On-site activities are typically performed when the end-product is immovable once it has been assembled and/or due to weight and space constraints in the production and transportation system. It is primarily a customer order driven type of production with a high level of customization. However, some customer order driven and/or customization activities can, or should, be performed off-site, but these aspects are typically treated in isolation of each other. There is therefore a need to make a combined assessment of on-site activities, customer order driven production, and customization activities. The purpose of this paper is thus to develop a typology that provides a holistic view of on-site activities in relation to customer order driven and customization activities. A flow-based three-dimensional typology is developed to assess combinations of three dimensions: flow driver, flow differentiation, and flow location. The property of each dimension is determined using decoupling points. The typology represents how on-site activities impact the feasibility of customer order driven and customization activities. “On-site” is defined as pursuing activities at the site where the final delivery is made. The findings show that forecast driven activities are risky to perform on-site and these should instead be performed before delivery to the site (off-site). The typology is applied to three case companies to illustrate its applicability to building construction. Future studies should extend the typology application to other types of construction and ETO industries to enable benchmarking of site-based production to other contexts with similar challenges related to on-site/off-site production.