Which building consent your project requires

Article 3 of Presidential Decree 380 of 2001 defines the categories of building work, from routine maintenance through to urban restructuring. The code attaches a consent regime to each category, and the correct sequence of reasoning therefore has two steps: first classify the works, then identify the consent.

Reversing the two steps is the origin of most challenges. Works filed under an insufficient consent do not become lawful because the sportello, the one stop building office, accepted the filing: the classification remains open to challenge, and the consequences for the regularity of the property surface years later, typically on a sale.

The table is an orientation map, not a decision rule. The exact scope of each regime is set by the provisions establishing it, and is covered in the dedicated pages.

Article 6 of the code lists the works that may be carried out without any consent. Decree Law 69 of 2024, converted by Law 105 of 2024 and known as the Salva Casa decree, widened that scope, extending among other things retractable and fully transparent panoramic glazing to the enclosure of porticoes and adding sun and weather protection structures of the awning type.

Supporting article 6 is the glossary approved by ministerial decree of 2 March 2018, listing the principal works that may be carried out as permit free activity. Two cautions apply to that document. The first is that the list is expressly non exhaustive, and the absence of an item does not imply that a consent is required. The second is that inclusion in the glossary is not sufficient: the work remains permit free only if it meets the substantive requirements.

The point most often misread is that free does not mean unconstrained. Permit free works remain subject to municipal planning instruments and to sector legislation, in particular seismic, safety, fire, health and hygiene, energy efficiency, hydrogeological risk and the code of cultural heritage and landscape.

A second level of checking concerns constraints, and it operates independently of the building consent. The consent regime does not absorb the constraints regime.

Permit free work on a property in a landscape protected area may require landscape authorisation. Work on a heritage asset requires authorisation from the soprintendenza, the heritage authority. Work affecting structural elements triggers the seismic requirements set by regional legislation.

These authorisations neither replace the building consent nor are replaced by it: they add to it. The correct checking sequence therefore comprises three distinct questions, on the category of works, on the constraints affecting the property and on the sector regimes triggered by the operations envisaged.

The code is national, but its application runs through local instruments. The regolamento edilizio comunale, the municipal building regulation, and the technical implementation rules of the local plan may refine definitions, impose further requirements and govern matters the national rule leaves to the local level.

The operational consequence is that identifying the consent should always be checked against the municipal rules before filing. On some categories of work the practice of the local offices varies appreciably from one municipality to another, and a preliminary check costs less than a request for further information once the review is under way.

It should be added that some regions have exercised their legislative competence by receiving the Salva Casa changes autonomously, with outcomes that are not uniform nationally. Checking the regional framework therefore precedes any classification.

The classification exercise comes down to five questions, and it is worth always working through them in the same order. It is worth working through them always in the same order.

Which category of article 3 does the work fall into. This is the question that determines the regime, and the answer depends on the effect of the work on the building, not on its financial size.

Does the work affect structural elements. The answer separates different regimes within the same category and triggers the seismic requirements.

Does the work alter volumes, floor areas, the building envelope or elevations. These are the parameters that move a project towards the more onerous regimes.

Does the work involve a change of use. If so, it must be checked whether the change is material as between functional categories, with effects on both the consent and the development contribution.

Is the property subject to constraints. The answer does not change the building consent but adds further authorisations with their own procedures and timescales.

The consequences of a classification error vary with the direction of the error. The two directions are not equally serious.

An excessive consent, meaning a permesso di costruire for work that would have required a SCIA, means longer timescales and higher contributions than necessary but produces no irregularity. It costs time and contribution but does not compromise lawfulness.

An insufficient consent produces a breach, with a sanctions regime depending on the nature and extent of the non conformity and the need to open a regularisation procedure. Professionally, the liability of the certifying professional is also engaged.

A missing consent on work that required one places the property in a state of non conformity that surfaces when its stato legittimo, its lawful planning status, has to be evidenced. That state persists until regularisation.

The pages that follow cover each regime in its exact scope, with the works included and the documentation required. They also carry the boundaries between neighbouring regimes.