This paper presents a retrospective case study comparing a life cycle cost analysis performed ten years ago with the actual cost outcome between 2014–2023. It does so to exemplify and problematize the notion of uncertainty. Through an industrial case it gives recommendations to practitioners how to reduce it. By a quantitative cost follow-up and a qualitative focus group study with key representatives of the case company the paper sets out to code sources of uncertainties, and to categorize these into either epistemic/aleatoric and into internal/external. The paper contribution is a suggested framework on management of uncertainties in industrial LCC