Retaining walls

A retaining wall is a structure holding back soil where there is a change in ground level, common on New Zealand's sloping sites.

Why they matter more than they look

• Consent — retaining walls above a certain height, or retaining a surcharge such as a driveway, generally require building consent. Many existing walls were built without it.
• Cost — replacing a failed retaining wall is expensive, frequently five figures, occasionally six
• Responsibility — where a wall sits on or near a boundary, who is responsible for it is often unclear and is a common source of neighbour disputes

Establishing responsibility

Generally determined by where the wall sits, who benefits, and what is registered. Sometimes there is a registered easement or covenant specifying responsibility; often there is nothing, and it becomes a matter of common law and negotiation.

The Fencing Act does not apply to retaining walls in the way many people assume.

What to check

• Is there a retaining wall on or near a boundary?
• Was it consented, and is there a Code Compliance Certificate?
• What condition is it in — leaning, cracking, bulging, blocked drainage?
• Is there anything on the title dealing with responsibility?

Common misunderstanding

A builder's report may note a retaining wall without assessing it structurally. Where a wall is significant or showing signs of movement, get an engineer.

Unconsented retaining walls are extremely common and become the current owner's problem.

Related terms

Last reviewed: 1 August 2026 · General information only, not legal advice.

← Back to the Glossary