Progress Calculation Procedure for Engineering

Normally in an EPC project, progress calculation procedure for engineering deliverables is developed and used to monitor project performance against man hour spent. When working with progress calculation, you should know the level of reporting. In a typical project, engineering progress is measured as level 2 (phase wise) and level 3 (engineering discipline wise) and level 4 (document wise). Refer to the following procedure to calculate engineering progress,

1) Engineering progress for each document (Level 4) = the sum of the product of weight factor for each work step and engineering progress for each work step

2) Engineering progress for each discipline (level 3) = the sum of the product of weight factor for each document and engineering progress for each document

3) Calculate total engineering progress (level 2) = the sum of the product of weight factor for each discipline and engineering progress for each discipline

How to Get an Engineering Drawing Progress – Level 4

The progress calculation is done based on engineering work steps and their weight factors for an engineering drawing. See the below sample work steps and weight factors.

Sample weight factor for each work step for each engineering drawing

Weight factor is calculated based on effort required for each work step for a particular drawing/document. The ratio of weight factor for each work step could be different depending on your project team’s expert judgment. The following work steps are required to produce an engineering drawing as minimum.

1. Start

2. Study/Preparation

3. Issue for internal review

4. Issue to client

5. Approval by client

6. Issue for construction

The projects I involved describe the weight factors for the above work steps are as follows;

1) 5% (0.05) of total hours for “Start" work step

2) 45% (0.45) of total hours for "Study and preparation" step

3) 10% (0.10) of total hours for "Issue for Internal Review"

4) 10% (0.10) of total hours for "Issue to client"

5) 15% (0.15) of total hours for to get "Approval by Client"

6) 15% (0.15) of total hours for "Issue for construction"

The sum of total weight factors for all work steps must be 100% (1).

Let’s find out how a piping drawing progress is calculated. Suppose a piping isometric drawing design has been completed 50% of “Study and Preparation” work step. See the details calculation and below figure for easy understanding. 

Progress for a piping isometric drawing at that stage = Weight factor for “Start” work step (0.05) x progress for “Start” work step (100%) + Weight factor for “Study and Preparation” (0.45) x progress for “Study and Preparation” work step (50%)

Therefore, the actual progress for that drawing up to 50% completion of study and preparation step is 27.5 %. The actual progress would be 50% when “Study/Preparation” work is completed 100%.

Progress Calculation for Engineering Specification/Requisition-Level 4 

Progress calculation for an engineering specification/requisition is done using the same exercise for engineering drawing. The only different is its work Step and weight factor as weight factor for each work step for each specification/requisition is required to calculate the quantity progress.

Sample weight factor for each work step for each engineering specification/requisition

The following are work steps and weight factors for a production of engineering specification/requisition.

1) 5% (0.05) of total hours for “Start" work step

2) 45% (0.45) of total hour for "Study and preparation" step.

3) 15% (0.15) of total hours for "Issue to client"

4) 20% (0.20) of total hours for to get "Approval by Client"

5) 15% (0.15) of total hours for "Issue for construction/Purchase” Once again, the sum of total weight factors for all work steps must be 100% (1).

How to Get Engineering Progress by Discipline -Level 3 

To calculate discipline wise (level-3) engineering progress, in other word, physical progress for an engineering discipline = the sum of the product of weight factor for each document and engineering progress (quantity) for each document.

How to find weight factor for engineering document

Weight factor calculation for engineering document is required to calculate engineering progress for each discipline. Engineering documents are normally categorized drawings, specifications, requisitions and information documents. P&ID drawings, isometric drawings, pump GA, foundation drawings, etc. are in drawing category. Material specification, equipment/piping fabrication and erection specification and Instrument cable specification are in specification category. REQ for piping material, REQ for pump/compressor/blower and etc. are in requisition category.

Weight factor for an engineering document = budgeted man hour for a document/total budgeted man hour for all documents in each discipline,
Assume the budgeted man hour for an iso metric drawing is 200 and 10,000 hours for all piping documents. Therefore, weight factor for that iso drawing is (200/10,000) 0.02.

Progress Calculation for Mechanical Engineering Discipline

Progress calculation for mechanical engineering discipline = the sum of the product of weight factor for each document and the actual progress of each document in mechanical discipline for a particular project.
For instance, a project includes the mechanical scope required to produce a list of drawings and documents and the work is in-progress. Suppose a table of mechanical documents are shown as the following,



Weight factor for pump data sheet is 0.0356 obtained based on 200 budgeted hours/ 5470 total budgeted hours of mechanical discipline.

The progress data in “Quantity Progress (% complete)" column is referred to the document progress calculation based on work step completion and work step weight factor.

For example,

Quantity Progress (% complete)" for pump data sheet = 5% x 100%+45%x100%+15%x100+20% x100%+15%x33% = 90% ,

This is the same calculation method used for a piping isometric drawing progress as explained on above.

The progress data in "Weight Progress" which also known as physical progress column is referred to the progress calculation based on document weight and Quantity Progress (% Complete).

For example,

Physical Progress of pump data sheet document = 0.03656 x 90% = 3.3%,

Finally, the total progress for mechanical engineering section, 37.8% is the sum of weight progress for each document.

Progress calculation procedure for process, piping, civil, structure, electrical and instrumentation is done using the same methodology as mechanical discipline.

How to Get Overall Engineering Phase/Stage – Level 2 

Progress data for engineering phase can be obtained using the same exercise like discipline wise progress calculation. The difference is the way how you want to group it. That means weight factor for each engineering discipline is required to analyse the total progress of all disciplines.
. See the below formula to get overall engineering progress.

Progress for engineering phase/stage = the sum of the product of weight factor for each discipline and progress for each discipline, see how weight factor for each engineering discipline as below.

How to find weight factors for engineering disciplines

Weight factor = budgeted hour for each discipline/Total budgeted hour for all discipline for a particular project,

For example

Assuming that budgeted man hour for mechanical, process, piping, civil, structure, electrical and instrumentation are listed as table below.

Weight factor for mechanical engineering discipline = 5470 (Budgeted man hour) / 31370 (Overall engineering man hour) = 0.1744

Progress Calculation for Overall Engineering

Mechanical engineering progress is 37.8 % as stated above and assuming that the individual progress for other disciplines is listed as below table.

Then, Overall Engineering phase/stage progress = the sum of the product of weight factor for each discipline and physical progress for each discipline,

= 0.1744 x 37.8% + 0.0956 x 50% + 0.2550 x 20% + 0.1020 x 30% + 0.1116 x 25% + 0.1275 x 15% + 0.1339 x 13% = 26%


Download sample progress calculation sheet to learn more.