What is the Piano Casa and does it apply to your house?
The Piano Casa laws are regional laws that allow existing buildings to be extended beyond the municipal plan, often by around 20%, on conditions that vary by region. Any extension options depend on the regional and local rules in force and on the lawful existing state.
Some examples
| Region | Rule |
|---|---|
| Campania | up to 20% for single and two-family houses, only on built volume |
| Lazio | up to 20% of volume or floor area; limits vary |
| Puglia | up to 20%, with a cap around 300 m³ |
| Marche | up to 20% after a municipal council decision |
| Toscana | L.R. 24/2009 expired on 31-12-2022, not renewed |
| Veneto | L.R. 14/2019: base 15%, up to 40% |
| Liguria | L.R. 49/2009, permanent, percentages by volume band |
Examples from trade sources, to be checked against the regional law in force before use.
What you can do with a property also depends on other rules, such as the zoning certificate (CDU) and landscape and heritage constraints. For one address, the free Dossier Immobile preview brings them together.
The limits
- Which volume counts, which reference date applies and which exceptions exist is set by the regional law; the Council of State (2040/2026) decided one such case.
- For buildings regularised by amnesty the Constitutional Court reopened the issue in 2026 (judgment 86/2026): ask the Comune.
The 2026 Piano Casa is something else
The 2026 national Piano Casa (L. 116/2026) concerns strategic housing programmes with a commissioner, not a right to extend an individual house.
What Dossier Immobile does
This dossier does not calculate any right to extend: if you are interested in an extension, check the regional law with a qualified technician.
Can I buy counting on an extension?
Only after checking the regional law, the stato legittimo and the municipal plan with a technician.
Sources
- Marche Region: Piano Casa effects extended
- Mansarda.it: Piano Casa, extensions and news
- LavoriPubblici: Council of State 2040/2026
- Constitutional Court 86/2026 (commentary)
- LavoriPubblici: L. 116/2026
Dossier Immobile is a private service by SRI Group BV (VAT BE1037052239), not connected to any public authority: it brings together public data, with the source and date of every item.
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