If you're planning a retaining wall in New Zealand, you may have heard the term producer statement thrown around by your builder or council. In short, it's a formal document prepared by a suitably qualified person — usually a geotechnical or structural engineer — confirming that the design and/or construction of your retaining wall complies with the NZ Building Code. Knowing when you need one can save you time, money, and headaches down the track.
What Exactly Is a Producer Statement?
A producer statement (often abbreviated to PS) is a written declaration from a qualified professional stating that, to the best of their knowledge, the work they've designed or inspected meets the requirements of the New Zealand Building Code. There are four common types:
- PS1 – Design: The engineer confirms the design complies with the Building Code.
- PS2 – Design Review: A second engineer reviews and confirms another's design.
- PS3 – Construction Observation: The engineer confirms construction was carried out in accordance with the consented design.
- PS4 – Construction Review: A review of completed construction against the design.
For retaining walls, you'll most commonly encounter PS1 (design) and PS3 (construction observation). Your local council's building consent authority (BCA) uses these documents as supporting evidence when processing your consent application and issuing a code compliance certificate (CCC).
When Does a Retaining Wall Need a Building Consent?
Not every retaining wall requires a building consent — but many do. Under Schedule 1 of the Building Act 2004, some retaining walls are exempt from consent, provided they meet specific criteria. As a general guide:
| Wall Height | Surcharge Present? | Consent Likely Required? |
|---|---|---|
| Up to 1.5 m | No | Usually exempt |
| Up to 1.5 m | Yes (e.g. driveway, building nearby) | Often required |
| Over 1.5 m | Any situation | Almost always required |
Important: These are general guidelines only. Exemptions depend on site-specific factors such as soil type, proximity to boundaries, and what's above or below the wall. Always confirm with your local council before starting work — what's exempt in one district may not be in another.
You can read more about Schedule 1 exemptions and consent requirements on the MBIE Building Performance website.
When Is a Producer Statement Required for a Retaining Wall?
Once a building consent is required, your council will almost certainly ask for engineering documentation — and that typically means a producer statement. You'll generally need one when:
- The wall is over 1.5 metres in retained height
- The wall is subject to surcharge loading (a driveway, vehicle traffic, a building, or a pool sitting above or near the wall)
- The site has poor, unstable, or variable soils (common in many parts of NZ, particularly on hillside sections)
- The wall is close to a property boundary or existing structure
- The wall uses a specific engineered system (such as timber pole walls, concrete block, or reinforced earth systems) that requires design sign-off
- Your council's BCA specifically requests one as part of the consent process
Even for walls that are technically exempt from consent, an engineer's involvement is strongly recommended if the ground conditions are uncertain or the consequences of failure are significant — for example, if a collapse could damage a neighbouring property or a building.
Who Can Provide a Producer Statement?
Producer statements must be prepared by a suitably qualified and competent professional. For retaining walls, this is typically a Chartered Professional Engineer (CPEng) with experience in geotechnical or structural engineering. The engineer takes on professional liability for the statement, so they will usually want to carry out their own site investigation and soil assessment before signing off.
Your retaining wall builder can often recommend engineers they've worked with, or you can search through professional engineering bodies. BRANZ also provides useful technical guidance on retaining wall construction and soil considerations.
The Consent and CCC Process
Here's a simplified overview of how producer statements fit into the building consent process for a retaining wall:
- Engage an engineer to assess the site and prepare a design (PS1).
- Apply for building consent — submit the PS1 along with plans and specifications.
- Council grants consent — construction can begin.
- Engineer carries out construction observation during key stages of the build.
- Engineer issues PS3 confirming construction matches the consented design.
- Apply for a Code Compliance Certificate (CCC) — the PS3 supports this application.
Skipping any of these steps can result in your council refusing to issue a CCC, which can cause serious problems if you ever sell the property.
When to Call a Professional
Retaining walls that require a producer statement are, by definition, complex enough to warrant professional engineering input. If your wall is over 1.5 metres, on a challenging site, or near a boundary or structure, engage a licensed building practitioner and a qualified engineer from the outset. Attempting to build without proper documentation can result in costly remediation, enforcement action, or liability if the wall fails.
You can find qualified retaining wall builders in your area right here on tradedirectory.co.nz. Look for builders who have experience working alongside engineers and who understand the consent process in your region.
For work involving Licensed Building Practitioners (LBPs), check the register at lbp.govt.nz to verify credentials.
Licensed Building Practitioner (LBP)
