Labour Productivity Calculator

How is labour productivity calculated?

Productivity shows how much work comes out for the effort put in. Effort is measured in labour hours: the number of workers times the hours worked. Productivity is quoted in two ways:

• Work per labour hour: v = quantity of work / labour hours. A larger number means a more productive crew.
• Labour hours per unit of work: a = labour hours / quantity of work. This is the form used in unit rate build ups. A smaller number means a more productive crew.

Each is the reciprocal of the other.

Example

Suppose a crew of four working 8 hours a day lays 120 m² of blockwork in 3 days. The effort is 4 × 8 × 3 = 96 labour hours. Productivity is 120 / 96 = 1.25 m² per labour hour, so each square metre took 0.8 labour hours. The crew produced 40 m² a day, or 10 m² per worker per day.

Comparing with a target

If the bid assumed 1.5 m² per labour hour, the actual 1.25 is 83 percent of target. The same work at the target rate would have taken 80 labour hours, so 16 extra hours were spent. Multiplying that variance by the hourly rate gives the labour cost overrun.

Limits

Productivity changes with the difficulty of the work, weather, material flow and crew experience. A single day can mislead, so look at the average over several days. The tool does not use a published table of rates, you enter the target yourself.