Uncertainty analysis in embodied carbon assessments: What are the implications of its omission?

Embodied carbon assessments of buildings are not methodologically very different from the more well-known life cycle assessments (LCAs). In particular, the two also share the frequent lack of uncertainty analysis in many assessments produced by academics as well as practitioners. An assessment that omits uncertainty analysis generally results in a single, very definite numerical output which however embeds no information on the likelihood of that value being true. Similarly, in comparative studies, the assessment produces two values, and the main outcome is merely reduced to a higher/lower comparison in order to choose the alternative allegedly less detrimental to the environment.

The chapter will provide the reader with a worked example through an overview of the whole process related to uncertainty analysis, from the rationale to the methodological challenges through to the increased usefulness of the results in comparison with single-value assessments. Addressing uncertainty and variability in LCA adds information about the significance and robustness of the results, as well as it benefits and facilitates environmentally conscious decisions by recognizing innovation opportunities that can be overlooked when not addressing uncertainty.