Retaining walls

Retaining walls

You build a retaining wall to hold back a bank of earth; even low walls are exposed to large forces from water, the earth, and surrounding structures. Careful consideration must be given to these forces to prevent wall failure.

There are different types of retaining walls and not all require consent.

Read this BRANZ Build article by Alide Elkink on Retaining Walls

Retaining walls (Elkink, 2010)

Exempt work

Not all retaining walls require building consent.

However, never assume you do not need consent all check! If you do not have the required consent you may be issued with an infringement notice. This could even lead to prosecution of the homeowner (and heavy fines!).

Under the Building Act 2004, all building work must have consent unless it is covered by sections 41 and 42A of the Act.

Section 41 - Exemption 20 - retaining walls 

Covers low risk building work; though it must still comply with the Building Code.

A retaining wall does not require consent if it is retaining less than 1.5 m of ground and does not support a surcharge (extra load on the land due to a carpark, driveway, slope, building, etc. See Schedule 1 guidance for more detail. 

See Building Performance - Part 1: Exempted building work that can be carried out by anyone 20. Retaining walls