1. The ten-day rule
Two periods are the same length but mean different things, and confusing them is common. One concerns the procedure, the other the start of building.
| Period | Whose it is |
|---|---|
| The notice must be submitted at least 10 days before construction begins | the applicant's obligation |
| The authority has the statutory 10 days from submission to handle it | the authority's deadline |
If the local authority says nothing within ten days, construction may begin. Silence is therefore consent, which separates a notice from a permit in principle: with a notice one waits not for a decision but for a period to expire.
2. Validity extended
The change entered into force on 1 August 2026 and directly affects projects that run late. Its reach must be checked case by case.
| Period | Validity |
|---|---|
| Before 01.08.2026 | 2 years from submission or approval of the notice |
| From 01.08.2026 | 4 years |
The practical effect is that where construction is delayed the authority no longer has to be notified of the same activity several times. This affects projects delayed by financing or labour, which is not rare, and it saves a procedure whose only content would have been to report that the work is continuing.
3. When a design is also required
A notice and a design are not the same thing, and which applies depends on the type and size of the building and on the work being done, under Annex 1 to the Building Code. The table must be read afresh for every project.
In some cases a building notice alone suffices; in others a building design must be added to it. Where a design is required, it carries its own requirements, including signature by its author and by the competent person.
The requirement of a design does not turn the procedure into a permit procedure, but it changes the volume of preparation and therefore the time: ten days of procedure do not help if preparing the design takes a month. A design cost is added to the budget.
4. What lengthens the procedure
Three situations show that ten days is not always final. The period can extend on an enquiry from the authority.
| Situation | Effect |
|---|---|
| The authority returns the notice for corrections | the period effectively starts again |
| A competent authority has to check additional conditions | the procedure may follow the permit procedure's deadline |
| The notice is incomplete | the most common reason for rejection |
The second row is the most surprising for a client, because a longer deadline then applies although what was submitted was a notice. This cannot be foreseen from the table alone, which is why in a complex case it is worth contacting the local authority in advance rather than treating ten days as a guarantee.
5. The cost
A building notice carries no state fee: where no building permit is required, no state fee is payable either. The cost then comes from the design rather than the fee.
A cost nonetheless arises from the design where one is required, and with a notice that can be a larger item than the procedure itself. A free procedure therefore does not mean free preparation.
Summary and four practical rules
A building notice is notification, and with it silence is consent: it is submitted at least 10 days before construction begins, and if the authority says nothing within 10 days work may start. Validity rose on 1 August 2026 from two years to four, which reduces repeat notification for projects that run late. The notice carries no state fee, but the design, where required, does.
Four rules: count ten days before the planned start rather than after it. Check whether a design is required, since it determines the preparation time. Do not treat silence as certainty in a complex case, but contact the local authority in advance. Allow for the new four-year validity.
This article offers professional orientation as at the date of verification. It does not replace the assessment of the local authority.