Takt Steering & Control

Takt Steering and Control: Constraints vs. Roadblocks

Here’s the difference most people get wrong: constraints are part of the system design. Roadblocks are temporary blockers. You steer around constraints. You remove roadblocks. And knowing the difference transforms how you manage the train of trades. Because when you confuse constraints and roadblocks, you waste time trying to remove something that’s permanent. Or you build systems around something temporary. And that creates chaos.

Let me show you the difference and how to manage both.

The Pain of Confusing Constraints and Roadblocks

Here’s what happens when you confuse constraints and roadblocks. You try to remove a constraint. You can’t. It’s permanent or semi-permanent. You waste time. You frustrate the team. And the problem doesn’t go away. Or you try to optimize a roadblock. You build a system around it. You create workarounds. And then the roadblock disappears. And now you’ve overbuilt the system. The key is knowing which is which. Because if you treat a constraint like a roadblock, you’ll waste time trying to remove something that’s permanent. And if you treat a roadblock like a constraint, you’ll optimize around something temporary instead of just removing it.

What Are Constraints?

Constraints are part of the system design. From the time you start planning all the way to the end of the pull plan is where you’ll mainly find and optimize constraints. You can’t remove them entirely because they’re permanent or semi-permanent.

Here are constraint examples:

• Misjudged Takt Time or Packaging: The Takt time is too short or too long. The work packages aren’t sized right. You optimize it in the pull plan.
• Uneven Train Speeds: Too many varying speeds among the trades. It’s becoming a bottleneck. You optimize by adjusting the sequence or the Takt time.
• Resource Shortages or Missing Buffers: You don’t have enough crews. You don’t have buffers. You optimize by adding crews or creating buffers in the plan.
• Poor Zone Configuration: The zones are too big or too small or oddly shaped. You optimize by re-zoning.
• Things That Affect the Train of Trades: Anything structural to the system that you must work around.

The key insight most constraints should be figured out in pre-construction or at least by the end of the pull plan. Look at how many of these the root cause of why that constraint is not optimized in the first place is because of the pull plan. By the time the pull plan is done, we must have identified these and optimized them as much as we possibly can.

You can mark constraints with orange magnets on your visual boards. And this is important because every pace-setting train of trades in a phase will likely have a pace-setting trade bottleneck and a pace-setting zone bottleneck. Everything should subordinate to those bottlenecks to help them because those are your pace setters.

What Are Roadblocks?

Roadblocks are temporary. These are things in the way of the train of trades. These are things that can be removed. Weather maybe not, but you can remove the water or the rain or the snow from the weather. Changes to the plan, you can make sure that there’s stability through planning. Work area not ready, you can make it ready. Missing information, you can go get it. Defects, you can get rid of them.

So all of these are temporary. These are things that are in the way of the train of trades. And I want to make the point that last planners primarily focus on these. Everything after the pull plan is mainly roadblocks.

Here are roadblock examples:

• Weather delays or plan changes: Temporary. You can mitigate weather impacts and stabilize the plan through better planning.
• Incomplete site prep, permissions, or layout: Temporary. You can make the work area ready, get the permits, finish the layout.
• Defects, inspection failures, or material shortages: Temporary. You can fix defects, pass inspections, expedite materials.
• Labor or equipment issues: Temporary. You can bring in crews, rent equipment, solve the problem.
• Things in the way of the train of trades: Temporary blockers. Remove them.

You can see how many of these depend on the foreman huddle and the trade partner weekly tactical and lookahead planning. This all comes down to preparation. We steer the train of trades around constraints, but we remove roadblocks out ahead.

How to Make Work Ready (How We Find Roadblocks)

How we find roadblocks is by making work ready. In order for a crew to go do their work properly, they need to have all of these things, especially the materials, the equipment, the tools, the toolkit, and the information, permissions, and layout. Especially that in the space. It’s typically when a trade partner is making work ready that we find constraints and roadblocks. The zone boundary that this current crew is in is literally the focus for production for that crew. So this crew is working in this zone for their work package. But what’s interesting is they have work that’s being completed behind them and work that needs to be completed out ahead.

So now we have this pattern of “let’s go ahead and finish as we go within that zone and let’s prepare out ahead.” And the zone managers can literally come out and help manage the handoff, make sure that that crew is going to finish that zone on time, not by pushing people, but by literally making sure that everything is clear out ahead and everything is being punched as we go. And literally focus on: Is the handoff on track? Are we going the right speed? Do you have enough prep? Are you finishing as you go? Are there any roadblocks in the way? And if there are, what are the root causes?

Delay Management Strategies (How to Solve Constraints and Roadblocks)

Here’s what you should do when delays happen. You need to know what to do about these in a production-minded way so that you don’t hurt production. Here’s what you shouldn’t do: Never just add labor. Never just start working overtime. Never just throw money at the problem. Never rush, push, and panic. Never bring out all the materials too soon.

Here’s what you should do delay management strategies:

• Utilize buffers: If there’s a delay, you can eat into or utilize buffers and literally make sure that you maintain trade flow.
• Sequence delay: If you’re green, blue, orange, purple, and if the materials are ready and it works, and they’re not dependent in some unique way, you can switch the blue and the orange to where it’s green, orange, blue, purple. This is available a lot more than you think.
• Isolated delays: Where literally it’s just one boxcar, one area. So maybe you isolate the boxcar of the task or you isolate the area. At the bioscience research laboratory we had lab researchers that were changing the building at the end but we still had to finish. About 30% of the building was sustaining changes and this is the solution we used the most.
• Employ workable backlog: You have trained and onboarded workers that can come in and help with a second crew. This does not work when it’s a random crew that’s not trained and onboarded, but if they’re on the project as workable backlog, trained and onboarded, it does increase your capacity.
• Re-zone past the delay: Because we all know that going to smaller batch sizes will speed things up.

The bottom line is when you implement any of these, you need to consider the rules of flow triage: Are you prioritizing the work? Are we eliminating bad multitasking by focusing? Are you making sure that whatever you’re doing, you have full kit? Are you segregating work? Are you standardizing processes? Are you synchronizing to Takt time? And do you have buffers? If your project needs superintendent coaching, project support, or leadership development, Elevate Construction can help your field teams stabilize, schedule, and flow.

A Challenge for Project Teams

Here’s what I want you to do this week. When you see a problem on the job site, ask: Is this a constraint or a roadblock? If it’s permanent or semi-permanent, it’s a constraint. Optimize it. Work around it. If it’s temporary, it’s a roadblock. Remove it. Mark constraints with orange magnets. Mark roadblocks with red magnets. Use the problem-solving frameworks. Follow the delay management strategies. Follow the rules of flow. And steer around constraints while removing roadblocks. As we say at Elevate, constraints are system design issues you optimize. Roadblocks are temporary blockers you remove. Steer around constraints. Remove roadblocks. That’s how you maintain flow.

On we go.

Frequently Asked Questions

What’s the difference between constraints and roadblocks?

Constraints are permanent or semi-permanent system design issues you must optimize and work around. Roadblocks are temporary blockers you can remove. Constraints are found in pre-construction and pull planning. Roadblocks are found after the pull plan.

How do you find constraints?

By making work ready and by doing the pull plan. Most constraints are identified by the end of the pull plan. They’re your most limiting factors misjudged Takt time, uneven train speeds, resource shortages, poor zone configuration.

How do you find roadblocks?

By making work ready and asking daily trigger questions. Use red magnets on visual boards to mark roadblocks. The trades identify them when they’re preparing the work and discover something’s missing or in the way.

What are delay management strategies?

Utilize buffers, sequence delay (swap trade order), isolated delays (isolate one area), employ workable backlog (trained second crew), re-zone past the delay (smaller batches speed things up). Never just add labor, work overtime, or rush.

Why do you mark constraints orange and roadblocks red?

Because orange marks your pace-setting trade bottleneck and zone bottleneck. Everything should subordinate to help them. Red marks temporary roadblocks that must be removed. The color coding helps meetings focus on the right problems.