The application date governs

One sentence on which everything else depends. The application date governs the requirement.

According to information published by the Ministry of Climate, updated energy performance requirements apply to buildings whose building permit application or building notice is submitted from the date of entry into force, and where the document was submitted before that date, the earlier requirements apply. The date is therefore decisive.

What governs is therefore the submission of the application, not the start of construction or the occupancy permit. This is the same logic that applies in the building permit procedure itself.

Three reasons, whose combined effect is protection of work already done. The rule gives the project legal certainty.

A project does not become invalid mid-procedure if the requirements tighten in the meantime, and the calculation made during design remains valid once the application is submitted. Schedule risks therefore do not carry over into regulatory risks.

Without this rule, every delay would mean redoing the project, which would be disproportionate. The rule prevents continuous redesign.

An observation that saves concrete errors, and it concerns the 2025 changes specifically. Two regimes were running in parallel.

Source	Date	Status
Some published materials	1 March 2025	obsolete
Legislation in force	1 June 2025	in force

Materials naming 1 March date from before the amendment: they were not wrong when published, but they are now out of date. The practical rule is broader than this one case: check the date of entry into force against the legislation in force, not against explanatory materials, because dates of entry into force are amended and commentary does not always follow the text.

Three consequences, and the first should be said aloud rather than used tacitly. The applicable requirement belongs in the document.

The timing of submission is a regulatory decision, not merely an administrative one: where new requirements are known and imminent, timing affects which regime applies. If the project later runs late, the requirements do not change retroactively once the application is in.

Timing a submission around a change of requirements is legitimate where the project is genuinely ready. Submitting a half-finished project merely to catch a date is a risk, because an incomplete application is rejected and the date goes with it.

Three questions, the third of which needs the local authority's answer. The answer should be obtained in writing.

Question	Why
When the application was submitted	determines the applicable version
Which version of the regulation was in force then	determines the limit values and methodology
Whether the project has since been substantially changed	a substantial change may mean a new application

The third must be clarified with the local authority, because assessing it is not the applicant's call. Administrative practice differs between authorities.

Updated requirements apply to buildings whose building permit application or building notice is submitted from the date of entry into force, and earlier requirements apply to documents submitted before it. What governs is therefore the submission of the application rather than the start of construction or the occupancy permit, which protects design work already done against a tightening of requirements. One common error is dating the 2025 changes to 1 March: the date in force is 1 June 2025.

Four rules: record the application date in the project documentation. Check the date of entry into force against the legislation in force. Treat the timing of submission as a regulatory decision where requirements are changing. Do not submit an incomplete application to catch a date, since rejection loses the advantage.