The Golden Rules Of Achieving Flow In Construction

In this blog, I’m going to cover the three critical keys to achieving flow in construction. This concept is vital because it permeates every activity, effort, and aspect of your construction project. These three keys to flow will help you understand how to streamline operations effectively and avoid common mistakes. I’ll also discuss what not to do to achieve flow and touch on some pitfalls of outdated methods like the Critical Path Method (CPM). Let’s dive in!

Why The Critical Path Method is NOT Flow

When you think of flow, you might initially think of the Critical Path Method (CPM). However, CPM is far from achieving true flow. In a CPM schedule, tasks are often linked together based on a work breakdown structure, but this method does not account for the complex nature of construction systems. 

As highlighted by Eli Goldratt in his work on systems thinking, CPM schedules offer a projection that is likely to change dozens of times and often do not mirror how construction actually works.

CPM is similar to having a factory where workers are randomly placed throughout the facility, moving at different speeds, crossing paths, and creating chaos without a system in place to guide them. The result is a lack of flow. Achieving flow requires a more structured approach, and this is where the Takt Production System comes into play.

How to Achieve Flow with the Takt Production System

The Takt Production System doesn’t rely on a time-by-deliverable format, which can lead to confusion and inefficiencies. Instead, it organizes work based on a time-by-location approach. Imagine your project site as a series of zones—let’s call them Zone 1, Zone 2, and so on. Alongside this, you have time increments at the top. 

The goal is to see trades flowing smoothly through each zone in a diagonal, uninterrupted rhythm. This is how flow should look, and it mirrors the station-based production flow used by companies like Toyota.

Instead of relying on a CPM schedule that leads to inefficiencies, the Takt Production System organizes space to accommodate flow units, ensuring work progresses smoothly from one zone to the next. This method results in a streamlined, predictable process that maintains flow throughout the project.

Disadvantages of Using a CPM Schedule

While some people still advocate for CPM schedules, there are significant drawbacks. CPM often narrows the overall project duration while increasing work in progress beyond the capacity of the system. 

This only extends the project timeline. Earned Value Management (EVM) can further exacerbate the issue by incentivizing early spending, creating the illusion of progress while increasing work in process and adding unnecessary complexity.

Common Misconceptions When Handling Too Much Work in Progress

One common misconception in construction is that pushing harder—through overtime, adding more labor, or increasing materials—will result in faster progress. But this approach is like asking a group of kids to clean a room and, when they don’t work fast enough, adding even more kids. The result is more chaos, not more productivity. Similarly, in construction, adding more crews, materials, or overtime doesn’t help; it hinders flow.

3 Ways to Achieve Flow in a Construction Project

1. Level Your Zones: When moving from one zone to another, ensure each zone has a similar amount of work. This prevents bottlenecks and ensures smooth transitions between zones.
2. Level Your Trades: Make sure the crews working in each zone are leveled, meaning they take about the same amount of time in each zone. This keeps the work flowing consistently from zone to zone.
3. Have the Right Number of Zones: Having too few or too many zones can disrupt flow. The number of zones should align with the project’s scope and the available labor force to ensure a steady pace.

How Bottlenecks Are Created

If the zones in your project are not properly leveled in terms of work density, bottlenecks will form, causing delays and disruptions. For example, if one zone has more work than the others, trades will pile up and get stuck, hindering overall progress. Leveling the zones is critical to ensuring that trades can move seamlessly from one zone to the next.

How to Level Your Zones and Trades

Let’s revisit the importance of leveling. If the zones are adjusted to have an equal amount of work, and the trades are leveled to move at the same speed through each zone, the project will flow much more smoothly. This method eliminates bottlenecks and keeps the project on track. It’s essential to balance the workload and maintain a steady rhythm across zones and trades.

How Achieving Flow Can Shorten the Duration of Your Project

By leveling zones and trades and ensuring the right number of zones, you can significantly reduce the duration of your project. When work is properly distributed, and trades move efficiently through each zone, the project timeline is shortened, leading to faster completion and fewer delays. Using a Takt Time formula, you can calculate the exact duration of your project by adjusting the number of zones and keeping work consistent throughout.