Retaining Wall Costs in NZ
Retaining wall pricing depends heavily on height, length, material, and access. Steep sites with poor access can double the labour cost.
Consent Requirements
Under the NZ Building Act, retaining walls generally require building consent if: - Height exceeds 1.5 metres above the lowest ground level - The wall is within 1.5m of a boundary or building
Always check with your local council — some have stricter rules.
Cost Guide by Type
| Type | Installed cost (per m²) |
|---|---|
| Keystone / concrete block | $350–$550/m² |
| H5 timber sleepers | $280–$420/m² |
| Poured concrete | $500–$800/m² |
| Gabion baskets | $300–$500/m² |
Drainage is Critical
All retaining walls need drainage to prevent hydrostatic pressure buildup — the #1 cause of retaining wall failure. Always include: - 300–400mm drainage aggregate backfill - Geotextile filter fabric - Ag-pipe at the base with outlets every 3–4m
Use our Earthworks Calculator to estimate excavation volumes.