RICS Whole Life Carbon Assessment (WLCA)

The RICS Whole Life Carbon Assessment (WLCA) standard is a professional standard published by the Royal Institution of Chartered Surveyors that sets out a consistent method for measuring and reporting the carbon emissions of buildings and infrastructure over their entire life cycle. It covers upfront (embodied) carbon in materials and construction, operational carbon in use, and, uniquely, “user carbon” associated with how people use the asset.

First issued in 2017 and updated in a much-expanded 2nd edition in 2023–24, the WLCA standard responds to the fact that the built environment is responsible for a large share of global greenhouse gas emissions. It exists to provide practitioners with a single, transparent, and globally applicable methodology so that whole life carbon assessments are comparable between projects and robust enough to support regulation, targets (e.g. net-zero building standards), and client decision-making.

Methodologically, WLCA is not a “standalone” invention. It is explicitly built on the European building LCA framework in EN 15978 and related standards such as EN 15643, EN 15804 and EN 17472, but adds detailed practical guidance on data sources, assumptions and reporting rules, especially for the UK context. In effect, EN 15978 defines what needs to be assessed and at what system boundaries, while RICS WLCA defines how industry should actually carry out those calculations on real projects in a consistent manner.

Because of this relationship, WLCA is often used as the “go-to” implementation manual for EN 15978 in the UK and increasingly internationally. It operationalises the EN 15978 life-cycle modules and indicators into a practitioner-friendly process that can be embedded in design, cost planning and asset management workflows, and aligned with other frameworks such as ICMS3 and emerging net-zero carbon building standards.