Offshore construction yards are under pressure to improve cost-efficiency and productivity, as they transition from oil and gas projects to new renewable energy markets such as offshore wind. These emerging markets are characterized by tighter margins, increased risk, and higher volumes of equipment, which in turn place greater demands on internal logistics and material handling. A key challenge is the management of on-site storage, where high inventory levels can lead to congestion, inefficiencies, and delays. This paper investigates the underlying factors that affect storage space management through elevating storage needs or limiting storage capacity at offshore construction yards. Using a qualitative single-case study approach, we analyze data from a Norwegian offshore construction yard collected through interviews and a validation workshop. The findings identify eight main factors, spanning supplier collaboration, planning practices, project execution, and internal coordination. The study proposes targeted strategies to reduce on-site storage, including revised planning parameters, improved supplier interfaces, project differentiation, and enhanced cross-functional coordination. A conceptual model is developed to visualize the relationships between these factors, their consequences, and proposed interventions. The paper contributes to a better understanding of logistics challenges in complex engineer-to-order environments and offers recommendations for offshore yards seeking to improve material flow and reduce inventory-related constraints.