Is a permit required in Moncton to build a new concrete retaining wall over one metre in height on a residential property?

Yes, a building permit is required in Moncton for any retaining wall over one metre (3.3 feet) in height. The City of Moncton follows standard New Brunswick building practices that require permits for retaining walls exceeding this threshold due to the structural loads and safety considerations involved.

For retaining walls over 1.2 metres (4 feet) in height, you'll also need engineered drawings prepared by a professional engineer licensed in New Brunswick. The engineer must calculate soil pressure, drainage requirements, foundation depth, and reinforcement specifications to ensure the wall can safely resist the forces acting against it — particularly important in New Brunswick's freeze-thaw climate where frost heave adds significant pressure behind retaining structures.

The permit process in Moncton typically involves:

• Submitting a building permit application with site plans showing the wall location, height, and proximity to property lines


• Providing construction drawings (engineered drawings for walls over 4 feet)


• Paying permit fees (usually $100-300 depending on wall size and complexity)


• Scheduling inspections for footing excavation, reinforcement placement, and final construction

New Brunswick's frost depth requirements are critical for retaining wall footings. In the Moncton area, footings must extend at least 4 feet (1.2 metres) below finished grade to prevent frost heave from shifting or tilting the wall. A retaining wall that moves even slightly loses its structural integrity and becomes a safety hazard.

Drainage behind the wall is equally important in New Brunswick's wet Maritime climate. Proper weeping tile, gravel backfill, and surface drainage prevent hydrostatic pressure buildup that can cause wall failure. Spring snowmelt and heavy Maritime rains create significant water pressure behind inadequately drained retaining walls.

Contact Moncton's Building Inspection Department at City Hall (655 Main Street) or call 506-853-3516 to confirm specific requirements for your project. They can advise on setback requirements from property lines, height restrictions in your zoning area, and whether your specific wall design requires engineering review.

When to Hire a Professional: Any retaining wall over 2 feet should be built by an experienced concrete contractor familiar with NB soil conditions, frost depth requirements, and proper drainage installation. The consequences of retaining wall failure — soil movement, property damage, safety hazards — make this a poor choice for DIY construction.

Need help finding a professional concrete contractor experienced with retaining walls? New Brunswick Concrete can match you with local professionals through the New Brunswick Construction Network.