Urban planningUseful information
A Déclaration de conformité des travaux or a certificate of authorization is required to build a retaining wall on your property. The standards for a retaining wall are as follows:
• A retaining wall may be more than 1.5 m high if it is terraced and if each terrace is spaced so that the natural slope of the lot remains unchanged. The width of each terrace must be greater than the average height of the walls on either side. The height of each wall between terraces must not exceed 1.5 m.
• Each terrace must be grassy or landscaped.
• If a fence is built less than 1 m from the top of the retaining wall, the combined height of the fence and topmost wall must not exceed 3 m.
• A retaining wall higher than 1.25 m must be protected by a fence or hedge at least 1.2 m high.
• Low walls and retaining walls may be built of the following materials:
– natural stone
– landscape blocks (self-supporting blocks)
– continuously poured concrete