Description
The As-Planned vs. As-Built method is a widely used observational technique in delay analysis. It involves comparing the original planned schedule (contractual baseline or approved baseline) with the actual as-built schedule to measure differences and identify delays. This method is relatively straightforward and can be performed through graphical comparison using a Gantt chart or by comparing activity start and end dates in a spreadsheet.
For projects with a large number of activities and sequence changes in their execution, the analysis can become more complicated, having to analyze the construction logic, activity durations, possible interferences, and determine the causes of each variation.
To conduct the delay analysis using this methodology, the following steps are followed:
- Identify the accepted baseline and project activity dates and sequence.
- Compare activity dates following the original baseline logic, focusing on the critical path of the project.
- Identify start delays, extension durations, and end delays by comparing and determining significant delay events and potential mitigation strategies such as acceleration or out-of-sequence deployment.
- Identify and assess simultaneous delays, such as concurrent or pacing delays, to evaluate their impact on the critical path.
- Analyze any delays that affect the critical path to determine their root causes.
- Consider time extensions granted to the contractor and any recovery plans, as they may impact the analysis.
The critical path of the baseline spans from design and basic engineering to civil works, construction, and commissioning. To effectively utilize the As-Planned vs. As-Built technique, certain minimum requirements should be met:
- Reliable data on activity completion and the baseline schedule.
- The project should be relatively simple with fewer activities.
- Minimal difference between the actual sequence of activities and the planned sequence.
Example
The total delay of the project is 18 calendar days, however, if we activate the column for variation between the end of the activity and the end of the project baseline, Primavera P6 shows us a delay of 15 days. Primavera P6 may display delays differently based on working hours in the assigned calendar. This is because the difference between both dates is calculated considering the working hours of the assigned calendar. To calculate the delay of each activity in calendar days, exporting data to Excel and calculating the differences between dates can be a quick and efficient option.
After identifying delays, the responsibility for each delay affecting the critical path should be determined. Assigning responsibility based on contractual agreements and other factors will allow for a comprehensive understanding of the causes of delay. If we consider the promoter responsible for the design and the procurement of materials and the contractor responsible for the rest of the activities and that there was a day of delay in the construction due to adverse weather conditions, the following conclusion can be reached.
Analyzing only the delays of the activities of the critical path of the executed project, we have as a result that, of the 18 days of delay, 14 are the responsibility of the promoter (excusable and compensable) and 3 are the responsibility of the contractor (not excusable or compensable) and 1 excusable but non-compensable day due to force majeure.
In conclusion, the As-Planned vs. As-Built technique provides valuable insights into project delays, allowing stakeholders to identify accountable parties and assess the impact on the critical path. By following the outlined steps and meeting minimum requirements, this method can be effectively applied to delay analysis in various construction projects.
Strengths of the As-Planned vs. As-Built (APAB)
- Simplicity and Ease of Understanding: APAB is a straightforward method that can be easily performed by planners with little experience in construction projects and delay analysis. It is also easily presented and understood. The simplicity of this method ensures that the results are clear and comprehensible to all parties involved. This straightforward approach increases the likelihood of trust in the analysis and enhances the chances of successful claim resolution.
- Cost-Effectiveness and Time Efficiency: One of the significant advantages of APAB is its minimal resource requirements. Unlike more complex delay analysis methods, APAB does not demand sophisticated planning software or extensive data processing. This translates to cost savings and a reduced need for specialized expertise or software. Additionally, APAB allows for the generation of acceptable and defensible results in a relatively short period of time. The ability to quickly obtain relevant insights makes APAB a practical choice for time-sensitive situations.
- Minimal Documentation Requirements: Another strength of the APAB method is its modest documentation needs for a simple analysis. Only essential documents such as the as-built dates, the agreed-upon planning schedule, and justifications for delays affecting the critical path of the completed project are necessary. This streamlined documentation process simplifies the analysis and avoids the need for excessive paperwork or data gathering.
- Effective for Simple Projects: APAB is particularly well-suited for simple projects with a limited number of activities and straightforward sequences. In such cases, the method provides accurate and relevant delay analysis without the need for more complex approaches. It is an efficient choice for projects that do not have significant variations from the original planned schedule.
Weaknesses of the As-Planned vs. As-Built (APAB)
- Limited to Complex Projects: One of the significant weaknesses of APAB is its limited applicability to complex construction projects with extended durations and significant variations in the sequence and strategy of activities. In such cases, it becomes challenging to obtain realistic and reliable results using this methodology, as it may overlook critical aspects of the project’s execution.
- Unsuitability for Projects with subcritical paths: APAB is not suitable for projects with activities that have minimal margin of delay (total float) or multiple subcritical paths. The method fails to consider such constraints and may lead to inaccurate delay assessments. Additionally, changes in the critical path over time cannot be effectively analyzed, limiting the depth of the analysis.
- Concurrent Delays: Concurrent delays, where multiple delays occur simultaneously and impact the critical path, are not adequately addressed by the APAB method. This can lead to difficulties in accurately attributing responsibilities for delays and their effects on the project timeline.
- Subjectivity and Dependence on Analyst’s Experience: The reliability and accuracy of the APAB analysis heavily rely on the knowledge, experience, and judgment of the technician performing the analysis. The method lacks objective criteria, making it susceptible to potential biases and subjectivity in its interpretation.
- Not considering contemporaneous Critical Paths: APAB only considers the As-built critical path and overlooks prospective critical paths in contemporary project schedules and the critical decisions that may have been made based on them. This omission may result in missing essential insights into project planning and management decisions.