Automate Timeline Based on Start Date Column and Duration

Hi, looking for help on this.
I have a board for a construction project. Each item represents tasks. I have Start Date, Duration, and I created End Date as a formula column. FORMAT_DATE(ADD_DAYS({Start Date},{DurationDays}))
But I want Timeline (for a Gantt chart) populated from Start Date + Duration. I only want to have to enter those two pieces of info (start date and duration).
I also have dependencies, where later tasks are dependent on prior tasks.

I have tried doing the add-in Start + End = Timeline, but it doesnt recognize my End Date column, I assume because it’s not a date column. And I have Timeline linked to Duration column., which is working. But Timeline isnt dynamic when I change the Start Date column.
Thanks in advance!

@OEScoast23, I think the simplest solution is to use the Timeline and Duration columns exclusively because you can do many of the basic automations using it. You could remove the need to use a formula column.

Are there any other considerations or reasons you’d need to use a date column for your end date?

Thanks for this! So what is that screen cap showing? Is that an integration? It sounds like what youre proposing would work, i just am lacking some knowhow.

Oh I see the automations, not an integration. And I see “When data arrives”, but where does the second half come from? How do I get timeline updated from that. Are you suggesting I need to use the app “Start + End = Timeline”?

Any suggestions on the Automation to use for this?

I want to do the same thing… Seems like basic project management

Hi @Elliottmb @OEScoast23 - you can use General Caster to achieve this.

Set up two integrations to trigger on change of Start Date and Duration (this way the timeline is changed whenever one of these columns is changed).

Then use the following formula for each (make sure you substitute your columns for what I have entered for Start and Duration):

CONCATENATE({item’s Start}, “+”, TEXT(DATEVALUE({item’s Start}) + {item’s Duration}, “YYYY-MM-DD”))

Hope this helps!

And what about someone changing the timeline columns. Will adjusting timeline affect the Start and Duration?

@geoffb You would need to have two additional formulas.

DATEVALUE(LEFT({item’s Timeline}, 10)) will set the start date on change to the timeline

DAYS(DATEVALUE(LEFT({item’s Timeline}, 10)), DATEVALUE(RIGHT({item’s Timeline}, 10))) will set the Duration. Exchange DAYS() for NETWORKDAYS() if you only want workdays and exclude weekends.

Hope this helps,

Actually, it’s not working…I am getting an error message, unexpected error occurred. I thought it was working because I had the timeline/duration linked and that was working.

Wondering if the formulas are off? Is the word “item’s” supposed to be included?

Sorry, I dont understand how to read more info on the error message. I see some hint of a longer message in the email notification, but there’s no actual message in the body of the email.

This isnt working at all. Thanks for any further insight you might have. I started a fresh board and just added in your first item above. I wish the error messages from Monday were more helpful. But yeah, just nothing’s working.

I have StartDate associated with a Dependent On column. Maybe that is initiating the error and other problems.

I’d love to have new eyes on this. I tried the general caster solution and it just creates “unexpected errors” and doesnt update anything on the board. Including a screen shot of my board. EndDate is a formula column that adds duration days to start date. I need Timeline to update automatically. And I have a dependencies column, start date changes with that.

Also, screen shot of my general caster integration.

I figured it all out. And it is working now. I got rid of EndDate column. I have StartDate, DurationDays (numeric column), and Timeline. I have timeline linked through the column settings to Duration Days. And then I have 3 General Caster Integrations with these formulas, each using the integration ’ When column changes, perform formula and cast result.
1-When StartDate Changes, Formula is CONCATENATE(TEXT(DATEVALUE({item’s StartDate}), “YYYY-MM-DD”), “+”, TEXT(DATEVALUE({item’s StartDate}) + {item’s DurationDays}-1, “YYYY-MM-DD”)) and cast result to Timeline
2-Repeat 1 but for DurationDays
3-When Timeline changes, formula is TEXT(DATEVALUE(LEFT({item’s Timeline}, 10)), “YYYY-MM-DD”) and cast result to StartDate

@OEScoast23 I am new to I tried to add the automation, but I am not sure how to enter the formula. Any help would be appreciated!

Did you get general caster? And you found the option that fits the above screen cap? When you click on FORMULA, just paste in what I have there from the word Concatenate through the last set of double parenthesis. See that?

@OEScoast23 I apologize for my ignorance, but I am not sure what “general caster” means or where to find it.

This solution requires an add-in app. If you click on the little puzzle piece icon (left side of screen) you can search the apps and add it in…you may have to be an account admin…my company has it set up that way. Anyway. I will warn you that I’m finding this solution above is going to require me to upgrade my account, usage of the app comes with a pricing structure that I wasnt fully clear on. I cant speak to how much the cost is