Download any free construction schedule template and you get the same thing: a task list, durations, start and finish dates, and a bar chart. What you almost never get is a column for how many people each task needs, and a row underneath that adds them up. Which is odd, because on a real job the binding constraint is rarely the calendar. It is that there are three electricians.
I built one with that row in it. It is free, it is a normal Excel file, and this is what the extra column changes.
What the usual template gives you
The typical construction schedule template is a date recorder. You type a start date, you type a duration, a conditional-formatting rule paints the bar, and the file renders what you decided. It is a tidy way to present a plan and a poor way to test one, because it cannot disagree with you. Push a date and the chart accepts it. Overlap five trades in one week and the chart accepts that too.
The better ones calculate. Start comes out of the predecessors rather than out of your head, weekends are skipped, and moving excavation four days moves everything downstream with it. That is a genuine improvement and it is where most templates stop.
Stopping there means the schedule still has no idea how many bodies it is asking for.
The two columns and the row
The addition is small. Each task gets a Resource — Crew, Electrician, Excavator, whatever you actually count — and a number for how many of that resource it needs per day. Underneath the day grid, a panel sums, for every date in the schedule, the demand from every task in progress on that date. Next to it sits what you have available. The cell turns red when demand exceeds it.
Two columns, one conditional format, and the chart acquires the ability to contradict you. That is the whole trick, and it is the reason this construction schedule template is worth swapping for whichever one you are using.
What it looks like on a real plan
The sample in the file is a twenty-one task renovation running from early September to the start of December — slab, framing, roofing, windows, rough-in, drywall, and a parallel exterior stream of painting, driveway and landscaping. It is precedence-clean. No task asks for more than three people. Every date is defensible on its own.
The load panel is red for fourteen days, and peaks at five people against a crew of three.
Nothing about that is visible in the bar chart. The bars are correct. Each individual task is staffed sensibly. The overload is an emergent property of five tasks overlapping in the same fortnight, and there is no view in a normal Gantt chart that shows it to you. You find it on site, in the second week of October, when two things need the same crew and one of them does not happen.
Solve the same plan against the crew you actually have and the finish moves from 25 November to 2 December — five working days later — and eleven of the twenty-one tasks shift. That gap between the critical-path date and the real date is what the crew column buys you. You can see it in August instead of finding it in October.
Float is not what the critical path says it is
This is the part that surprised me, and it is the strongest argument for counting crew rather than only dates.
Classic critical path method assumes unlimited resources. Run it on the sample and roofing comes out with nine days of float — plenty of room, not a worry, slide it if you need to. Run it again with the crew hand-offs included, so that a task cannot start until the people it needs have finished what they were doing, and roofing’s float is zero. It is not waiting on a dependency. It is waiting on the windows crew.
Twelve tasks are critical by CPM. Thirteen are critical once crew is accounted for, and it is not the same thirteen. It moves both ways, in fairness: a few tasks gain float, because the crew-limited finish is five working days later than the critical path assumed and there is more room in the real schedule than in the imaginary one. But the direction that costs you money is the one above. Any float number that came out of an unlimited-resource calculation is describing a project you are not running, and that is worth knowing before you promise somebody nine days of slack that does not exist.
Where the spreadsheet stops, and what the button in your software is doing
A spreadsheet can show you the red. It cannot clear it. Rearranging tasks so nothing exceeds the crew you have, while honouring every dependency and finishing as soon as possible, is a resource-constrained project scheduling problem, and it is NP-hard. Formulas do not reach it.
Neither does the Level Resources button, which is the thing worth knowing if you are paying for scheduling software. Those packages run a priority rule — a rule of thumb for deciding which task goes next when several compete — and hand you a schedule without telling you how close to the best one it is. The one serious benchmark of that behaviour, Kolisch’s 1999 study in Interfaces, ran 160 known-optimal problems through seven commercial packages and found a median result 3.57% above optimal — and, more to the point, results that got steadily worse as resources got scarcer. I went through those numbers in detail here. The short version is that the leveling button is least trustworthy precisely when you are short-handed, which is the only time you press it.
So the split I use: the spreadsheet holds the plan and shows the problem, and the solving happens in something that can actually solve. Upload the same file to the free project scheduler and a constraint solver answers one of two questions — work within my crew, when does it finish, or keep my date, how many people would that take — and writes the result back into the workbook, so your chart redraws itself and the red row clears. It also says whether it proved the answer optimal or merely found the best it could in the time it had, which is a distinction the commercial packages do not offer you.
It is the same idea as my free shift scheduler, pointed at a different question: that one decides who works when, this one decides what happens on which day.
Take the template
The file is free to download — no email, no signup, opens in Excel or Google Sheets. Sixty tasks, ninety-five days. Predecessors take the standard Primavera and MS Project notation, so 4FS+2 means start two working days after task 4 finishes, which is how you write “wait for the concrete” without inventing a fake task that shows up in your headcount.
Two caveats worth stating plainly. It assumes whole-day durations and five-day weeks unless you change the parameters tab, so if you run Saturdays, change it before you trust the dates. And it assumes a person is either on a task or not — no splitting one carpenter across two jobs at forty percent. If that is how your crews really work, the load panel will read high. The file is unlocked, on purpose.
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