Metode Network Planning

1. Metode Penjadwalan dengan Metode Network Planning

Network Planning diperkenalkan pada tahun 1950-an oleh tim perusahaan Du Pont dan Rand Corporation untuk mengembangkan system control manajemen. Metode ini dikembangkan untuk mengendalikan sejumlah besar kegiatan yang memiliki ketergantungan yang kompleks. Metode ini relative lebih sulit, hubungan antar kegiatan jelas dan dapat memperlihatkan kegiatan kritis. Dari informasi Network Planninglah monitoring serta tindakan koreksi kemudian dapat dilakukan, yakni dengan memperbaharui Jadwal. Akan tetapi, metode ini perlu dikombinasikan dengan metode lainnya agar lebih informative dan jelas.

1.1 Tahapan penyusunan Network Planning adalah:

1. Melakukan inventarisasi kegiatan- kegiatan dari paket WBS berdasarkan pada item-item pekerjaan, lalu diberi kode-kode kegiatan untuk memudahkan identifikasi.
2. Melakukan perkiraan durasi untuk setiap kegiatan dengan mempertimbangkan jenis pekerjaan, volume pekerjaan, jumlah sumber daya, lingkungan kerja, serta produktivitas pekerja.
3. Penentuan logika ketergantungan antar kegiatan dilakukan dengan tiga kemungkinan hubungan, yaitu kegiatan yang mendahului (predecessor) dan kegiatan yang sesudahnya (successor) serta bebas.
4. Perhitungan analisis waktu serta alokasi sumber daya, dilakukan setelah langkah-langkah di atas dilakukan dengan akurat dan teliti.

1.2 Manfaat daripada penerapan Network Planning adalah:

1. Penggambaran logika hubungan antar kegiatan, membuat perencanaan proyek menjadi lebih terinci dan lebih detail.
2. Dengan memperhitungkan dan mengetahui waktu terjadinya setiap kegiatan/kejadian yang ditimbulkan oleh satu atau beberapa kegiatan, kesukaran-kesukaran yang bakal timbul dapat diketahui jauh sebelum terjadi, sehingga tindakan pencegahan yang diperlukan dapat dilakukan.
3. Dalam Network Planning dapat terlihat sangat jelas waktu penyelesaian yang ditunda atau harus disegerakan.
4. Membantu dalam komunikasi hasil Network Planning yang ditampilkan.
5. Memungkinkan dicapainya hasil proyek yang lebih ekonomis dari segi biaya langsung (Diret Cost) serta penggunaan sumber daya.
6. Berguna untuk menyelesaikan klaim yang diakibatkan oleh keterlambatan dalam menentukan pembayaran  kemajuan pekerjaan, melakukan analysis Cashflow dan Pengendalian Biaya.
7. Menyediakan kemampuan analisis untuk mencoba melakukan perubahan sebagian dari proses, lalu melakukan pengamatan dari efek terhadap proyek secara keseluruhan.
8. Terdiri atas Metode Activity On Arrow dan Activity On Node atau biasa disebut dengan PDM (Precende Diagram Method).

 Activity On Arrow Diagram (AOA)

Gambar 1.0 Diagram AOA

1.3 Metode ini memiliki karakteristik sebagai berikut:

1.   Diagram Network dibuat dengan menggunakan anak panah untuk menggambarkan kegiatan dan Node-nya menggambarkan peristiwa/event. Node pada permulaan anak panah ditentukan sebagai I-Node, sedangkan pada akhir anak panah ditentukan sebagai J-Node, hubungan keterkaitannya adalah Finish to Start
2. Menggunakan perhitungan maju (forward pass) untuk memperoleh waktu mulai paling awal (EETi=Earliest Event Time Node-i) pada I-Node dan waktu mulai paling awal (EETj= Earliest Event Time Node j) pada Node J dari seluruh kegiatan, dengan mengambil nilai maksimumnya, begitu juga dengan nilai seperti dibawah ini:

a.      ES (Earliest Start) : Saat paling cepat untuk mulai kegiatan

b.      EF (Ealiest Finish): Saat paling cepat untuk akhir kegiatan

    3. Menggunakan perhitungan mundur (backward pass) untuk memperoleh waktu selesai paling  lambat (LETi= Latest Event Time node i) pada I node dan waktu selesai paling lambat (LETj = Latest Event Time node j) pada J node dari seluruh kegiatan, dengan mengambil nilai minimumnya,   begitu juga dengan nilai dibawah ini:
          a. LF (Latest Finish): Saat paling lambat untuk akhir kegiatan
          b. LS (Latest Start) : Saat paling lambat untuk mulai pekerjaan

    4.  Diantara 2 peristiwa tidak boleh ada dalam 2 kegiatan, sehingga untuk  menghindarinya digunakan kegiatan semu atau Dummy yang tidak mempunyai durasi.

     5.  Menggunakan CPM (Critical Path Method) atau Metode Lintasan Kritis, dimana pendekatan yang      dilakukan hanya menggunakan satu jenis durasi pada kegiatannya. Lintasan Kritis adalah Lintasan       dengan kumpulan kegiatannya yang memiliki TF (Total Float) = 0

    6. Float adalah batas toleransi keterlambatan suatu kegiatan yang dapat dimanfaatkan untuk otimalisasi waktu dan alokasi sumber daya.

1.4 Jenis-jenis Float adalah:

         1.      TF (Total Float)

a.      Waktu tenggang maksimum dimana suatu kegiatan boleh terlambat tanpa menunda waktu penyelesain proyek.

b.      Hal ini sangat menentukan lintasan kritis untuk mempercepat durasi proyek, bila nilai TF=0

c.      TFij=LETj-EETi – Durasi ij (Event oriented)

         2.  FF (Free Float)

a.      Waktu tenggang yang diperoleh dari saat paling awal peristiwa j dan saat paling awal peristiwa i dengan selesainya kegiatan tersebut

b.      Sanagt bermanfaat untuk alokasi sumber daya dan waktu dengan memindahkannya ke kegiatan lainnya ke kegiatan lain.

          3. IF (Independent Float)

a.   Waktu tenggang yang diperoleh dari saat paling awal peristiwa j dan saat paling lambat peristiwa j dengan selesainya kegiatan tersebut

b.    IFij = EETj – LETi - Durasi ij

Determine Budget

1. Determine Project Budget

This process of aggregating the estimated costs of individual activities or work packages to establish an authorization cost baseline. This baseline includes all authorized budgets, but excludes management reserves.

The inputs, tools, techniques, and outputs of this process are describes below.

1.1 Determine Budget: Inputs 

The most important inputs to this process are the estimates determined in the previous process which is Cost Estimates. Other important inputs come from other knowledge areas such as Scope, Time, Human Resource, Risk and Procurement. This process requires the following inputs:

1.1.1 Cost Management Plan

This plan describes how the project costs will be managed and controlled

1.1.2 Scope Baseline
As described in the previous process which is Cost estimates, the scope baseline is a component of the project management plan and includes the product descriptions, acceptance criteria, key deliverables, project boundaries, assumptions, and constraints about the project.

It may also include requirements with contractual and legal implications for health, safety,security, performance, environmental, insurance, intellectual property rights, licenses and permits.

1.1.3 Activity Cost Estimates

These are outputs from the previous process which is Cost estimates

1.1.4 Basis of Estimates

Supporting detail for cost estimates should be specified as describes above. Any basic assumptions dealing with the inclusion or exclusion of indirect costs in the project budget are specified in the basis of estimates.

1.1.5 Project Schedule

As described in the previous process which is cost estimates, the project schedule includes a planned start date and planned finish date for each activity as well the resources required This information can be used to aggregate costs to the calendar period in which the costs are planned to be incurred.

1.1.6 Resource Calendars

These provide information on which resources are assigned to the project and when they are assigned. This information can be used to indicate resource costs over the duration of the project.

1.1.7 Risk Register

This is an output of process Identify Risks and is used to aggregate costs for risk responses to obtain the contingency reserves for the project.

1.1.8 Agreements

This is an output of procurement management process and applicable contract information and costs relating to products, services, or results that have been purchased are included when determining the budget.

1.1.9 Organizational Process Assets

These are the processes or process related assets that can be used in this process including: Existing formal and informal cost budgeting related to policies, procedures and guidelines as well as cost budgeting tools and reporting methods.

1.2 Determine Budget: Tools and Techniques 

There are five tools and techniques that can be used:

1.2.1 Cost Aggregation

Cost estimates are aggregated by work packages in accordance with the W.B.S. The work package cost estimates are then aggregated for the higher components levels of the W.B.S (such as control accounts) and ultimately for the entire project.

1.2.2 Reserves Analysis

This can be establish both the contingency reserves and the management reserves for the project.

1. Contingency reserves are allowance for unplanned but potentially required changes that can results from realized risks identified in the risk register.
2. Management reserves are budgets reserved for unplanned changes to project scope and cost.

1.2.3 Expert Judgment

This expertise is provided by any group or individual with specialized knowledge or training and is available from many resources, including: other units within the organization, consultants, stakeholders, including customers or sponsors, professional and technical associations, industry groups, subject matter experts, and project management office (P.M.O).

1.2.4 Historical Relationships

This refer to using historical data from other projects in which costs are known for the same or similar activities.

1.2.5 Funding Limit Reconciliation

The expenditures of funds should be reconciled with any funding limits on the commitment of funds for the project. A variance between the funding limits and the planned expenditures will sometimes mean rescheduling the work to level out the rate of expenditures. This can be accomplished by placing imposed date constraints for work into the project schedule.

Cost aggregation of the work packages produces the cost estimate of the project. Adding the cost of risk responses and contingency reserves produces the cost baseline. Adding the management reserves, which are not controlled by the project manager but by management, to the cost baseline, provides the cost budget. If the funding for the whole project is incremental, then care must be taken to ensure that the project does not run out of money as a result of getting too far ahead of the schedule.

1.3 Determine Budget: Outputs 

This process will create the following outputs:

1.3.1 Cost Performance Baseline

This specifies what costs will be incurred and when. This matters because most projects will not receive their funding as a lump sum at the beginning but will be financed according to a monthly or quarterly budget. This means that the project manager will need to indicate when funds need to be available.

The simplest way to produce a cost baseline would be to aggregate all of the anticipated costs of the project and assume that they would be needed in proportion to the planned timescale.

For example:

Project Total cost was $ 100,000
Project Planned to take 20 weeks

Then a simple cost graph could be produced with the vertical axis calibrated in dollars and the horizontal axis calibrated in weeks.

You could produce a simple cost graph by assuming that the planned cost per day was linear, that is as a straight line coming from the origin to a point that is aligned to $ 100,000 on the vertical axis and 20 weeks on the horizontal axis as shown:

We have just created the cost performance baseline for that project as it takes the estimated project expenditures and align them with dates on the Calendar. This allows the organization to plan for cash flow and to make suitable arrangements in advance so that the funds are available when needed and not before.

This might be accurate enough for a very simple project where both the labor and material costs were fairly constant from day to day. But for projects with any degree of complexity it is necessary to produce separate cost baselines for different categories of expenditure, such as human resources at different labor rates, plant, materials and other equipment.

For this reason the cost performance baseline may consist of several sub baselines, which can be aggregated to produce totals. In most projects the rate of expenditures is not linear but follows an "S" shaped curve as shown.

The reason for this is that the rate of spent at the beginning and end of the project is typically lower than that during the execution phase.

1.3.2 Project Funding Requirements

        These are derived from the cost baseline described above and need to reflect the cash flow needs of the project including management reserves and contingencies. They are an important output, because they may require the project schedule to be adjusted to the necessities of the periodic project funding requirements.

1.3.3 Project Document Updates

      This include the activity cost estimates, risk register and project schedule

Penjadwalan Proyek - In Bahasa Indonesia

1. Pendahuluan

    Penjadwalan proyek merupakan salah satu elemen hasil perencanaan, yang dapat memberikan sebuah informasi tentang jadwal rencana dan kemajuan proyek dalam hal kinerja sumber daya berupa biaya, tenaga kerja, peralatan dan material serta rencana durasi proyek dan progress waktu dalam penyelesaian proyek. Di dalam proses penjadwalan, penyusunan kegiatan dan hubungan antar kegiatan dibuat lebih terperinci dan sangat detail.

      Hal ini dimaksudkan untuk membantu pelaksanaan evaluasi proyek. Penjadwalan atau scheduling adalah proses pengalokasian waktu yang tersedia untuk melaksanakan masing-masing pekerjaan dalam rangka menyelesaikan suatu proyek hingga tercapainya hasil optimal dengan mempertimbangkan keterbatasan-keterbatasan yang ada.

   Selama proses pengendalian proyek, penjadwalan mengikuti perkembangan proyek dengan berbagai persoalannya. Proses monitoring serta updating selalu dilakukan untuk mendapatkan penjadwalan yang paling realistis agar alokasi sumber daya dan penetapan durasinya sesuai dengan sasaran dan tujuan dari proyek itu sendiri.

Secara umum penjadwalan mempunyai beberapa manfaat seperti berikut ini:

1. Memberikan pedoman terhadap unit pekerjaan/kegiatan mengenai batasan waktu untuk dimulainya dan diakhirinya proyek.
2. Memberikan sarana bagi manajemen untuk melakukan koordinasi secara sistematis dan realistis dalam penentuan alokasi prioritas terhadap sumber daya yang ada.
3. Memberikan sarana untuk melakukan penilaian kemajuan pekerjaan.
4. Menghindari pemakaian sumber daya yang berlebihan, dengan harapan proyek dapat diselesaikan tepat waktu atau lebih cepat dari waktu yang telah ditetapkan.
5. Memberikan kepastian waktu pelaksanaan dan penyelesaian pekerjaan dalam proyek
6. Merupakan sarana yang sangat penting dalam pengendalian proyek.

Kompleksitas penjadwalan  proyek sangatlah dipengaruhi oleh beberapa faktor sebagai berikut:

1. Sasaran dan tujuan proyek itu sendiri
2. Keterkaitan dengan proyek lain agar dapat terintegrasi dengan Master Schedule proyek.
3. Dana yang dibutuhkan serta dana yang tersedia
4. Waktu yang dibutuhkan, waktu yang tersedia serta prakiraan waktu yang hilang dan hari-hari libur yang telah ditetapkan oleh pemerintah.
5. Susunan dan jumlah kegiatan proyek proyek serta keterkaitannya.
6. Waktu untuk kerja lembur dan pembagian shift kerja yang dibutuhkan untuk mempercepat proyek.
7. Keahlian para tenaga ahli serta kecepatan dalam pengerjaannya.

2. Metode Penjadwalan Proyek

   Ada beberapa metode penjadwalan proyek yang digunakan untuk mengelola waktu dan sumber daya proyek. Masing-masing metode mempunyai kelebihan dan kekurangan. Pertimbangan penggunaan metode-metode tersebut didasarkan atas kebutuhan dan hasil yang di inginkan. Kinerja waktu akan berimplikasi terhadap kinerja biaya, sekaligus kinerja proyek secara keseluruhan. Oleh karenanya variabel-variabel yang mempengaruhinya juga harus di monitor secara ketat. Apabila terjadi penyimpangan terhadap rencana semula, maka segera dilakukan evaluasi dan tindakan koreksi agar proyek tetap pada kondisi yang di inginkan.

3. Waktu dan durasi pekerjaan

    Dalam konteks penjadwalan, terdapat dua perbedaan, yaitu waktu dan kurun waktu (durasi). Bila waktu menyatakan siang/malam, sedangkan durasi menunjukkan lamanya waktu yang dibutuhkan  dalam menyelesaikan suatu aktivitas/kegiatan, seperti lamanya kerja dalam satu hari adalah 8 jam. Menentukan durasi suatu kegiatan biasanya dilandasi oleh Volume Pekerjaan dan Produktifitas kelompok kerja/crew yang ada dalam menyelesaikan suatu pekerjaan.

Produktifitas dapat diperoleh dari pengalaman suatu perusahaan dalam bentuk Basis data/data base. Sebagai contoh kemampuan crew dalam menyelesaikan pekerjaan dinding bata rata-rata adalah 10 m2/hari, maka produktifitas crew tersebut adalahg 10 m2/hari, sedangkan Volume Pekerjaan dinding bata 240 m2.

Maka:

Durasi pekerjaan dinding bata = Volume pekerjaan / produktifitas crew

                                                 = 240 m2/hari / 10m2/hari

                                                 = 24 hari

4. Bagan Balok / Bar Chart / Gantt Chart

  Bar Chartt ditemukan oleh Henry L Gantt dan Frederick W Taylor dalam bentuk bagan balok, dengan panjang balok yang menyatakan lamanya suatu pekerjaan. Format bagian baloknya dibuat sangat informatif, mudah dibaca dan efektif untuk komunikasi serta dapat dibuat mudah dan sederhana.

Bagan balok terdiri atas sumbu Y yang menyatakan kegiatan atau pekerjaan sedangkan sumbu X menyatakan satuan waktu dalam hari, minggu atau bulan.

Pada bagan ini juga dapat ditentukan milestone atau baseline sebagai bagian target yang harus diperhatikan guna kelancaran proyek.

5. Kurva S (S-curve) atau Hannum Curve

    Kurva S adalah grafik yang dikembangkan oleh Warren T Hannum atas dasar pengamatan terhadap sejumlah proyek sejak awal hingga akhir proyek.

  Kurva S dapat menunjukkan kemajuan proyek sejak awal hingga akhir proyek. Kurva S menunjukkan kemajuan suatu proyek berdasarkan pada kegiatan, waktu dan bobot pekerjaan yang di representasikan sebagai persentase kumulatif dari seluruh proyek. Visualisasi Kurva-S dapat memberikan informasi mengenai kemajuan proyek dengan membandingkan terhadap jadwal rencana.

Bar Chart ( Bagan balok) - in Bahasa Indonesia

      Sekarang saya akan membahas perihal penjadwalan dengan metode bagan Balok atau yang biasa kita kenal sebagai Bar Chart atau GANTT Chart.

1. Pengertian Bar chart / GANTT Chart
    Dalam dunia konstruksi, teknik penjadwalan yang paling sering digunakan adalag Bar Chart atau Bagan Balok. Bar chart adalah sekumpulan aktivitas yang ditempatkan dalam kolom Vertikal, sementara waktu ditempatkan dalam baris horizontal. Waktu mulai dan selesai setiap kegiatan beserta durasinya ditunjukkan dengan menempatkan balok horizontal di bagian sebelah kanan dari setiap aktivitas.
Perkiraan waktu mulai dan selesai dapat ditentukan dari skala waktu horizontal pada bagian atas bagan. Panjang dari balok menunjukkan durasi dari aktivitas dan biasanya aktivitas-aktivitas tersebut disusun berdasarkan kronologi pekerjaannya.

     Bar Chart ini dibuat pertama kali oleh Henry.L. Gantt pada masa perang dunia pertama, sehingga sering juga disebut sebagai Gantt Chart. Bar Chart atau Gantt Chart digunakan secara luas sebagai teknik penjadwalan dalam bidang konstruksi. Hal ini karena Gantt chart memiliki ciri-ciri sebagai berikut:

1. Mudah dalam pembuatannya
2. Memiliki bentuk yang mudah dimengerti
3. Bila digabungkan dengan metode lain, seperti Kurva S dapat dipakai lebih jauh sebagai pengendalian biaya

Meskipun memiliki beberapa keuntungan, penggunaan metode Bagan Balok terbatas karena memiliki kendala-kendala berikut:

• Tidak dapat menunjukkan secara spesifik hubungan ketergantungan antara satu dengan lainnya antara satu kejadian dengan kejadian lainnya, sehingga sangat sulit untuk dapat mengetahui dampak yang diakibatkan oleh keterlambatan satu kegiatan terhadap jadwal keseluruhan proyek.
• Sulit dalam mengadakan perbaikan atau pembaharuan, karena umumnya harus membuat bagab balok yang baru.
• Untuk proyek berukuran sedang dan besar, lebih-lebih yang bersifat kompleks, penggunaan bagan balok akan menghadapai kesulitan

2. Cara Membuat Bar Chart / Gantt Chart

     Pengunaan Bar Chart bertujuan untuk mengidentifikasi unsur waktu dan urutan dalam merencanakan suatu kegiatan, terdiri dari waktu mulai, waktu selesai dan pada saat pelaporan. Penggambaran bar Chart terdiri atas Kolom dan Baris. Pada kolom tersusun urutan kegiatan  yang disusun secara berurutan, sedangkan baris menunjukkan periode waktu yang dapat berupa hari, minggu ataupun bulan. (Lihat Figure 1.0).

Perincian yang terdapat dalam Bar Chart adalah:

• Pada sumbu horizontal X tertulis satuan waktu, misalnya hari, minggu, bulan, tahun. Waktu mulai dan akhir suatu kegiatan tergambar dengan ujung kiri dan kanan balok dari kegiatan yang bersangkutan.
• Pada sumbu vertikal Y dicantumkan kegiatan atau aktivitas proyek dan digambarkan sebagai balok.
• Perlu diperhatikan urutan kegiatan atau aktivitas proyek  antara satu dengan yang lainnya. 

Cost Control in Project

         Once the project starts, it's necessary to keep track of actual cost and committed cost so they can be compared to the CBC (Cumulative Budget Cost).

1. Actual Cost

    To keep track of actual cost on a project, it's necessary to set up a system to collect, on a regular and timely basis, data on funds actually expended. Such a system might include procedures and forms for gathering data. An accounting structure should be established based on the work breakdown structure numbering system so that each item of actual cost can be charged to the appropriate  work package. Each work package's actual cost can then be totaled and compared to it's CBC.

     Weekly time sheets are often used to collect actual labor costs. Individuals working on the project indicate the numbers of the work package on which they worked and the number of hours they spent of each work package.

    These hours are hours are then multiplied by the hourly cost rate for each individual to determine the actual dollar cost. In companies using a matrix organization structure, individuals may be assigned to several project concurrently. In such cases, the individual has to indicate the proper project number as well as the work package number on the time sheet to ensure that the actual labor costs are charger to the appropriate project. When invoices are received for materials or services that were purchased for use on the project, they, too have to be charged to the proper work package number.

2. Committed Cost

    In many projects, large dollar amounts are expended for materials or services that are used over a period longer than one cost reporting period. These committed costs need to be treated in a special way so that the system periodically assigns a portion of their total cost to actual cost, rather than waiting until the materials or services are finished to charge to the total actual costs.

    Committed costs are also known as commitments or encumbered costs. Costs are committed when an item (material, subcontractor) is ordered, usually by means of a purchase order, even though actual payment may take place at some later time when the material or service has been completed,  delivered, and invoiced. When a purchase order are committed and are no longer available to be spent on other project activities. The committed amount must be considered as encumbered, or set aside, because funds will be needed to pay the supplier or subcontractor at some time in the future, when the material or service is delivered and an invoice is received.

For example, if you hire a Contractor to paint your home for $ 5,000, you have committed $ 5,000, even though you may not actually pay the Contractor until the work is finished.
     To permit a realistic comparison of actual cost to cumulative budgeted cost, portions of the committed should be assigned to actual cost while the work being performed. In some case, the supplier or subcontractor may require progress payments, rather than waiting until all the work is finished before paid. In such situation, when an invoice is received from the supplier or subcontractor for a partial progress payment, the amount of that invoice should be charged to the actual cost for the proper work package.


3. Comparing Actual Cost to Budgeted Cost

     As data are collected on actual cost, including portions of any committed cost, they need to be totaled by work packages so that they can be compared to the cumulative budgeted cost.
Figure 1.0 shows actual cost by time period for each work package through week 8 (Packaging machine project). Also shown is the period by period actual cost for the entire project, as well as the cumulative actual cost (C.A.C).

Figure 1.0 indicates that at the end of week 8, $ 68,000 has actually been expended on this project. The CBC in Figure 4.0 reveals that only $ 64,000 was budgeted to have spent by the end of week 8. There is a Variance of the $ 4,000 the project is over running its Budget.

Project Budgeting

            The Project budgeting process involves two steps. First, the project cost estimate is allocated to the various work packages in the project work breakdown structure. Second, the budget for each  work package is distributed  over the duration of the work package so that's possible to determine how much of its budget should have been spent at any point in time.

1. Allocating the Total Budgeted Cost
Allocating total project costs for the various elements, such as Labor, Materials and Subcontractors to the appropriate work packages in the work breakdown structure will establish a Total Budgeted Cost (T.B.C) for each work package. There are two approaches to establishing  the T.B.C for each work package. One is a top down approach , in which Total Project Cost (For labor, materials and so forth) are reviewed in relation to the work scope for each work package, and a proportion of the total project cost is allocated to each work package.

The other is a bottom up approach, which is based on an estimate of the costs for the detailed activities associated with each work package. The project costs is usually estimated when the proposal for the project is prepared, but detail plans are not usually prepared at this time. At the start of the project, however, detailed activities are defined and a network plan is developed. Once detailed activities have been defined, time, resource, and cost estimates can be made for each activity. The T.B.C for each work package will be the sum of the costs of all the activities that make up that work package.

Figure 1.0 illustrates the allocation of costs to individual work packages in the work breakdown structure for a $ 600,000 project. The amount allocated to each work package represents the T.B.C for completing all the activities associated with the work package. Whether the top down or the bottom up approach is used to establish the total budgeted cost for each work package, when the budgets for all the work packages are summed, they can not exceed the total project budgeted cost. 

Figure. 2.0 is  a network diagram for a project to make a specialized automated packaging machine and install it at the Customer's factory. The machine will insert the customer's product into boxes rolling by at high speed on conveyor. The project consists of three activities, and the network diagram shows the duration for each activity. 

Figure 3.0 shows the work breakdown structure with the total budgeted cost for each work package.

2. Developing the Cumulative Budgeted Cost

        Once a total budgeted cost has been established for each work package, the second step in the project budgeting process is to distribute each T.B.C over the duration of its work package. A cost is determined for each period, based on when the activities that make up the work package are scheduled to be performed. When T.B.C for each work package is spread out by time period, it can be determined how much of the budget should have been spent at any point in time. This amount is calculated by adding up the budgeted costs for each time period up to that point in time. This total amount, known as the Cumulative Budgeted Cost (CBC), is the amount that was budgeted to accomplish the work that was scheduled to be performed up to that point in time. The CBC is the baseline that will be used in analyzing the cost performance of the project.

        For the packaging machine , Figure 4.0 shows how the T.B.C for each work package is spread over the time periods,  based on the estimated durations shown in Figure 2.0, also shown is the period  by period  budgeted cost for the entire project, as well as its cumulative budgeted cost (CBC). Figure 4.0 indicates that $ 32,000 was budgeted to accomplish the work that was scheduled to be performed through week 5. The Period over which budgeted  costs are spread usually are determined by the earliest start and finish times for the activities in the baseline project schedule (adjusted to take into account resource leveling or resource limited scheduling)

With the CBC value's, its possible to draw a cumulative budgeted cost curve to illustrate budgeted expenditure over the duration of project. Figure 5.0 shows the cumulative budgeted cost curve for the packaging machine project. Although the table in Figure 4.0 and the cost curve in Figure 5.0 display cumulative budgeted cost for the total project, a similar table and curve can be made for each work package, if desired.

            The CBC for the entire project or each work package provides a baseline against which actual cost and work performance can be compared at any time during the project. It would be misleading to merely compare actual amounts expended to the total budgeted cost for the project or work package, as cost performance will always look good as long as actual costs are below the T.B.C.

Cost Control Management

1. COST CONTROL

This is the process of monitoring the status of the project budget and managing changes to the cost baseline. It involves taking the cost baseline and performance data about what has actually done in order to determine the work accomplished against the amount spent.

Monitoring the expenditure of funds without regard to the value of work being accomplished for such expenditure has little value to the project other than to allow the project team to stay within the authorized funding. The key to effective cost control is the management of the approval cost performance baseline and the changes to that baseline.

For those projects that are funded at various stages and output this process are described below.

2.     COST CONTROL INPUT

2.1.  Project Management Plan

The project management plan described above contains the cost performance baseline, which can be compared with the actual results to determine if a change, corrective action or preventive action is necessary. It also contains the cost management plan that describes how the project costs will be managed and controlled.

2.2.  Project Funding Requirement

The cost baseline described above and need to reflect the cash flow needs of the project including management reserves and contingencies.

2.3.  Work Performance Information

This includes information about project and also includes costs that have been authorized and incurred, and estimates for completing project work.

2.4.  Organizational Process Assets

These include existing formal and informal cost control related policies, procedures and guidelines, cost control and the monitoring and reporting methods to be used.

2.5.  Cost Controls: Tools and Techniques

Earned Value Management (E.V.M), forecasting, the T.C.P.I (To Complete Performance Index), and performance reviews are the main techniques used, along with the project management software. Earned Value Management takes a snapshot of the present moment to see how the project is doing.

The techniques for forecasting and T.C.P.I shows how the future of the project will evolve given how the project is doing now. The performance reviews compare the past performance to see how the project has evolved up until the present moment.

Reserve analysis takes into account the extra layers on top of the cost estimates, the contingency reserves (which are added to the cost estimates to get the cost baseline) and the management reserves (which are added to the cost baseline to get the project budget). It should be decided whether any unused reserves are going to be left in the project budget, or whether they will be taken out.

2.6.  Earned Value Management (EVM)

It is defined as follows:

Earned Value Management (EVM) is a methodology that combines scope, schedule and resource measurements to assess project performance and progress . It is a commonly used method of performance measurement for projects. It integrates the scope baseline with the cost baseline, along with the schedule baseline, to form the performance baseline, which helps the project management team assess and measure project performance and progress.

It is a project management technique that requires the formation of an integrated baseline against which performance can be measured for the duration of the project.

The Earned Value compares the money spent ($130 K) with what should have been spent ($150 K). This means that:

      Work to the notional value of $140 K has been done but, $130 K has actually been spent. There fore the project is $10 K under its planned cost at this point.

Also the project has only completed $140 K of work as opposed to the $150 K that was planned.

       This means that the project is $10 K behind schedule.

It may seem strange to express time in dollars but the reason it makes sense is because time is money.

2.7.  Forecasting

As the project progresses, the project team can develop a forecast for the estimate at completion that may differ from the budget at completion costs. The most common approach is a manual, bottom up summation by the project manager and project team.

2.8 To Complete Performance Index (TCPI)

This is an earned value term which describes the performance needed for you to achieve your earned value targets, and hence to control cost.

2.9 Performance Reviews

These compare cost performance over time, schedule activities or work packages over running the budget, and estimated funds needed to complete work in progress. They are used to determine those areas where costs are under or over performing, and yet again uses earned value management to compare actual results with the cost baseline and hence the ability to be able to control cost via forecast trends and indexes. 

2.10 Reserve Analysis

Monitors the status of contingency reserves and management reserves. Unused contingency reserves for probable risk events that do not occur may be removed from the project budget.

3. Cost Controls: Outputs
This process will create the following outputs:

3.1 Work Performance Information

It is important to capture all of the relevant costs when measuring progress. This information should be communicated to the project team and concerned stakeholders on a regular basis.

3.2 Cost Forecast

These determine the extra funding that will be required based on the actual costs accrued so far. Earned Value can help forecast not just remaining costs but also the required total cost for the project. This information should be communicated to the project team and concerned stakeholders on a regular basis.

3.3 Change Requests

These refer to cost related change request of course, may be needed if the control cost process shows that the project will be costing more or less than the cost baseline. In this case it changes will be needed to bring the project back on track.

3.4 Project Management Plan Updates

This relates to any changes such as those to the cost baseline or the cost management plan. It may also relate to other aspects of the project management plan for example a modification to project scope.

3.5 Project Document Updates

These include cost estimates and are normally needed as a consequence of project plan updates.

3.6 Organizational Process Assets Updates

These include, causes of variances, corrective action chosen and other types of lessons learned from project cost control in order to improve control cost management in the future projects. If either the work performance information or the cost forecasts indicate that there is a variance in either the cost or schedule performance of the project that needs correcting, then a change request may be recommended.

• Corrective action aims to reduce the variance
• Preventive action aims to prevent the variance from growing larger in the future.

It may happen, however, that the variance is so large that the cost baseline is determined to be unrealistic, in which case it may be suggested that the cost baseline itself is changed.
In any case, these change requests are outputs of this process, but then are inputs to the process in the integration management knowledge are called process Perform Integrated Change Control.