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France · Building a shelter

Can I build a private shelter in France?

No French law requires, licenses or funds private shelters. Ordinary planning rules apply: a buried shelter counts by floor area, with a declaration above 5 m².

Updated 2026-10-21· 14 official sources

Short answer. France has no shelter-specific law, permit, declaration or obligation: the government relies on sheltering in existing buildings 1314, and a private shelter follows ordinary planning law 5. A fully buried structure creates no footprint but does create floor area 129. For a new construction: no formality up to 5 m², a prior declaration above 5 m² and up to 20 m², a building permit above 20 m² 675. The mairie handles the application 12.

Information verified on 21 October 2026.

Is there a French law on private shelters?

No. No French text requires a shelter in homes or new buildings. In 1993 a member of parliament asked the Prime Minister to encourage, or even require ("inciter, voire obliger"), developers to build shelters. The answer was that sheltering is planned in existing premises and that this approach is not a policy of building shelters 13. In 2023, the Prime Minister said that France's nuclear deterrence sets it apart from European partners that "ont fondé une partie de leur défense sur la construction d'abris antiatomiques" (based part of their defence on building nuclear shelters) 14.

A resolution proposal registered at the National Assembly on 27 July 2026 (no. 3103) asks the government to study extending a protected-space requirement to new private buildings above a surface threshold. It also asks for a national technical reference for communal shelters, funding for communes and an inventory of possible shelters. A resolution is not a law, and this one had not been adopted as of 21 October 2026 4.

No official source read mentions a public subsidy for private shelters, and no official French technical standard for shelters was found. The resolution's funding and technical proposals concern communal shelters 4.

Which planning rules apply to a shelter?

Ordinary planning law under the Code de l'urbanisme. Article R*421-1 says a new construction needs a building permit unless it is exempt from any formality or needs only a prior declaration 5. Outside a site patrimonial remarquable, the surroundings of historic monuments and classified sites, the thresholds are:

Project Rule
New construction: footprint and floor area each up to 5 m², height up to 12 m No formality (R*421-2) 6
New construction: footprint or floor area above 5 m², each up to 20 m², height up to 12 m Prior declaration (R421-9) 7
New construction above those limits Building permit (R*421-1) 5
Works on an existing building creating more than 5 m² and up to 20 m² of footprint or floor area Prior declaration (R*421-17) 11
Same works in an urban zone of a local plan (PLU) Prior declaration up to 40 m², with exceptions 11
Works on an existing building creating more than 20 m² (40 m² in a PLU urban zone) Building permit (R*421-14) 10

The rules for works on an existing building (articles R421-14 and R421-17) apply to "travaux exécutés sur des constructions existantes" (works carried out on existing constructions); a separate structure follows the rules for new constructions 10115. Your mairie confirms which category your project falls into. The application goes to the mairie 12. If the floor area of the construction exceeds 150 m², the plans must be drawn up by an architect 1.

Does a buried shelter count toward the thresholds?

Yes, through its floor area. In a written answer published on 20 September 2012, the housing ministry stated: "une construction enterrée ne constitue pas d'emprise au sol. En effet, seuls les éléments aériens éventuels d'une telle construction, sont constitutifs d'emprise au sol" (a buried construction creates no footprint; only its above-ground parts do) 12. The same answer says a buried cellar on bare land creates floor area and therefore needs an authorisation 12.

This matches the code's definitions. Footprint is "la projection verticale du volume de la construction" (the vertical projection of the construction's volume) 8. Floor area is the sum of the floor areas of each closed and covered level, measured inside the walls 9. The deductions include floors with a ceiling height of 1.80 m or less, and cellars annexed to dwellings only when they are served solely by a common part, which a private house shelter usually is not 912. The 2012 answer cites former article R. 112-2, replaced by R111-22 with the same cellar rule 129.

Your mairie confirms which procedure applies to your plot and project. Phaenyx does not say whether a given project needs a permit or a declaration.

Who should I talk to before any work?

  1. Your mairie, for the planning procedure that applies to your plot and your project 12.
  2. A qualified structural engineer, for anything underground or load-bearing. Phaenyx gives no construction instructions. Background reading: Can you bury a shipping container as a shelter? and What does it take to make a shipping container safe underground?.
  3. An architect, required if the floor area exceeds 150 m² 1.

For the technical concepts, see What is a shelter's protection factor?, How much fresh air does a shelter need? and How does NBC air filtration work in a shelter?.

Do I need a private shelter in France?

Official guidance does not ask households to build one. It covers sheltering in place in an ordinary building, with doors and windows closed and ventilation off, until the authorities give instructions 3. See France public shelters and Shelter in place or evacuate?.

Frequently asked questions

Is it legal to build a bunker in France?

Yes, under ordinary planning rules: no law specifically covers private shelters 1314. A new construction needs a prior declaration above 5 m² of floor area and a building permit above 20 m² 75. Ask your mairie 12.

Does an underground shelter need a permit in France?

It depends on its floor area. A buried structure creates no footprint but does create floor area, so the floor-area thresholds apply: prior declaration above 5 m², building permit above 20 m² for a new construction 1275.

Am I required to have a shelter in a new house?

No. No French text requires one. The government's stated approach is to shelter people in existing buildings rather than build shelters 1314. A 2026 resolution proposal asks for a study of such a requirement, but it is not law 4.

Does the French government subsidise private shelters?

No official source read mentions a subsidy for private shelters. Funding proposals in the 2026 resolution proposal concern communal shelters 4.

Sources

  1. Service-Public.gouv.fr (DILA, Premier ministre) — Permis de construire (PC) — https://www.service-public.gouv.fr/particuliers/vosdroits/F1986 (accessed 2026-10-21)
  2. Service-Public.gouv.fr (DILA, Premier ministre) — Déclaration préalable (DP) — https://www.service-public.gouv.fr/particuliers/vosdroits/F17578 (accessed 2026-10-21)
  3. Secrétariat général de la défense et de la sécurité nationale (SGDSN) — Tous responsables. Face aux risques, agissons : bien préparés, bien protégés, tous engagés — https://www.ecologie.gouv.fr/sites/default/files/documents/SGDSN_Guide_Tous%20responsables.pdf (accessed 2026-10-20)
  4. Assemblée nationale — Proposition de résolution n° 3103 visant à garantir un abri accessible dans chaque commune pour renforcer la protection de la population française — https://www.assemblee-nationale.fr/dyn/17/textes/l17b3103_proposition-resolution.pdf (accessed 2026-10-21)
  5. Légifrance (DILA) — Code de l'urbanisme, article R*421-1 — https://www.legifrance.gouv.fr/codes/article_lc/LEGIARTI000051190132 (accessed 2026-10-21)
  6. Légifrance (DILA) — Code de l'urbanisme, article R*421-2 — https://www.legifrance.gouv.fr/codes/article_lc/LEGIARTI000050497056 (accessed 2026-10-21)
  7. Légifrance (DILA) — Code de l'urbanisme, article R421-9 — https://www.legifrance.gouv.fr/codes/article_lc/LEGIARTI000050497051 (accessed 2026-10-21)
  8. Légifrance (DILA) — Code de l'urbanisme, article R*420-1 — https://www.legifrance.gouv.fr/codes/article_lc/LEGIARTI000028678466 (accessed 2026-10-21)
  9. Légifrance (DILA) — Code de l'urbanisme, article R111-22 — https://www.legifrance.gouv.fr/codes/article_lc/LEGIARTI000031721274 (accessed 2026-10-21)
  10. Légifrance (DILA) — Code de l'urbanisme, article R*421-14 — https://www.legifrance.gouv.fr/codes/article_lc/LEGIARTI000031764577 (accessed 2026-10-21)
  11. Légifrance (DILA) — Code de l'urbanisme, article R*421-17 (version en vigueur depuis le 22 février 2026) — https://www.legifrance.gouv.fr/codes/article_lc/LEGIARTI000053561259 (accessed 2026-10-21)
  12. Sénat — Construction enterrée et autorisation d'urbanisme (question écrite n° 00941, réponse du Ministère de l'égalité des territoires et du logement publiée le 20/09/2012) — https://www.senat.fr/questions/base/2012/qSEQ120700941.html (accessed 2026-10-21)
  13. Assemblée nationale — Défense civile (question écrite n° 4110, réponse du Premier ministre publiée le 6 septembre 1993) — https://www.assemblee-nationale.fr/dyn/10/questions/QANR5L10QE4110 (accessed 2026-10-21)
  14. Sénat — Capacités d'abris souterrains destinés à protéger la population en cas de conflit armé nucléaire (question écrite n° 05279, réponse du 25/05/2023) — https://www.senat.fr/questions/base/2023/qSEQ230205279.html (accessed 2026-10-21)

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Sources

  1. Service-Public.gouv.fr (DILA, Premier ministre) · Permis de construire (PC) checked 2026-10-21
  2. Service-Public.gouv.fr (DILA, Premier ministre) · Déclaration préalable (DP) checked 2026-10-21
  3. Secrétariat général de la défense et de la sécurité nationale (SGDSN) · Tous responsables. Face aux risques, agissons : bien préparés, bien protégés, tous engagés checked 2026-10-20
  4. Assemblée nationale · Proposition de résolution n° 3103 visant à garantir un abri accessible dans chaque commune pour renforcer la protection de la population française checked 2026-10-21
  5. Légifrance (DILA) · Code de l'urbanisme, article R*421-1 checked 2026-10-21
  6. Légifrance (DILA) · Code de l'urbanisme, article R*421-2 checked 2026-10-21
  7. Légifrance (DILA) · Code de l'urbanisme, article R421-9 checked 2026-10-21
  8. Légifrance (DILA) · Code de l'urbanisme, article R*420-1 checked 2026-10-21
  9. Légifrance (DILA) · Code de l'urbanisme, article R111-22 checked 2026-10-21
  10. Légifrance (DILA) · Code de l'urbanisme, article R*421-14 checked 2026-10-21
  11. Légifrance (DILA) · Code de l'urbanisme, article R*421-17 (version en vigueur depuis le 22 février 2026) checked 2026-10-21
  12. Sénat · Construction enterrée et autorisation d'urbanisme (question écrite n° 00941, réponse du Ministère de l'égalité des territoires et du logement publiée le 20/09/2012) checked 2026-10-21
  13. Assemblée nationale · Défense civile (question écrite n° 4110, réponse du Premier ministre publiée le 6 septembre 1993) checked 2026-10-21
  14. Sénat · Capacités d'abris souterrains destinés à protéger la population en cas de conflit armé nucléaire (question écrite n° 05279, réponse du 25/05/2023) checked 2026-10-21

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