Eigenfertigung und/oder Fremdbezug in Produktionsunternehmen anhand einer Fallstudie der Banner GmbH

Abstract

The increasing automation of industrial processes has fundamentally changed the cost structure in companies and significantly increased the proportion of indirect fixed costs. Conventional cost accounting systems are reaching their limits as they often only allocate overhead costs on a flat-rate basis and do not adequately reflect their actual causation. This leads to distortions in the calculation and makes well-founded decisions more difficult, especially when it comes to strategic issues such as make-or-buy analyses. Against this background, more precise and cause-based cost accounting is a key prerequisite for economically business decisions. The objective of this thesis was to develop a practical and scientifically sound cost accounting system for battery box production at Banner GmbH. The focus was on the appropriate distribution of overhead costs as well as the development of a cost model for transparent product calculation and support of well-founded make-or-buy decisions. The basis for this was a comprehensive analysis of theoretical cost accounting approaches with a focus on the allocation of increasingly higher indirect fixed costs. To identify possible optimization potential, the methodology developed by Banner GmbH was also compared with the cost accounting practices of two Austrian injection molding companies. The results show that cause-related cost accounting is becoming increasingly important against the background of rising indirect fixed costs in industrial production. The literature emphasizes the need for precise allocation of overhead costs and a high level of cost transparency, especially to provide sound support for strategic make-or-buy decisions. As part of the case study, a calculation model was developed at Banner GmbH that provides differentiated full and marginal cost rates and thus creates a reliable basis for decision-making. The comparison with two other Austrian injection molding companies confirmed the chosen methodology, offered insights into alternative approaches and revealed additional potential for optimizing cost accounting. The work shows how theoretical concepts of cost accounting can be implemented in practice and adapted to industrial requirements. The developed costing model supports a cost allocation based on causation and provides a sound basis for make-or-buy decisions. At the same time, it provides impulses for the further development of existing cost accounting systems and strengthens the link between theory and practice under changing economic conditions.

Date of Award	2025
Original language	German (Austria)
Supervisor	Peter Hofer (Supervisor)