The windows have been replaced, work has been done on the façade and now the house is to be sold. The existing energy performance certificate is still in the folder. Before you use its information in an advertisement, you should have it checked to determine which building condition it describes and whether it is still the decisive document.
First look at the certificate itself in full
Our editorial recommendation: Record the complete version, the date of issue and the unequivocal building allocation. A single page with a coloured scale is not sufficient for the check. Where there are several building parts it must be clarified which part is actually recorded. Also keep any existing calculation and issuance documents.
Decisive is § 79 of the Gebäudemodernisierungsgesetz (GModG), the previous Gebäudeenergiegesetz (GEG). § 79 generally describes energy performance certificates as building information and specifies a ten‑year period of validity. [ENERGIE] The date is therefore important, but not the only point to check.
Collect the works carried out with a time reference
Compile which works were actually carried out after the certificate was issued. Distinguish planning, commissioning and completion. Invoices can support the context; they do not replace every technical specification. A new window in the cellar and a comprehensive change to the building envelope should not disappear under the same vague heading of renovation.
Record whether there is an energy-technical calculation, a proof or already a newer certificate. An improved single component value is not automatically the new figure for the entire building. Therefore do not transfer a saving figure taken from a quotation into the property advertisement as if it were the confirmed overall value.
Link the validity technically to the current condition
§ 79 also provides for a premature loss of validity if, under § 80 paragraph 2, a new certificate becomes necessary. [ENERGIE] This does not mean that every minor repair automatically triggers a new certificate, nor that a still recent document is sufficient unchanged for every alteration. The concrete question must be answered on the basis of the scope of the measures and the relevant further provisions.
Give a suitably qualified expert the existing certificate and the associated alteration documents for assessment. Ask explicitly for the version that is decisive for the sale and which details may be adopted with evidence. This article does not replace a check of the statutory triggers in individual cases.
Example: Two versions without a clear connection
A seller finds an older certificate and a later calculation for a planned façade measure. At first it is unclear whether the measure was fully implemented and whether a new certificate resulted from it. She clarifies the status with the existing records, instead of simply choosing the more favourable figure from both documents.
Only then update the publication
Once the decisive version has been clarified, reproducibly adopt its information in the sales documents. Remove contradictory intermediate states from the intended publication set, but keep them separately for internal traceability. An energy performance certificate does not promise specific actual heating costs for every household. In the advertisement it should retain the same function as in its checked documents.