The amnesty of buildings has always been one of the most slippery subjects in Italian planning law, fertile ground for creative interpretations and attempts to circumvent legal boundaries.
With proposal no. 13145 of April 10, 2026, the Court of Cassation set a firm mark on a question that had created conflicting orientations between municipal technical offices and value judges: how is the volume calculated for the purposes of the second building amnesty?
The answer is clear, without room for ambiguity. Getting this calculation wrong is no ordinary mistake: it could cost the entire property demolition. A pronunciation that all property owners, technicians and industry professionals should be well aware of.
The premise: a basement that didn’t seem to count
At the heart of the case examined by the Supreme Court was a property whose total volume, adding the upper ground floor and the basement, exceeded the limit of 750 cubic meters defined by art. 39 of Law no. 724/1994 for access to the second amnesty. Once this limit is exceeded, amnesty certificates already issued lose their effectiveness and the demolition order is triggered.
At some point, however, the municipal technical office had recalculated the volumes outside the basement, justifying the choice with the physical characteristics of the room: access through a hatch, minimal natural light, absence of conditions for constant presence of people. The competent judge had supported this approach, also referring to the municipal building regulation. As a result, the building “reduced” in numbers entered the limits and the demolition order was revoked.
A solution that seemed reasonable, almost common sense and that in many similar cases had been accepted by the courts. The Supreme Court, however, overturned everything, clarifying that no physical feature of a room can exempt it from the volumetric calculation, thus paving the way for very serious consequences for anyone in the same situation.
What the Supreme Court finds: volume counts in its entirety, no exceptions
The Court established a principle of absolute clarity: the volume of a property must be calculated as a whole, including all levels, including basements, regardless of their intended use, habitability or structural characteristics. The art. 39 of Law no. 724/1994 does not provide for any category of “non-calculable volume” and it is not possible to introduce it through interpretation.
Municipal building codes, as secondary sources, cannot deviate from the limits set by state law: to accept volumetric exemptions based on local regulations would be to covertly expand the amnesty’s scope, which the legislature never authorized. The rationale is accurate: the amnesty is an extraordinary and reductive measure in terms of the principle of urban legality and must therefore be interpreted strictly and restrictively.
Anyone who owns a property with an amnesty that has already received it would do well to check with a qualified technician that the initial volumetric calculation was done correctly, including each level of the building. Those who today find themselves assessing the forgiveness of a property must therefore take into account the real, total volume, without deluding themselves that they can lighten the calculation by isolating cellars, basements or technical rooms.
