Good Schedules Have Float
Stu Haney
Stu has over 35 years of experience in the AEC industry. A teacher and a coach by nature, what’s most rewarding for Stu is helping others reach their full potential.
Good Schedules Have Float
Throughout my career in project-based businesses, I’ve been involved in thousands of projects, witnessing every imaginable approach to scheduling. Yet, only a few of these projects were well-managed from a scheduling standpoint. Many factors contribute to scheduling challenges in the “real world,” but one persistent issue stands out: overly optimistic scheduling.
I nearly titled this post Never Let an Optimist Schedule Your Project, because an overly optimistic schedule—one without float—is a recipe for failure. But let’s stick with the constructive message: good schedules have float.
What is Float?
In project management, float (also called slack) refers to the amount of time a task can be delayed without impacting the project’s overall deadline or subsequent tasks. Float acts as a buffer, accommodating unexpected delays while keeping the project on track.
Why Does Float Matter?
A schedule without float is a dream—one detached from reality. It assumes that every task will happen exactly as planned, on the exact day and time anticipated. Unfortunately, this rarely aligns with real-world constraints.
For instance, imagine you’ve scheduled a quality control review. You estimate it will take one day, so you allocate a single day for it. In reality, your reviewer may not be available on that exact day, and finding time later could push subsequent tasks into chaos. Now multiply this scenario by hundreds of tasks, and you can see how optimism quickly compounds into missed deadlines and fire drills as the project nears completion.
Realistic Scheduling Requires Real-World Thinking
Effective schedulers account for uncertainty, variability, and human constraints. They know that:
People aren’t always immediately available.
Tasks may take longer than expected.
Unforeseen issues arise.
Building float into your schedule creates a cushion to absorb these realities. It doesn’t mean you expect delays—it means you’re prepared for them.
By incorporating float, you set up your team, leadership, and client for success. Projects run smoother, fire drills decrease, and you protect the project’s integrity.
So, on your next project, embrace reality: account for uncertainty, and build in float. Your schedule—and everyone involved—will thank you.
