front Planning

1998 AACE INTERNATIONAL TRANSACTIONS

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BACKGROUND

Planning Versus Scheduling-A Confusion Over TerminologyPlanning occupies a central position in the function of the project

manager, yet there is no consistent terminology covering the subject ofproject planning. The term planning has been subject of debates andcontroversy, which complicates our understanding of planning [10, 12].Furthermore, there seems to be a great confusion between the termsplanning and scheduling. Scheduling techniques are perceived as syn-onymous with project planning and sometimes with project manage-

ment as a whole [12, 1]. A clear indication of this problem is the confu-sion over job titles. Planners are sometimes referred to as schedulers,planning and scheduling engineers, cost and scheduling engineers,project control engineers, cost engineers, CPM schedulers, or schedul-ing analysts. The terms planning and scheduling are often used synony-mously. In fact, they are quite different, yet related [1].

Planning deals with what, how, and who. It is not scientific or sys-tematic.

Scheduling deals with when. It is fairly systematic and scientific.Just as there is a difference between planning and scheduling, there is


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Figure 2Top Down Back to Front Planning Navigation

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also a difference between planning and the plan. Planning is the processwhile the plan is a product of planning, or scheduling, or both [3]. Thescheduling process for a construction project is part of planning. Con-struction planning is the process of selecting the method and order ofwork from among various methods and possible sequences, while sched-uling is the determination of timing for those sequences and gives theoverall completion time [1]. Planning provides detailed information

and the basis for estimating time, as well as a baseline for project con-trol. The schedule is a reflection of the plan.

Planning PhilosophyProject managers go about planning largely based on their person-

al planning postures. Some managers prefer intuitive planning whileothers use detailed written plans. McKenny and Keen [11] suggestedtwo distinct and contrasting schools of thought or planning philoso-phies, the perceptive and receptive. In the perceptive approach, theplanner looks for a way to relate the data to existing mental concepts,patterns, or systems. Perceptive planners scan data in search of patterns;receptive planners are detail-oriented. Receptive planners are con-cerned with information and tend to withhold judgment until facts are

fully examined. McKenny and Keen also state that information is eval-uated in one of two ways: intuitively or systematically. Intuitive thinkersexamine data in an unstructured way, while systematic thinkers study itin a logical, organized manner. Therefore, how people think affects howthey plan. Perceptive and intuitive planners conduct informal, unstruc-tured planning and avoid formal approaches. Receptive and systematicplanners conduct planning on a logical procedural basis.

Dinsmore [3] discussed two conflicting planning approaches:behavior-oriented versus technocratic. The focus of the behavioralapproach is more on the planning process than planning product. Thebehavior-oriented approach is more intuitive, and planning is per-formed by those who are ultimately responsible for performing the work.The technocratic approach focuses on the plan itself. The plans are nor-mally prepared by planning experts who usually will not be performing

the work, and are then turned over to those responsible for plan imple-mentation. This is more systematic but less interactive.

Paradigm PitfallsPerceptive planners use an informal and unstructured approach

that focuses on the process rather than product. This is a bottom-upapproach where the planner starts at the detailed level and withholdsdecisions until the process is completed, facts are fully examined, andinformation becomes available. On the other hand, receptive plannersuse systematic approaches with the focus on the plan itself. This is atop-down approach. Most of the current planning practices, as con-

firmed by the participants in this research, are based on the bottom-upapproach. This means planners start with detail activities and summa-rize the outcome for management use. In the conceptual phase, whennot too much detail is available, planners are forced to make assump-tions or wait until more information becomes available. In short, theplans integrity and timing can be affected. The top-down approach isnot without flaws either. This method, mostly used by scheduling con-sultants, may lead to simplistic solutions that leave out pertinent details.Besides, there is always the hazard of alienating the planner from those

who actually implement the plan. In either case, managers may befocusing on getting the activities right without the right activity. Gettingthe activities right is efficiency. Getting the right activity is effectiveness.The most effective plans are produced when these two apparent con-flicting approaches are used in a way to complement each other.

NEED FOR A CPM SUPPLEMENT

CPM and project network scheduling made a significant contribu-tion to planning and the successful completion of construction projects;CPM has continually evolved since its development in the late 1950s.However, a serious issue under emphasized by the planning professionand not addressed at all by the software companies is how to go about

preparing the required input for the CPM model. Traditionally, plan-ners rush to develop project schedules based on past experience andintuition, usually developed in a crisis mode, with little time to analyzethe plan prior to its execution. Little thought is given to the roles of theowner, architect, contractors, material suppliers, and other partiesinvolved. These parties each have different contractual terms withnumerous and conflicting objectives.

The basis for a good plan is a good description of the scope of work.Project scope forms the baseline for control. If the scope is not welldefined, it is difficult to accurately define material and work require-ments, and determine the quantity of work, staffing, and other resourcerequirements. CPM is not the tool for identifying and formalizing proj-


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Figure 3User Identifies Project Type and Components

Figure 4Interactive Project Front Page (IPFP)

Figure 5Each PWBS Level Is Entered as a Line Item

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ect scope of work, contractual and other commitments, long-lead items,and materials requirements. These are fundamentally real planningissues. The CPM technique assumes that a planner has alreadyaddressed these issues prior to input. The results of this hit and missapproach are CPM schedules that are not reflective of the full projectscope and objectives, client requirements, contract milestones, etc., andprovide very little information as far as schedule basis, qualifications,and assumptions. A schedule that is inaccurate or does not demonstratethe intended project plan will most likely be a detriment to the proj-ect time [1]. The problem is not the CPM technique, but what is input

into the CPM. Garbage-in garbage out is the expression commonlyused.Project planning can be improved by focusing on the planning

process rather than only on the planning technique [9]. Extensive timeis taken by reviewing, learning, and struggling with new schedulingtechniques and computer software, but very few have addressed theplanning process and what must be done to improve it [10].

PLANNING PROCESS AND THE INFORMATION AGE

Planning is the means, not the end. The process of planning is asimportant as the plan itself. Dynamic interaction, brainstorming, andjudgment exercises among the project participants are essential duringthis process. A lack of integration among contractual parties and lack ofinvolvement of line supervisors will lead to plans being ignored or mis-interpreted. The quality of the information is a function of a thoroughproject organization plan, data collection, and project analysis.

Collecting information and making decisions regarding this infor-mation is the core of planning. The project manager is the nerve centerin the midst of this process. Information gathering is time consumingand requires considerable resources. This includes an informationsearch, analysis, processing of data, evaluation of alternatives, and deci-sion-making. Data are collected face to face or one on one, throughmeetings or by correspondence (mail, telephone, fax, etc.). However,the majority of information is prepared using the planners or projectmanagers past experience on similar projects [10]. There is no formulafor cranking out a project plan. Planning is much more than developinga network logic and assigning durations and sequences of work. Animportant part of this process is the interaction and brainstormingamong the project team and other entities involved. Teamwork and


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Figure 6Establish major/interim milestone dates

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communication are critical to the success of the planning process. Forpre-project planning to be successful, team continuity is needed, andthe team must be cultured through team building and open communi-cation [4]. The process contributes to the understanding of the projectteam regarding their project, the goals and objectives, the scope of work,and how they can work together cohesively to meet the objectives. Plan-ners need a system that facilitates this process but doesnt replace it.

The information revolution is transforming the nature of theeconomy and the nature of our work in many fields, including engi-neering and construction. Among the most dramatic implications of this

revolution to the field of project planning is overcoming the sense ofremoteness. Massive information resources are becoming available toalmost anyone, almost anywhere, almost anytime. Communicationcompanies are already laying thousands of miles of fiber-optic lines toenhance this process and increase accessibility. The technology willallow electronic documents to be indexed and retrieved using interac-tive exploration. Video-conferencing has already started and willbecome common in most businesses. The use of video conferencingand the Internet are now making it possible for those with high-techskills to work for companies far away. This will make collaboration andcoordination easy among the project team. Team members can com-municate across the globe as if they were in the same building.

The rapid expansion of the Internet and its application to ourindustry requires a re-examination of the planning process. Many

changes must take place in order to apply state-of-the-art technology.The process must shift toward a systematic and standard operationincluding the use of common work breakdown structures, standardmilestones, typical activities, and generic logic. The role of the plannermust also change to more of a facilitator inciting expert opinions ratherthan playing the role of the expert. The best planner will be the one whoknows how and where to find, how to interpret, and skillfully applyinformation. The main focus must be both on the process as well asproduct. In this new paradigm, many questions will be raised, such as:

Where is the human touch? Will social skills be neglected by individu-als locked for hours to their private terminals? What will happen to theintuitive and creative thinking required during the planning process?

What will happen to those who resist the new technology? What will bethe role of consultants in this process? Is it necessary for planners to

work from their offices?

TOP-DOWN BACK-TO-FRONT PLANNING APPROACH

The innovative concept of top-down back-to-front planning is themechanism by which planners can be guided in applying an interactiveplanning process while employing Internet technology. This distinctmethod provides planners with the ability to cross over between intuitiveand systematic planning by focusing on both the planning process andthe planning product. Detailing a project breakdown structure, mile-stones, and durations, key restraints, etc., is systematic in nature and canbe easily captured from past project data, while activity sequencing,

integration of resources, overall approaches, and the application of softlogic are more abstract and require intuitive and creative thinking. Thecross-over between these is a series of decision points that requires aplanners judgment to determine the cross-over point.

Using this approach, the planner is at the top of the project in aproactive mode to start with project objectives and breakdown of theproject and milestones to meet the contractual dates and deadlines (fig-ure 1). When detailed information is not available in a particular area,activities are kept at a summary level with a strategy to find out the causeof the lack of information and how and when more details will be avail-able. The level of detail that is recommended for the initial planning iswhat can be referred to as the control level. This is a step further thana milestone or summary schedule but not as detailed as schedules usedin the field. The concept of top-down back-to-front planning can be eas-

ily applied in four phases using a few simple steps. Figure 2 is anoverview of how a planner can navigate through the process using top-down back-to-front planning. The steps that follow were developedusing results of case studies involving several retirement communitiesand health center projects.

Phase I: Project DefinitionStep 1: The user initiates the type of project and identifies the proj-

ect components. This is done through an icon-based, menu-drivenscreen similar to the prototype of figure 3. The pictorial format facili-tates user interaction with a minimum amount of input on the part ofthe user. A library of various icons for different types of facilities andcomponents are kept in a database and are retrieved based on what pre-

vious icon is clicked by the user. The end result of this step is the ini-


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Figure 7Establish Key Restraints

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tiation of a totally interactive webpage henceforth referred to as theinteractive project front page (IPFP), similar to that of figure 4. IPFPwill allow the planner and other team members to post information andcreate links within and outside the project with hyperlinks to otherwebpages and files stored in various locations. For example, when theuser clicks on the scope of work, it is linked to an explicit scope of workdocument that describes the project in great details. User interactionthrough IPFP is at the heart of the system.

Step 2: user enters basic project data using the IPFP established inthe first step. A user dialogue box facilitates user input to capture as

much information as possible regarding the new project. This includessuch information as the project title, location, owner, construction man-ager, developer, architect, total project cost, allocated project duration,project start date, contract completion date, and other pertinent data.

Step 3: a list of predefined project components, milestones, and rel-evant parameters from similar projects is automatically retrieved basedon the data entered on IPFP. The users are free to examine this infor-mation and modify it. By having this table predefined and enteredbeforehand, the user will only need to scroll through this list via aninteractive dialogue box.

Phase II: Project Work Breakdown StructureStep 4: once the project is defined and initiated, the planner starts

from the top down to develop the project work breakdown structure,which is the top-down logical structuring of project work that definesand displays all of the work to be done in accomplishing the projectobjectives defined in steps one and two [5].

The PWBS is developed by dividing the project into discrete andlogical tasks using an outline structure [2]. It partitions the project intomanageable elements of work for which costs, budgets, and schedulescan be established. The integration of a projects organization structurewith the PWBS helps the project manager to assign responsibility forvarious technical tasks to specific project personnel [14]. The PWBS isstructured in levels of work detail, beginning with the final product, andthen separated into identifiable work elements. It can be prepared bystarting from the top level (project level), and defining all the majorcomponents to support the top level. Next, the user defines all the

subcomponents to support level two. The user continues this processuntil all major PWBS elements leading to a specific deliverable aredefined.

The PWBS is the heart of any project integration effort. Projectmanagers use it to ensure that all tasks are identified and fit togetherproperly to complete the project [2]. Under the top-down back-to-frontmethod, a planner is guided in developing the PWBS by examiningcommon work breakdown structures retrieved from a library of similarprojects while customizing it to fit the requirements of the project athand. Each PWBS element becomes a summary activity and shown asa line item on the state-of-the-art CPM scheduling program as illustrat-ed in figure 5.

Phase III: Project Milestones and Key RestraintsStep 5: once the PWBS is developed, the planner starts from the

back-to-front with the contractual milestones and important deadlines.These milestones are usually different for each type of project and varyeven from project to project. It is best to start with the last contract com-pletion date, which may be the tenant occupancy date, start-up andcommissioning date, turbine roll, revenue date, etc., depending on theproject. These dates are marked as a milestone on the time-scale sched-ule along with the PWBS. Next, intermediate milestone dates are iden-tified and marked on the same schedule. These dates, which also varyfrom project to project, may include such milestones as substantialcompletion and punch list dates for each area or facility, building enclo-sure dates, traffic or area reinstatement dates, design freeze date, engi-

neering release dates, issue for review or construction dates, turnover tooperations/start-up dates, etc. Many of these dates relate directly to thePWBS line items already defined in step 4 and are shown on the sameline in time-scale format, as illustrated in figure 6.

Step 6: after all the contractual and significant milestones aredefined and entered, the planner enters key restraints. Examplesinclude long-lead material and equipment procurements, financing andlegal decisions, licensing and permits, design reviews, and clientapprovals. These activities are not locked in time, but affect the timingof other activities, and many are potentially critical. Although the plan-

ner cannot show these as milestones, typical duration cycles for theseactivities are known based on the information obtained from past pro-jects or the latest data available from the vendors, engineers, sub-con-tractors, and other parties. The Internet plays an important role in facil-itating and obtaining the prevailing information.

Phase IV: Project Control LevelStep 7: steps 1 to 6 set the framework for the planner to develop a

working plan. The last step is to add all the bits and pieces of details tocomplete the process. The planner, much like an artist, has her canvasand materials in hand and can now be guided and apply creativity todevelop the required detail activities for each summary line items. TheInternet can enhance this process by providing typical activities and

sequences for each line item of the PWBS. The planner also has theopportunity to review a multimedia library of past project pictures andfilms to graphically visualize this process and improve upon it. Many ofthe strengths and weaknesses of past projects, sequences, and methodsof construction come to the surface, thus complementing the planningprocess. At any point during this process, the user has the option to over-ride the activities, and sequences to custom fit the details for the projectat hand.

This paper presented a practical application of top-down back-to-front planning. It demonstrated that by applying a few sim-ple steps, planners can be encouraged to use a structuredapproach in plan formation and exploit the enormous

resources freely accessible through the Internet. Using this approach,the planner is at the heart of the system, allowing great flexibility to exer-cise judgment and intuition. This will allow the planner to be on top ofthe project in a proactive mode to start with project objectives and breakdown the project milestones to meet the contractual dates and dead-lines. The system provides systematic analysis when dealing with quan-titative variables such as project work breakdowns, milestones, activities,durations, and generic logic. On the other hand, planners have theopportunity to apply judgment, intuition, and creativity at various deci-sion points during this process in a proactive role. The level of detail rec-ommended for the initial planning is at the planners control. User inter-action is one of the prominent features of the system. Redundant androutine data collection, input, calculations, etc., are carried out auto-matically, while several decision points were built-in the system thatrequires user participation, enforcing more creative input on the part ofthe user.

There is no doubt that the latest technology and the Internet canpositively contribute to facilitating the gathering of information andplanning input that is required from numerous parties who are normal-ly situated distances apart. However, the question of data security, con-fidentiality, and the size and quality of graphics and captured images areissues that must be addressed in the future. Internet technology is stillevolving; however, the use and the integration of the above conceptsand techniques to visually simulate construction planning at the con-ceptual stage of a project is promising.


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Dr. Faramarz Fred RahbarBechtel

191 Messogion Ave.115 25 Athens, Greece

Dr. James E. Rowings Jr., PE CCEIowa State University

456 Town EngineeringAmes, IA 50014


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