Existing and unauthorised buildings

According to guidance published by local authorities, the question divides into four periods whose boundaries follow the periods of validity of successive laws. Each period follows its own rules.

Construction date	Requirement
Before 22.07.1995	deemed lawful automatically
22.07.1995 to 31.12.2002	must meet safety requirements, assessed against the requirements in force at the time of construction
01.01.2003 to 30.06.2015	safety requirements plus conformity with the detailed and comprehensive plan or with design conditions
From 01.07.2015	legalisation under the Building Code in force

The second row contains a significant relief that often goes unnoticed: safety is assessed not against today's requirements but against those in force at the time of construction. A building erected in 1998 is therefore not required to meet 2026 fire safety standards.

Three reasons explain why the date weighs more than the building's properties. The applicable law follows from when it was built.

Requirements have changed over time, and an old building cannot be required to conform to later ones. Each period in the table above corresponds to the period of validity of one law, which explains the choice of dates.

Evidencing the construction date therefore becomes the first task, ahead of technical assessment. The practical consequence is counter-intuitive: a document evidencing when the building was erected can be worth more than a technical survey, because it determines which set of requirements applies at all.

The Building Code amendments entered into force on 1 August 2026 and affect legalisation in three places. Their reach must be checked case by case.

Change	Effect
Buildings erected before 22.07.1995 are deemed lawful automatically	the burden of proof falls away
Safety is the precondition for legalising buildings erected before 01.07.2015	the focus shifts from the document to the condition
The €500 state fee for entering an unauthorised building in the register is abolished	the most tangible change financially

According to institutional sources, entering buildings that lack a legal basis into the register becomes clearer and fairer, giving owners the opportunity to record their buildings properly. For owners of old buildings the third row is the most direct: with the fee gone, the decision to start the procedure becomes cheaper.

This is the most important distinction in the article, and it is frequently lost. A building being deemed lawful does not mean it is in the building register.

According to professional sources this does not make legalisation optional, and a building that is not entered in the register remains not entered. The register entry is a separate act, requiring a data submission notice and technical data.

The consequences for sale and lending follow from the register, not from lawfulness, as covered by the article on the cost of a building without documents. The change therefore eases the route into the register rather than replacing it: the bank looks at the entry, not at the legal status.

Legalisation requirements depend on the construction date, which divides into four periods from 22 July 1995 onwards, each corresponding to the period of validity of one law. In the intermediate periods safety is assessed against the requirements in force at the time of construction rather than today's. On 1 August 2026 buildings erected before 1995 became lawful automatically and the €500 state fee was abolished.

Four rules: establish the construction date before any technical assessment. Look for a document evidencing that date, which is often worth more than a survey. Do not read lawfulness as a register entry, since the consequences for a sale follow from the register. Use the abolition of the fee as the occasion to resolve an old case.