1. Why a project starts with the register
Three reasons make the order mandatory rather than advisable. The register is the starting point of the procedure.
| Reason | Consequence |
|---|---|
| The register states what the building officially is | not what can be seen on the plot |
| The content of the application depends on that position | the same work may require a different procedure |
| Correcting data takes time | it cannot be done in parallel with building |
Before commissioning a design, therefore, one must look at what data already exist for the plot or the building. Starting from this step is not caution but sequence: the third row explains why correcting after the fact costs more than checking beforehand.
2. What the register holds
The national building register consolidates data on all buildings and is accessible through a public view. That public character is substantive rather than formal here: it is not only the local authority that relies on the register, but also banks and buyers.
| Content group | What it contains |
|---|---|
| Existing buildings | intended use and volumes |
| Permits and notices | permits issued, notices submitted |
| Documents | entered in the register during procedures |
The register is therefore not an archive but the official position of a building. Third parties rely on it, as covered by the article on the cost of a building without documents.
3. What happens when the data are wrong
Four consequences appear at different moments, which is why they are not noticed together. They range from the procedure to a sale.
| When | What happens |
|---|---|
| During a procedure | the authority works from the register, wrong base data lead to the wrong procedure |
| In design | the design rests on the existing situation, whose description sits in the register |
| On sale | the buyer and the bank check the register, a divergence raises questions |
| When applying for a loan | the bank may not lend where the documents are not in order |
The fourth row is the most tangible and it affects those who buy rather than build. A wrong register entry is therefore not only the builder's problem: it carries forward to every subsequent owner until someone corrects it.
4. Three frequent discrepancies
These occur on plots managed in perfectly good faith, so their presence is not a sign of negligence. A discrepancy does not always mean a breach.
| Discrepancy | Why it arises |
|---|---|
| The building is absent from the register entirely | an old structure that was never entered |
| Volume data do not match reality | the calculation methodology has changed over time |
| Works carried out are not reflected | they were done without a procedure |
The second is the most common and the mildest, because it follows from a change of methodology rather than from anyone's action. The third is the most serious, because such works are unauthorised and do not appear in the national register, and legalising them is a procedure in its own right.
5. The order in which to act
Four steps before design begins, in an order that cannot be swapped. Each step needs the result of the previous one.
Look at what data the register holds and whether they match reality. This is the only step that can be done in a day and that costs nothing but time.
Check whether every existing building has been entered. A shed or garage missing from the register becomes a problem only when something else is applied for.
Check the volume data, which are the most frequently inaccurate and which determine the extension percentage, and hence the applicable procedure.
Only then determine the procedure required. The fourth step depends on the first three and cannot be taken ahead of them, because wrong base data give a wrong answer even from a correctly read table.
Summary and four practical rules
A construction project starts from the building register, because the content of the application depends on the register's position and correcting data does not run in parallel with building. The register is the official position of a building, relied on by the local authority as well as by buyers and banks, which is why a wrong entry carries forward to every subsequent owner.
Four rules: look at the register before signing the design contract. Check whether every existing building has been entered. Check the volume data, which are the most frequently inaccurate. Determine the procedure only after those three steps, because wrong base data give a wrong answer even from a correctly read table.
This article offers professional orientation as at the date of verification. It does not replace the assessment of the local authority.