Lean is about waste elimination and value creation and prefabrication of houses seems to be one way to create structure and decreased complexity and waste generated by variation. However, prefabrication decreases some types of complexity and waste but introduces other ones through new roles of the actors and a shift of focus to manufacturing. The aim of this paper is to develop an understanding of a prefabrication strategy and to show the increased need for a novel comprehension in lean construction regarding different types of prefabrication deliveries and thus different types of complexity. Complexity as such, in this paper used in a contingency context, cannot be generalized and this study explores the differences in peculiarities of on-site construction, element prefabrication and volume element prefabrication. Peculiarities in volume element prefabrication are found to consist of two connected parts; Product complexity including building element design and product design (built-in knowledge) and process complexity including internal logistics, breadth of required knowledge and integration between product and process design. The sources of complexity in volume element prefabrication are thus connected to the in-house production system, differing from on-site construction and element prefabrication peculiarities connected to fragmentation and uncertainty among actors in the value chain.
Volume element prefabrication, Building peculiarities, Product complexity, Process complexity,Timber frame housing