Construction Scheduling: what is it used for and how is it prepared?

Construction Scheduling: What is it used for and how is it prepared using a software?

The construction scheduling is a diagram which has the function of defining the distribution of costs and the various work sections in time.

In a simplified way, the time schedule can be achieved by drawing up a two-column table in which we have:

• the reference periods;
• the costs to be sustained in the corresponding period.

Basically it defines a document that forecasts the time necessary to meet project completion.

These kinds of representation may seem hard to understand but normally a good way to simplify reading is to combine textual data with a graphical representation using a Cartesian diagram or Gantt chart.

The Gantt chart, in this case, is a graph in which each work section or works classification, also identified in the project cost estimate, is represented by a bar with a certain length that gives an indication of the time scheduled for execution. The diagram should also show the partial and progressive amounts expected to be paid during the reference periods too.

Starting from the items defined in the bill of quantities or construction estimate, we can easily proceed to form individual groups, for example:

• demolitions
• foundation structures
• super-structures
• partition walls
• floorings
• technical installations
• etc.

Works schedules and timing: how to prepare one using a software

You can draw up the schedule of works with the help of a software, PriMus KRONO by ACCA software.

For this purpose, the software must allow the operator to:

1. create the various phases of work and show them in the time schedule
2. set up folders and activities
3. build up a Gantt chart
4. manage different levels of productivity for the activity periods
5. identify when an IPC will be issued
6. generate a project time schedule and a separate one for executionquery the financial plan in specific moments

Building up a works schedule using PriMus KRONO

The time schedule may be divided into several levels, according to the desired structure, by the use of:

• activity
• categories of work (folders)

Activities can of course be managed graphically with specific functions that allow the operator to:

• move them along the time-line
• define duration
• split them into multiple periods
• connect them up by identifying critical paths

Time schedule activities

It is essential that time -schedule activities are defined with maximum precision. Let’s take for example the activity “structural works”, which can be divided into a further sub-category. We’ll call it, “sub-structures”, in which the following items are identified:

• formworks
• steel reinforcements
• cement conglomerate

The chart shows that each of these resources, quantity, duration, productivity and number of workers per day for each activity period both in the project and execution phases, can be easily managed:

Time schedule management

With this works time-scheduling software, you can:

• manage and customize the weather conditions
• schedule and plan work activities in relation to bank holidays and working days
• choose an appropriate time scale
• define a representation layout
  define a new start date for activities, periods or for the entire time schedule
• show any work interruptions or suspensions graphically
• customize the bar styles individuall

Financial Plan Management

The management of the Financial Plan allows you to view:

• timing necessary to completion of works
• anticipations
• sureties
• payments
• etc.

With these economic and financial plans, the technician can view the amounts calculated on the basis of the daily productivity levels at a given date, in both the planned works phase and the works execution phase. The Financial Plan can also be queried to identify when IPC (interim Payment Certificate) deadlines are to be met.

The project and works execution time schedule

The time schedule can be divided into:

• the project time schedule
• the works execution time schedule

It’s obvious that the works execution time schedule indicates in detail which work phases have been completed with specific quantities and dates, etc. These phases are represented graphically by specifying the quantitities for each Activity or Period.

Printing the time schedule and accompanying reports

The last step is represented by actually printing the documents, such as for example:

• Project time schedule
• Works execution time schedule
• Activity tables
• The amounts and dates table
• The time schedule report
• The works execution report