Most owners receive the contractor's baseline schedule as a PDF, glance at the finish date, and file it. That is a mistake: the baseline is the yardstick for every delay claim, extension request and progress payment argument that follows, so it deserves a proper review before you accept it.
Why the baseline matters more than the finish date
A finish date on a bar chart tells you nothing about whether that date is achievable. What matters is the network behind it: the activities, the logic that connects them, and the float that results. If that network is weak, the schedule will "move" whenever it is convenient, and you will not be able to tell real delay from paper delay.
Ask for the native scheduling file (for example, the Primavera P6 .xer or Microsoft Project .mpp file), not just a PDF. You cannot review logic or float from a picture.
Critical path and total float, in one picture
The critical path is "the longest (time) sequence of activities in a project plan," and a delay on it pushes out the project end. Total float is "the late start time minus the early start time" for an activity: how long it can slip before it delays completion. Both definitions come from a PMI Global Congress paper by William J. Scott.
The owner's baseline schedule review checklist
A useful screen is the DCMA 14-point assessment, which many scheduling tools build in. The thresholds below are as documented in Deltek's Acumen help pages. Treat them as flags for questions, not automatic rejections.
- Logic and open ends. Every activity should have at least one predecessor and one successor; Joseph Lukas calls this "a basic scheduling rule" in a PMI paper on common scheduling mistakes. DCMA flags missing logic above 5% of incomplete activities. Open ends hide delay because nothing downstream reacts when they slip.
- Relationship types, leads and lags. DCMA expects finish-to-start links to make up at least 90% of relationships, no leads (negative lags) at all, and lags on no more than 5% of links. Lags should be explained, not used as invisible durations.
- Constraints. Hard constraints should not exceed 5% of incomplete activities. A "must finish on" date overrides the logic and can produce negative float, as Lukas warns. Ask why each constraint exists.
- Total float. DCMA flags incomplete activities with more than 44 working days of total float. Large float usually means missing successors, not genuine flexibility. Any negative float in a baseline needs an explanation and a recovery plan.
- Durations. DCMA flags activities over 44 working days in the near-term window and expects no more than 5% of them. Ask for long activities to be broken down.
- Critical path test. Add a delay to a critical activity in a copy of the file and confirm completion moves by the same amount. If it does not, the critical path is broken by a constraint or missing link.
- Invalid dates. Actual dates after the status date are impossible and point to sloppy updating. DCMA allows none.
- Resource loading. DCMA checks for activities with duration but no resources. At minimum, check that crew sizes and quantities make the durations believable, and that the contractor has not stacked trades in the same area at the same time.
- Owner activities. Look for your own obligations: approvals, owner-supplied equipment, permits, tenant moves. If their durations are unrealistic, you have just agreed to a delay you will own.
Updates versus the baseline
Once accepted, the baseline should be frozen. Every monthly update should be compared against it, not against last month's update, or slippage disappears in small steps. Ask for a narrative with each update that explains changes to logic, durations and the critical path. DCMA's missed-task and baseline execution metrics measure exactly this: how many activities finished later than planned.
Unexplained logic changes are the single biggest warning sign we see. A schedule that keeps the same finish date while the critical path shifts every month is usually being managed to a date, not to the work.
Who owns the float?
Float ownership decides who benefits when non-critical work slips. A 2021 Stoel Rives article describing US case law notes that, absent a contract clause, the general rule is that the project owns the float on a first-come, first-served basis, and recommends dealing with it expressly through a float-sharing or float-allocating clause. Read your contract's scheduling and delay provisions before the first extension request arrives, and confirm with your lawyer how they would be interpreted in Ontario.
Frequently asked questions
Should owners formally approve the contractor's schedule?
Prefer "reviewed and accepted" with written comments over a bare approval. Acceptance should confirm the schedule is a reasonable basis for measuring progress, not that you guarantee its logic.
How long should a baseline schedule review take?
It depends on schedule size and quality. Build time for one round of comments and a resubmission into the contract, so the baseline is accepted before significant progress billing.
What is the difference between total float and free float?
Total float is how long an activity can slip before it delays completion. Free float is how long it can slip before it delays the early start of the next activity.
The bottom line
The baseline schedule is a contract document in all but name. A disciplined review at the start is far cheaper than an argument about delay at the end. If you want an independent check, see our project controls services or read how an owner's rep differs from a project manager.
Want a second set of eyes on a baseline before you accept it? Book a 30-minute call with Ben.
Sources: PMI, Follow the Yellow Brick Road (the Critical Path), W. J. Scott, 2011; PMI, Is Your Schedule Correct? Common Scheduling Mistakes and How to Avoid Them, J. A. Lukas, 2007; Deltek, DCMA 14-Point Assessment Metric Descriptions; Stoel Rives, Who Owns the Project's 'Float,' and What Should Be Done About It?, 2021. This article is general information, not financial or legal advice.