On average, 35-50% of craft worker’s time is nonproductive, meaning work is not getting done due to unresolved constraints, such as a material shortage, a hold-up on another area of the project, a labor shortage and more. Though nonproductive time may never be completely eliminated, implementing best practice planning and scheduling methodologies can greatly improve efficiency. One of these best practices is short interval scheduling (SIS).
Short interval scheduling is a process that addresses the dynamic nature of executing work in the field, continually evaluating dependencies and other constraints to keep work flowing smoothly. It requires detailed planning to ensure the crews have what they need when they need it, and sets forth safety, quality, productivity, cost and completion expectations before the work begins.
SIS is comprised of six key steps:
Identify and list the tasks required to the next level of granularity.
Based on experience, determine the logical sequencing of the tasks and what tasks can be executed concurrently.
Assign the mix and number of crafts person to each task.
Compare the plan to the master schedule and the estimate.
Make adjustments as required.
As with any new process, there’s a learning curve to go through and there may be resistance. At first, field personnel might feel as though they are being micromanaged, but once the supervisors and crews realize the benefits of having what they need when they need it, they will become advocates of the process. If implemented effectively, management will see improved safety, quality, productivity and schedule reliability performance.
Short interval scheduling is part of the foundation for many different workplace concepts. Lean construction, Just in Time (JIT), and agile project management all came about due to the failures of the “waterfall method” of scheduling. Before these were put into practice, planners would develop a very detailed project master plan, in a vacuum, for large-scale projects—without consideration of the inevitable change that occurs.
Short interval scheduling aligns with “lean” and agile methodologies in the sense that the goal is to break the work down to a manageable scope and duration that ties back to project milestones, removes the constraints, creates a continuous flow, and enables rapid learning.
Short interval scheduling improves productivity and reduces labor waste. This is possible because SIS helps supervisors to identify actual work done vs. what was planned, to evaluate constraints and opportunities. Additionally, short interval scheduling drives visibility throughout the crew and entire firm, keeping everyone on the same page.
Short interval scheduling helps better manage labor, tools and materials needed for a particular day and identify drivers of waste and rework. In the short term, this keeps the team on track for project completion and reduces waste. In the big picture, short interval scheduling drives reduced labor costs leading to increased profitability and growing revenue, thus helping the organizations grow their bottom line.
Similar to short interval scheduling, a work breakdown structure (WBS) helps segment a project into various work scope groupings that progressively become more granular to enable the stakeholders to better plan and execute the work. WBS essentially takes one large project and makes it a collection of smaller projects. A WBS starts with the outcome or product—the ‘end goal’ of the answer. The lowest level of the WBS includes Work Packages. Work Packages consist of one or more tasks.
Short interval scheduling breaks it down one step further into the tasks associated with the work package—when it’s going to be done, who is going to do it, and the performance measures associated with each task. In addition, SIS should establish productivity and labor cost goals that align with the budget. A Work Breakdown Structure and Short Interval Scheduling go hand in hand to break huge projects into manageable tasks, keeping the overall project on track.
Ready to dive right in? Download our SIS template and follow along below:
Define the scope of work and have available the estimated production units (man-hours/unit of measure).
Determine when the work needs to start and finish (reference the project master schedule).
Make a grocery list of the tasks involved.
Sequence the tasks logically (first things first, what tasks can be performed concurrently?)
Apply manpower to each task (workers per task per day). Note: this will determine the duration for each task.
Calculate the planned total hours, planned crew composite rate and planned completion.
Compare the plan against the estimate and the Master Project Schedule.
Make adjustments as required to align the plan with the Estimate and the Master Project Schedule.
In your planning tool of choice, identify when you need what: Drawings, specifications, material, construction equipment, tools, consumables, inspections etc.
Identify the safety hazards associated with each planned task, how the hazards will be mitigated and who will be responsible for implementing the mitigation measures.
Short interval scheduling might seem intimidating, but once you get started it’s more manageable. Keep these ideas in mind when getting started to be successful!
Though it may not be in the form of the defined process we suggest above, some sort of short interval planning and scheduling takes place on every construction job, every day that work is being performed. Discussions may occur in groups or with individuals, crafts are assigned to frontline supervisors, and those crew leaders, at some point, will tell their people what to do and when to do it.
Introducing a standard, more effective, efficient method of short interval planning and scheduling offers many benefits, but may face varying levels of resistance. Many frontline supervisors simply have never been trained on how to plan and schedule. Others may take pride in their ability to make quick decisions when dealing with chaos. Effective planning takes time and is not easy, and neither is adjusting to change
Having had extensive experience training and implementing short interval planning and scheduling, we typically find the frontline guys and gals are not the problem. They want to have what they need and it feels good when the work is going smoothly. It's embarrassing and demoralizing when they have to face their crews every morning and can’t get the work done because they don’t have what they need due to some out of control upstream process or people they depend on dropping the ball.
Instead, the field crew often resists the adoption of a new planning and scheduling processes. No one likes change, and it can be hard to adjust after doing things the same way for years.
Short interval scheduling can be extremely beneficial, but also can be overwhelming when you’re just getting started. Labor management software solutions (while it cannot replace the need for experienced frontline supervisors and crews) can simplify the SIS process, with the following benefits:
Short interval scheduling reevaluates the progress of a project regularly and adjusts the schedule to ensure the project happens as efficiently as possible. It ties in with other strategies, like lean, agile, and work breakdown structure to build a comprehensive strategy. Since SIS helps supervisors to identify actual work done vs. what was planned as well as evaluate constraints and opportunities, it helps improve productivity and reduce waste.