Economic analysis and operational research tools for estimating productivity levels in off-site construction [Analisi economiche e strumenti di Ricerca Operativa per la stima dei livelli di produttività nell'edilizia off-site]

The building industry struggles with productive performances less and less significant. While other sectors have been able to take advantage from technical evolution, changing themselves and increasing their performances, the construction sector is stuck in the production levels of the 80s. In the building industry, half of the worked hours do not generate economic value. It is a shared opinion that the production hemorrhage of the sector can be stopped opting for a hybridization with the manufacturing sector. Nowadays, the synthesis of construction and manufacture is identified with the off-site building. It lowers the intensity of construction work in place by transferring them to the workshop, where components are made on the basis of economic principles that line up those of industrial production. The present analysis aims to estimate the productive contribution attributable to this strategic alternative. For this purpose, referring to three default building prototypes, an analytic protocol is developed for the extrapolation of economic data and of productivity indices. This protocol is implemented with the help of reticular programming techniques as PERT (Program Evaluation and Review Technique) and CPM (Critical Path Method). The results highlight the real chance, for the construction industry, to catch up with the production levels of the total economy.