This paper explores how long it takes to build an apartment. In our effort to answer the question, we concentrate on the inventory phase. The phase involves the completion of every apartment. It includes several trades, a significant number of tasks and a great deal of coordination, and spans from erecting the walls to installing and coupling of technical systems and to the finishing of kitchen, bathroom(s), doors and all surfaces. The paper is grounded in the research idea that to make construction more like manufacturing, we need to study it from a manufacturing viewpoint. Its starting point are the peculiarities of construction as emphasized by one-of-a-kind projects, site production, a temporary organization and intervention of regulatory authorities (Koskela 1992). While these particularities have played a fundamental role to understand the uniqueness of the construction building process, we argue in this paper to handle them with caution so that they do not hamper initiatives – and insights – based on the commonalities of the two types of production. In the paper, a preliminary analysis is carried out based on a housing project including 127 apartments, divided by four, four-to-six storey high blocks. Using the single apartment as the production unit, we outline certain assessments which we plan to test full-scale in a sizeable housing project including 342 apartments. The paper discusses the potential benefits of defining an apartment as the production unit, and how it may assist production knowing how long it takes to build an apartment. We conclude that to build an apartment in a more effective and less wasteful manner than today, we should think of it as more of a manufacturing than a construction process.
Production planning and control, theory