Comparative study of the Net-zero Whole Life Carbon of buildings using a case study and methods from different countries

Louise Van de Velde

Key information

Authors:

Louise Van de Velde (Louise Van de Velde)

Supervisors:

José Dinis Silvestre (José Dinis Silvestre); Marijke Steeman

Published in

June 12, 2025

Abstract

The building sector plays a crucial role in global greenhouse gas emissions, accounting for nearly 39 percent of total emissions. In response to the urgency of climate action, Whole Life Carbon Assessment (WLCA) has become an essential tool for quantifying both embodied and operational carbon throughout the entire life cycle of buildings. This thesis explores how Belgium, Portugal, France, and the Netherlands apply life cycle assessment and how their methods could be harmonised at the European level. A WLCA is performed on a case study comparing the four national methods, focusing on retrofit materials of a residential apartment in Lisbon. Applying the Portuguese energy demand to each national context shows the operational carbon impact is highest in the Netherlands and lowest in France. A 100% renewable energy scenario examining green electricity certificates proves most favourable for Belgium and France. Moreover, a rooftop solar panel scenario evaluates the impact of exported energy within the WLCA framework, resulting in substantial negative values in module D for Portugal, Belgium, and the Netherlands. In contrast, the low grid emission factor in France limits the benefits of exported renewable electricity. Additionally, the influence of biobased materials and carbonation of cement-based products is considered to explain the differences in results. Although biogenic carbon must be modelled under EN 15804+A2, its implementation varies across manufacturers and EPD programs. Carbonation is optional but can offer notable carbon reductions. This research lays the groundwork for aligning national WLCA methodologies, contributing to a more harmonised and transparent European approach.