Quick Guide: Using Gantt Charts with Constraints

Together with dependencies, constraints determine how multiple tasks within a project must be sequenced and scheduled. A constraint specifies how a task must be scheduled in relation to a specific date or another task.

Imagine you’re planning a wedding that will take place on June 15th. You have one series of tasks – reserving a venue, choosing a caterer, sending out invitations – that must finish before that date, and another – writing thank you notes, going on your honeymoon – that must start after that date. That date, June 15th, is known as a constraint date and each of those tasks has a constraint type associated with it.

Constraints are present in schedules for all types of projects, be they big, small, personal, or professional. With Spreadsheet.com’s Gantt chart views, you can incorporate these constraints into your project schedule to ensure that tasks are scheduled properly.

Creating Constraints in Spreadsheet.com

Once you’ve created a Gantt view in your project workbook, you can assign constraints to tasks. To enable task constraints, you must add two columns – one with the Constraint type data type, another with the Constraint date data type – to your schedule worksheet.

In Gantt views, constraints are created and managed through two specialized data types

Spreadsheet.com supports eight industry-standard types of constraints found in most project management software. Learn more about each constraint type in our Help Center.

Once you’ve added these columns to your worksheet, you can assign constraints to each task. Set a constraint type (like Must Start On or Finish No Later Than) and a constraint date. As you continue to build out your task list, add dependencies, and reschedule tasks, Spreadsheet.com will abide by these constraints as other task dates change.

Constraints are displayed on the Gantt chart as dotted vertical lines (for flexible constraints) and solid vertical lines (for inflexible constraints) to the sides of taskbars.

Tasks with associated constraints will have dotted or solid vertical lines next to their taskbars on the Gantt chart

Managing Constraints in Spreadsheet.com

Once you’ve created task constraints, you can edit them by changing the appropriate values in your worksheet’s Constraint type and Constraint date column.

Edit constraints by changing the values in your worksheet's Constraint type and Constraint date columns

You can also edit constraints by dragging and dropping taskbars on the Gantt chart. When you drag and drop a successor task, it will take on the SNET constraint with a constraint date of the task’s new start date.

Edit constraints – and task dates – by dragging and dropping taskbars on the Gantt chart

Take caution when editing constraints, as changes to one task can have an effect on dates for other successor or predecessor tasks in your project.

Explore Gantt Views with Spreadsheet.com

Constraints are just one of the many powerful project management features available in Spreadsheet.com. Use dependencies in your project schedule to properly sequence tasks and ensure proper scheduling logic.

Add automations to Gantt views to automatically notify team members of upcoming or overdue tasks, or use Spreadsheet.com’s sharing and collaboration features to help make your project management workbooks the single source of truth for your entire project team.

Learn more about constraints in our Help Center, or get started today with one of the many ready-to-use project management templates in Spreadsheet.com’s Template Gallery.

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