Whole Life Costing is a financial estimation approach that identifies and estimates the life cycle costs of a project. This research attempts to highlight this methodology, which, although well known, tends to be overlooked in projects. The motivations behind this research are primarily practical. Whole Life Costing makes it possible to take into account the socio-environmental costs resulting from project externalities. Furthermore, the digital transition of the sector calls for improved control of construction costs thanks to the arrival of new information technologies. These technologies, led by Building Information Modeling (BIM), offer various more technological and more collaborative organizational capabilities that facilitate life cycle management. This is therefore an opportunity to bring the whole life costing approach back into the spotlight. From a theoretical point of view, it is essential to understand the persistent barriers that prevent its use. Next, it is necessary to understand the challenges of integrating technology into construction projects. The literature review identifies semantic web technologies as a solution for interoperability and integration. An ontology is a model for representing knowledge that can be interpreted by both humans and machines. The objective of this thesis is to explore the use of semantic technologies and BIM as tools to support the systematic integration of Whole Life Costing into estimation practices. The research project adopts the Design Science Research methodology. This methodological approach makes it possible to propose solutions to practical problems while confronting them in both the theoretical and application domains. Adopting a pragmatic stance, a mixed collection method was used to gather quantitative data through two surveys and qualitative data through semi-structured interviews and a focus group. The data were collected from construction estimators and economists, mainly located in Canada. The results are presented in this thesis in the form of three peer-reviewed papers. The first study clarifies the challenges of the approach and highlights the importance of its interpretative nature. It proposes that cost professionals take responsibility for Whole Life Costing, seen as an opportunity for professional evolution. The second paper contributes by translating knowledge, particularly from ISO 15686-5, into ontology. An initial demonstration in this paper presents the computational capacities based on ontology and discusses its potential uses. In the third paper, a semantic platform is developed to analyze project cost estimates. Ontology is used to model knowledge and calculate whole life costing, demonstrating the benefits of semantic technologies. The thesis discussions highlight the need to increase the use of whole life costing in projects and to integrate it into the responsibilities of cost engineers. Its adoption, however, will depend on a cultural and organizational shift allowing estimators and cost engineers to be trained and to bring added value to projects by optimizing financial decisions across economic, environmental, and social dimensions.
Yousfi, A. (Author),
Poirier (Supervisor) &
Forgues (Co-supervisor),
19 Feb 2026Student thesis: Doctoral thesis › Doctorate in Engineering: Engineering