Retaining walls

If you’re thinking about building a retaining wall with any part higher than 1.5 metres, or with a structure like a building or driveway near the top, you’ll need a building consent, and possibly a resource consent.

Design of proposed wall

As part of the building consent and resource consent process you need to consider any potential effects on neighbouring properties, like erosion.

You’ll also need to think about the intended lifespan of the structure. The lifespan of a structure is assumed to be 50 years, but you can choose to work to a shorter lifespan.

Height of wall and slope/land use above wall

Most building work requires a building consent and possibly a resource consent. In some circumstances though, retaining walls 1.5 metres high or less don’t require building consent – for example if the ground above the retaining wall is flat, and there’s no additional load such as from a driveway or building.

A retaining wall over 1.5 metres in height is considered to be a building under the District Plan and needs to comply with the relevant zone permitted activity standards for:

• height
• height in relation to boundary
• yard setbacks.

There may be other rules triggered by District Plan rules.