Tracking labour productivity with installed quantities
The timesheets show 550 hours booked to wall framing on a block of townhouses, and the foreman says the crew is about on track. Nobody has counted how many metres of wall are standing. Until someone does, "on track" is an opinion.
Hours on their own say what was spent, not what it bought. Productivity needs two numbers for the same activity and period: the labour hours and the quantity installed. Estimators commonly express it as hours per unit — per metre of wall, per square metre of board, per tonne of rebar — where a lower number is better, so tracking the unit the estimate used lets you compare the two directly.
Setting up the measure
- Pick three or four activities that carry most of the labour budget, and use the unit the estimate used for each.
- Write a counting rule for each: what counts as installed — wall plumbed and braced, board hung and fastened — rather than delivered or started.
- Record hours by activity every day, only for the workers doing that work, under a cost code the crew understands.
- Count installed quantities on the same day each week, from a marked-up drawing or by measuring.
- Calculate two rates: this week's hours per unit and the to-date average. Compare the to-date rate with the estimate.
- Turn the gap into hours: installed quantity times the estimate rate gives the hours earned; the difference from hours spent is what the job has gained or lost so far.
- Go over the numbers with the foreman on Monday, while the crew can still act on them.
Common mistakes
- Counting material delivered or distributed instead of work installed.
- Dividing a crew's total hours by one activity's quantity when the crew also did other work.
- Reacting to a single week instead of the to-date trend.
- Changing the unit or the counting rule partway through the job.
Action list
Start this week
- Choose the three or four largest labour activities
- Write each one's unit and counting rule on one line
- Record hours by activity every day
- Count installed quantities every Friday
- Calculate the weekly and to-date rates
- Convert the gap from the estimate into hours
- Share the numbers with the foreman on Monday
Check your understanding
A crew's rate this week matches the estimate, but its to-date rate is 25% worse. Is the activity back on budget?
Show the answer
No. This week's rate shows the crew can now work at the estimated pace, so the remaining work may cost what was planned. The hours already lost stay lost and belong in the forecast. If another party caused them and you recorded it, raise them as a change on a line of their own; do not leave them out.
