Carpenters’ workday: Between value-adding work and physical strain

Productivity improvement efforts in construction often rely on Work Sampling (WS) to increase Direct Work (DW) and reduce Wasted Work (WW). Such time-based metrics rarely account for how shifts in activity change workers’ physical workload. This study examines the descriptive relationship between work categories and observed physical workload in a carpentry team on a Norwegian project. Over five workdays, a dual-coding WS protocol recorded activity type (DW, Indirect Work (IW), WW) and workload. Overall, DW accounted for 41.31% of observations, IW 47.89%, and WW 10.80%. Workload was predominantly Moderate (45.79%), with substantial shares in High (29.39%) and Low (24.83%). Descriptive linear fits showed a positive association between DW and High workload shares (R² = 0.28), and an inverse association between WW and High workload shares (R² = 0.36). Daily questionnaires indicated mental load peaked on the day with the highest WW, linked to organisational challenges. Findings suggest efforts to increase DW may create a denser physical workload profile for carpenters, requiring parallel ergonomic and work structuring measures.