Bid and baseline schedule creation inherently comprise the iterative resequencing of the project’s programmed tasks, durations and relationships that alter the project’s duration and phasing during the schedule development process. Whether aiming to program a Level-1 Summary Schedule typically depicted in monthly increments (later to be enhanced) or a Level-3 Detailed Schedule conveyed in work days for field use, the planning exercise requires a collaborative and communicative instrument in which the project team can vet the logic network.

To generate an instrument that’s easy to modify during the planning phase, graphical tools are utilized to create a Timed-Scaled-Logic-Network (TSLN) that captures the project’s comprehensive scope on a single document. Practitioners of graphical tools refer to this instrument as an Overall Project Schedule (OPS). While CPM scheduling tools can and often are configured to produce a TSLN on a single document, limitations in formatting render their output inferior by comparison to graphical instruments and efforts to implement revisions into the plan more cumbersome than in graphical tools. That’s why Spectrum Consulting plans projects graphically and works with the project team to revise the graphical plan until its accepted and is ready for programming into a CPM tool as the project’s baseline schedule.

Unlike firms who employ graphical tools beyond their limitations to illustrate the project’s initial plan and to utilize them in substitution of CPM tools for routine schedule maintenance, we’re adamant that any resultant depiction of a TSLN devised in a graphical tool does not constitute a Critical Path Method (CPM) schedule because only scheduling tools equipped with built-in CPM engines calculate the required forward and backward passes to indicate each task’s float or slack value. This is why branded graphical tools’ outputs such as an SPS, OPS or a Near Term Schedule never publish the quantified float/slack value next to the task’s description. That’s because they can’t, they’re not scheduling tools.

Due to pervasive contract specifications that mandate general contractors maintain a CPM schedule, it’s our view and the view of the majority of construction management firms acting as owners’ representatives that instruments devised in graphical tools and intended as project baselines or schedule updates are unacceptable and non-compliant with contract specifications for schedule management. Leverage the utility of graphical tools for planning but maintain schedules in CPM tools.