A man hour, also called a person hour or labour hour, is the amount of work done by one person, such as an operative or tradesperson, in one hour.
Man hours are the standard unit for measuring labour input. A gang of four working an eight hour day uses 32 man hours, however the work is shared between them. Estimators use man hours to build up rates from labour constants or outputs, while planners use them to resource the programme and work out gang sizes and durations. For the QS, man hours are useful for:
- checking that a tender or subcontract quotation includes a realistic amount of labour;
- valuing daywork, where hours are recorded on signed daywork sheets;
- comparing planned and actual hours to assess productivity and disruption.
Related terms: Man Hour Rate, Labour Constant, Daywork, Output Rate.
