To make the EPCs more reliable, particular attention must be paid to the reliability of the data that allows the evaluation of the key performance indicators.
These building characterisation data concern the intrinsic characteristics of the various envelope components and HVAC systems; they are qualified and quantified mainly during the on-site inspection of the building and according to some information and documents that can be obtained and consulted before the visit.
For existing buildings, assessors face the crucial problem of the difficulty of collecting reliable data without resorting to extensive, long, and costly investigations.
Indeed, the assessor only has a short time for the building inspection, so it is essential that he can rely on a structured protocol that allows reliable data and information to be collected.
From these observations, the EPC RECAST project has defined a European and harmonized protocol as a “Data Model” to describe the building and has developed and integrated enrichment and verification methods into this protocol and linked this protocol to existing technical components to facilitate and make the data collected more reliable.
This report details the EPC RECAST Data Model, based on a generic building description, ensuring that the structure and data model could be efficiently used by assessors while addressing a detailed calculation method after conversion.
In the EPC RECAST Data Model, different data collection possibilities have been proposed for each component to consider the diversity of situations, from the complete lack of information to the most specific case according to technical documents, allowing a precise characterisation of the component.
It has been considered that certain input data of the Member States’ calculation methods have defined standard values which depend on certain parameters and criteria. These parameters are integrated into the Data Model because they should be able to be collected to allocate typical values to certain calculation input data.
An accuracy rating has been assigned to each type of data collection ranging from 1 to 5. This method allows the assessor to use the most precise method according to the different choices offered to him and promotes the collection of detailed information.
This data model is implemented in an Excel file. It was produced based on previous considerations and the French EPC’s experience. It was enriched and completed to integrate the contributions of other partners in relation to the practices of their countries and the specificities of the calculation methods they use.