The draft of the new HSA 1 section of the CTE will require the declaration of the Global Warming Potential of the building in kg of CO₂ equivalent per square metre of useful area, in new construction and extensions. The calculation covers the modules of product (A1-A3), construction process (A4-A5), maintenance and replacement (B1, B2, B4), operational energy (B6) and end of life (C1-C4).

A technical detail with practical consequences: the regulations provide for a corrective factor depending on the quality of the data. If specific data from an Environmental Product Declaration is used, the calculation is more favourable than if generic database values are used. In other words, working with materials that have DAP not only improves transparency, but also refines the result of the regulatory calculation.

For material manufacturers, this reinforces the incentive to have verified DAPs. For engineering and construction companies, it means integrating the carbon calculation as one more verification of the project, along with the energy requirements that the CTE already contemplates.