How to calculate Engineering Working Hours

Working hours create realistic project schedules. It enables accurate resource allocation, cost estimation, and critical path analysis. Project managers can assess resource productivity and adhere to project constraints, such as night shifts or specific time windows. Working hours aid in effective communication, ensuring stakeholders understand when activities are scheduled. It’s important for managing projects in multiple time zones.

In this article, we will explain how to calculate the working hours for Engineering work

( ShopDrawing Submittal & ShopDrawing Resubmittal )

From a practical Point of view, the P6 Schedule will not contain 100% of all project shop drawings, We will have a summary level of the Shop Drawings. Therefore we need to do an intermediate step to calculate the working hours accurately

A. Define the number of ShopDrawings

Usually, the total number of the shop drawings is not inserted in the Time schedule but we insert a summary for it to reduce the number of activities in Primavera, and to track the Shop drawing process we create the Shop Drawings log

This is the Summary of Shop Drawings in the Time Schedule

The Shop Drawings log

The shop drawings log contains all the detailed drawings names and date

We need to link the Shop Drawings log to the Shop Drawings in the P6 Schedule to calculate the number of the sheets ( shop Drawings ) for each activity in the schedule

Now we need to create an Excel sheet to link the summary activities to the detailed one
This means every activity in your schedule may contain one or more shop drawings in the Log

The Link Sheet

This sheet contains a detailed drawing linked with the main activities in Primavera P6

Create a Pivot table to count the detailed drawings to the summary one

From the Insert menu choose Pivot table

Choose the wanted range for the sheet and Select the new worksheet

This is the layout of the Pivot table
we will add the columns in Rows and Values to make the table count every repeated drawing under the summary drawing

Once you put the Activity name and ID in the Rown This table will show up but we need to see the Activity name beside the Activity ID, Click on the inverted triangle beside the Activity ID

After Clicking on the inverted triangle this will show up :
From “Subtotals & Filters “ Choose “ None “

Then Go to “Layout & Print“ then choose “Show items labels in tabular form” then press ok

This is the shape of the Pivot table, But we need to count the detailed drawings in every summary one

We will add a new column in the Pivot table

Once you add the shop drawings Title in “ Values “ the Column of “ Count of ShopDrawings Title” will show up

This is the Pivot table layout, Once you add new shop drawings in the main Table and refresh it, It will be here and counted

B. Agree about productivity rate with your Team

We can agree with our technical office team about the required hours per drawing sheet
Let’s assume that every sheet takes 4 HRS
Here we multiply the Count of shop drawings with the 4 HRs, and it will give you the working hours for the summary shop drawings