Are there restrictions on building garden walls in France?

Reader Question: We want to build a boundary wall between us and our neighbour, approximately 8m long and 2.2m high but planning permission was refused on the grounds of flooding. Is there any way around this?

Where there are no local restrictions in place, the national standards for garden walls are strange, specifying a minimum height of 2.6m for communes with a population of less than 50,000, and a whopping 3.2m for those with more than 50,000 inhabitants.

Walls should be built with the agreement of neighbours, who can later complain if they feel light or views have been lost.

Full planning permission is not needed but a déclaration préalable de travaux (DP) must be made for walls over 2m high. 

Most garden walls are much lower than this indicating communes have local rules. 

Read more: Explainer: Rights and obligations for shared garden walls in France

Local rules can take three forms: those in the plan local d’urbanisme (PLU), those associated with la carte communale, or the catch-all usages locaux.

Unfortunately for you the rules concerning flood zones, written in the PLU, are both strict and heavily enforced.

Read more:  Can our neighbour in France force us to replace a hedge with a fence?

Whilst a wall lower than 2m high might escape the need for a declaration of works the only way to determine this is at the mairie. 

Alternatively a hedge or a fence may prove more acceptable but again it is likely that local restrictions apply – especially if you are in a flood zone.