Work out construction labour requirement instantly with clear inputs, formula shown and shareable results.
Labour demand is total effort divided by available time. Effort in person days is the quantity divided by effective daily output, where effective output is the nominal norm reduced by a site efficiency factor covering weather, waiting and rework. Dividing by the programme duration gives the crew size.
Effort
Person days = quantity / (norm output x efficiency)
Crew size
Workers = ceil(person days / duration)
Person days = quantity / (norm output x efficiency). Labour demand is total effort divided by available time.
Rarely. Beyond a certain density workers interfere with each other and productivity per head falls, so crowding a trade usually gives less than proportional gain.
This calculator takes 4 inputs: Quantity of work, Output per person per day, Available duration, Site efficiency. The pre-filled defaults are a realistic worked example — replace them with your own site or project figures.