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Display and certificate

📐 Article4 min read

What you will learn What the certificate is, the display obligation and its form, its decisive legal effect, and the errors that prolong exposure.

Display looks like a minor administrative formality. It is in fact the act that starts the appeal clock, which makes it one of the most important steps in the procedure.

What the certificate is

Where the permit is granted, the mayor issues a certificate attesting that the proposed construction has been the subject of their authorisation.

This certificate is not the permit itself, but the attestation intended to be brought to the public's notice.

It states that the public may inspect the plans belonging to the permit, at the municipal offices, during the period in which the permit is open to challenge.

Information about the issue is also published on the municipality's website.

Requirement What it imposes Consequence if missing
Content of the notice The particulars required by the text Start of the period open to challenge
Duration of display Maintained throughout the set period Appeal period not run out
Visibility from the public way A notice legible from outside Challenge possible

The display obligation and its form

Three requirements, all provided by law.

Display falls to the client, not to the municipality.

It is made at the site.

It must be visible and legible from the public highway by interested persons, which is a requirement of result rather than of effort.

Display placed so as not to be legible from the public highway therefore does not satisfy the obligation, with the consequences set out below.

Its decisive legal effect

This is the point to retain.

The appeal period runs from display.

So long as display has not been properly made, that period does not run usefully, and the permit remains open to challenge.

The intuitive reasoning must therefore be reversed. Deferring display so as not to attract attention prolongs the period during which a third party may act, instead of shortening it.

Displaying early, properly and durably is a measure of legal security, and probably the cheapest one on a project.

The errors that prolong exposure

Four errors, all observed in practice.

Not displaying, in the belief that neighbour difficulties will be avoided.

Displaying at a point not visible from the public highway, which legally comes to the same thing.

Using a support that does not last, illegible after a few weeks of weather.

Removing the display before the period expires, which weakens the demonstration that the formality was properly carried out.

Evidence of display is created at the same time as the display, by dated photographs and retention of the support.

What display does not do

Two useful clarifications.

It does not cure the permit's defects. An unlawful permit remains open to challenge during the period, whatever the quality of the display.

It does not authorise starting works where other permits are missing, covered in the article on other permits required.

What this means for a professional

Four rules.

Display immediately after issue, and remind the client of this in writing.

Check legibility from the public highway, on site rather than on plan.

Create evidence of display as soon as it is put up, by dated photographs.

Explain the effect of the mechanism to the client, whose instinct is often to stay discreet.

This article reflects the regulatory framework at the date of checking and serves professional orientation. It does not replace consultation of the municipality or legal advice.

Frequently asked questions

The decision, in the form and for the duration required by the text, visible from the public way. The obligation falls on the holder.

It starts the third-party appeal period running. Without proper display the period does not run and the permit stays exposed.

A late, incomplete, illegible or prematurely removed notice. All four occur in practice.

No, it merely starts the period. An unlawful permit remains challengeable under the conditions set by the texts.

The building permit in Luxembourg