Overview of Scheduling Techniques in Construction Projects
In construction project management, selecting the right scheduling technique can significantly impact time, cost, and resource efficiency. Two widely used approaches are the Critical Path Method (CPM) and Location-Based Scheduling (LBS). While CPM has been a longstanding industry standard, LBS is increasingly recognized for its spatial awareness and effectiveness in managing repetitive workflows [Kenley & Seppänen, 2010].
This article compares these two methods, highlighting their principles, differences, and suitability for complex projects such as high-rise buildings, linear infrastructure, or multi-zone airport terminals. By understanding their strengths and limitations, project planners and decision-makers can choose the most appropriate method—or integrate both—for optimal outcomes.
Importance of Choosing the Right Scheduling Method for Complex Builds
Scheduling is not just a matter of timelines—it is a strategic instrument for managing cost, resources, risk, and legal compliance. Among available techniques, the Critical Path Method (CPM) remains the industry benchmark. It is widely adopted in provisions of contract, such as FIDIC Sub-Clause 8.3, and continues to be essential for progress monitoring, extension of time (EOT) claims, and delay analysis [FIDIC, 2017].
Clients, consultants, and contractors still demand CPM schedules because they are logic-driven, easy to audit, and legally defensible [AACE International, 2021]. Project approvals, payment schedules, and forensic analyses are frequently tied to CPM outputs. Its robustness in handling interdependencies makes it indispensable in complex projects with varied trade overlaps.
However, Location-Based Scheduling (LBS) offers significant advantages in projects with repetitive, spatially distributed activities, such as high-rise towers, hotels, tunnels, or airport terminals [Kenley & Seppänen, 2006]. Unlike CPM, which focuses on logic links and durations, LBS organizes work based on physical zones and crew flow. The Line of Balance (LOB) chart is central to LBS, allowing planners to visualize how crews move through each zone without interruption. In projects where preferential relationships are more prevalent than hard logic links, and out-of-sequence work is likely, LOB-based monitoring and delay analysis play a critical role. In projects where out-of-sequence work is predominant, CPM-based delay analysis may yield less accurate results compared to a LOB-based approach, particularly when applying the as-planned versus as-built method.
LBS helps avoid trade stacking, idle time, and handover delays by aligning work packages with real-world location sequencing [Soini, Leskelä & Seppänen, 2004]. When integrated with Lean Construction and 4D BIM tools, LBS improves productivity and reduces waste [Hamledari et al., 2021].
Together, CPM and LBS serve complementary roles—CPM provides the contractual backbone, while LBS optimizes production efficiency. The key is to choose or combine them based on the specific needs and structure of the project.
In-Depth Comparison of Critical Path Method vs. Location-Based Scheduling
1. Critical Path Method (CPM)
CPM relies on logic links, durations, and dependencies. Each task must be sequenced, and the critical path defines the minimum project duration.
Strengths:
• Ideal for detailed sequencing of complex interdependencies
• Accepted in legal and contractual frameworks (e.g., FIDIC 8.3 programmes) [FIDIC, 2017]
• Easily auditable and adaptable for time-impact analysis (TIA) [AACE International RP 29R-03, 2011]
Limitations:
• Ignores location or crew flow unless custom logic is embedded
• Fragmented visualization of progress across zones or floors
• Inefficient in repetitive work environments without layering techniques [Kenley & Seppänen, 2006]
2. Location-Based Scheduling (LBS)
LBS structures activities around locations (floors, zones, segments) rather than individual tasks. The Line of Balance (LOB) technique is common, visualizing crews moving through zones like production lines [Kenley & Seppänen, 2010].
Strengths:
• Improves crew flow and productivity
• Detects workface clashes and buffer overlaps
• Visual clarity—easily identifies interruptions in zone handovers
• Supports lean planning and just-in-time logistics [Ballard & Howell, 2003]
Limitations:
• Less familiar to stakeholders and auditors
• Requires location-based breakdowns not always present in early WBS
• Limited contractual use unless predefined in technical specifications [Soini et al., 2004]
3. CPM or LBS? How to Choose the Best Scheduling Strategy
| Context | Preferred Method |
| Heavy logic dependencies, regulatory reporting | CPM |
| Repetitive work across floors/zones | LBS |
| Dispute or delay claims | CPM with TIA |
| Optimizing crew movement, Lean Construction | CPM, LBS |
Key Insights and Actionable Tips for Project Managers
Key Takeaways
• CPM is indispensable for contractual compliance, but may not suffice alone for production optimization.
• LBS brings spatial intelligence into planning, aligning better with lean construction and modern digital workflows [Kenley & Seppänen, 2010].
• For linear infrastructure (e.g., railways, pipelines) and high-rise buildings, LBS can significantly reduce idle time and clashes [Soini et al., 2004].
• Hybrid models help teams balance legal defensibility with operational efficiency.
• Training stakeholders in reading LOB charts and using location-based breakdowns improves schedule literacy.
Practical Recommendations
• Define locations and sequences early in WBS
• Align software tools with method
• Ensure delay analysis frameworks match the scheduling method used
• Pilot LBS on segments before full rollout
Final Thoughts: Integrating CPM and LBS for Maximum Project Efficiency
Choosing between CPM and Location-Based Scheduling depends on project complexity, type, and stakeholder needs. Rather than treating them as mutually exclusive, consider a complementary approach that leverages the strengths of both.
At Harmony CMC, we help project teams implement integrated scheduling strategies—combining logic, location, and lean principles—to reduce delays and enhance predictability.
References
- AACE International (2021). Recommended Practice No. 29R-03: Forensic Schedule Analysis.
- Ballard, G., & Howell, G. (2003). Lean project management. Lean Construction Institute.
- FIDIC (2017). Conditions of Contract for Construction – Second Edition (Red Book). Fédération Internationale Des Ingénieurs-Conseils.
- Hamledari, H., Fischer, M., & Zekavat, M. (2021). Automated project schedule validation using BIM and 4D simulation. Automation in Construction, 124, 103544.
- Kenley, R., & Seppänen, O. (2006). Location-based management system for construction: Planning, scheduling and control.
- Kenley, R., & Seppänen, O. (2010). Line-of-Balance Method: Historical Development and Current Applications. Lean Construction Journal.
- Soini, M., Leskelä, I., & Seppänen, O. (2004). Implementation of Line-of-Balance Based Scheduling and Project Control System in a Large Construction Company. Proceedings of the 12th Annual Conference of the International Group for Lean Construction (IGLC-12).
