Gantt charts are a powerful way to visualize your timeline and see how each task affects others. They’re also a great way to identify bottlenecks, overallocations, and anything else that is likely to delay the completion of a project.

Unfortunately, once you’ve created a Gantt chart, testing alternative timelines can be difficult. What kind of impact would it have if you gave Team A just a little more time on that critical task? You could adjust the task’s End Date, see how it affects your timeline, and then adjust it back — but what if you wanted to test several changes to see which one offers the best result?

Is it better to give that task more time or adjust the resources available to work on it? You could create several different charts — if you have that kind of time and whatever Gantt solution you’re using allows it. Or you could test each variation one at a time, carefully tracking every change and hoping you don’t forget anything when you revert them all back to your original timeline…yikes!

You get the idea. Testing changes to a Gantt chart has long been more work than it’s worth. Until now.

Introducing Sandbox mode for Structure.Gantt

Sandbox mode, which arrives in Structure.Gantt 3.0 (the on-prem editions only, for now), makes it easy to test and compare changes to your timeline, resources, and other elements of your project plan.

Let’s revisit the situation we talked about above. You’ve created a Gantt chart. Management loves the timeline, but Team A is under some serious pressure to get their work done. Maybe they're even overallocated. Structure.Gantt already had a solution for this: Resource Leveling can automatically adjust tasks to alleviate overallocation. Which is great for Team A, but management might not be happy about how those changes affect the timeline. Maybe you could convince them to give Team A more resources…

Test and compare multiple changes

Using Sandbox mode, it’s possible to test a variety of changes — as many as you like — and compare them all to the original chart and to each other.

Let’s see how it works.

Step 1: Open the live chart

Open Structure.Gantt with your existing chart.

Step 2: Create your first sandbox

Open Sandbox mode and create a new sandbox. Let’s call this one Resource Leveling Test.

Once you’ve created the new sandbox, run Resource Leveling. This will automatically fix any overallocations. It’s probably going to push back your timeline, but don’t worry, this is just a test.

If Team A isn’t actually overallocated, that’s OK too. Instead of using Resource Leveling, just manually adjust those tasks you feel they’re going to need more time on.

Once you're finished, close this sandbox. Don’t worry about how it affected your timeline just yet — we’ll come back to it.

Step 3: Create a second sandbox.

Let’s call this "Help for Team A."

This time around, open the Resource Panel and adjust the resource units for Team A. Give them an additional person — or more, if you think management will go for it.

Once you’re done, go ahead and close this sandbox too.

Step 4: Compare your results

Now we get to see which option works better.

Go back to your Resource Leveling sandbox. While still in Sandbox mode, go to the Baselines menu and select Original Schedule. This will place the live timeline over top of your test timeline, so you can see not only how much your changes will impact the timeline, but exactly how and when those impacts are likely to occur.

You can do the same thing with your second sandbox. Or compare both sandboxes — the other sandbox should also be available from the Baselines menu. Now you can easily see both test options side by side — and have hard data to justify adding those additional resources to Team A!

Test whatever you like

Maybe there are other tests you’d like to perform, or other scenarios management wants you to try. Go ahead. You can adjust several factors in a single sandbox, do one sandbox for each type of change, or whatever works best for you.

Sandbox mode allows you to test a variety of changes to your Gantt timeline. For example, you can:

• Move individual tasks across the timeline, or adjust their start or finish dates.
• Switch a task from manual scheduling to automatic scheduling, or vice versa.
• Change the duration of a task.
• Move tasks from one sprint to another.
• Assign a new resource to a task, or adjust how much work a resource can do.
• Adjust a resource's units, time zone, work calendar, or availability.
• Run Resource Leveling.

Make your changes live

After you’ve tested changes, you may want to apply some of them to your live chart.

Once again, we’ve made that as simple as possible. Just click the Merge Sandbox button. You can apply every change from a sandbox, or handpick just those changes that will make the biggest difference to your project — or put the biggest smiles on management’s faces.

What next?

If you don't have Structure.Gantt yet, download an evaluation to see how it works. If you're already a Structure.Gantt customer, our release notes will have in-depth details on the feature.

As always, anyone can contact ALM Works' support team for help.

Have fun playing in the Sandbox!