When hiring a concreter in New Zealand, you should generally expect a workmanship warranty of somewhere between one and five years, though this varies by contractor and job type. There is no single mandated warranty period for concrete work under NZ law, so it pays to know what to ask for, what's reasonable, and what your broader consumer rights are.
What Is a Workmanship Warranty?
A workmanship warranty (sometimes called a labour guarantee) means the concreter stands behind the quality of their work. If defects arise from poor installation — such as excessive cracking, surface delamination, or uneven falls — the contractor agrees to return and remedy the problem at no extra cost to you.
It is important to distinguish this from a materials warranty, which is provided by the product manufacturer (e.g., the concrete supplier or admixture brand) and covers defects in the materials themselves, not how they were placed.
Typical Warranty Periods in NZ
As a general guide, here is what you might expect from different types of concrete work:
| Type of Work | Typical Workmanship Warranty |
|---|---|
| Residential driveway or path | 1–3 years |
| Concrete slab (house floor) | 2–5 years |
| Decorative/exposed aggregate | 1–3 years |
| Structural concrete work | 5+ years (often tied to consent) |
These are approximate ranges only — always confirm the specific warranty in writing with your contractor before work begins.
Your Rights Under NZ Consumer Law
Even if a concreter offers no formal written warranty, you still have protections under the Consumer Guarantees Act 1993 (CGA). Under the CGA, services must be carried out with reasonable care and skill, and the result must be fit for purpose. If the work falls short, you are entitled to have it remedied.
The Contract and Commercial Law Act 2017 may also be relevant if there is a written contract in place. Consumer NZ has helpful plain-English guidance on your rights when tradespeople don't deliver.
For work that requires a building consent — such as a concrete slab for a new dwelling or major addition — the MBIE Building Performance framework also provides a degree of protection, as the work must meet the NZ Building Code and will be inspected by your local council.
What Should Be Covered in a Warranty?
A good workmanship warranty should clearly state:
- What is covered — e.g., cracking beyond acceptable limits, surface defects, drainage failures
- What is excluded — e.g., damage from tree roots, vehicle overloading, ground movement, or normal shrinkage cracking
- The warranty period — start date and end date
- How to make a claim — who to contact and within what timeframe
- Remedy offered — repair, replacement, or refund
Always get the warranty in writing as part of your contract. A verbal promise is very difficult to enforce.
Normal Cracking vs Defective Work
One common point of dispute is cracking. Plastic shrinkage cracking (hairline cracks that appear as concrete cures) is considered normal and is generally not a warranty issue. However, structural cracking, wide cracks (typically over 0.3 mm), or cracking that allows water ingress may indicate a workmanship problem.
Control joints (saw cuts or formed joints) should be placed at regular intervals to manage shrinkage — if your concreter skipped these, that could be a legitimate warranty claim. BRANZ publishes technical guidance on acceptable concrete finishes and defect thresholds that can help you assess a dispute.
What to Ask Before Hiring a Concreter
- Do you provide a written workmanship warranty, and for how long?
- Are you a Licensed Building Practitioner (LBP) if the work requires consent?
- Can you provide references from recent similar jobs?
- What concrete mix design and strength (MPa) will you use?
- How will you manage curing to reduce cracking?
For consented work, check whether your concreter holds the relevant LBP licence class, as certain structural concrete work is restricted building work that must be carried out or supervised by an LBP.
When to Call a Professional
Always use a qualified, experienced concreter for:
- House slabs and structural pads — these must meet NZS 3604 or specific engineering specifications and will require building consent in most cases
- Retaining walls over 1.5 m — likely require consent and engineering input
- Any work near drainage or services — to avoid damaging underground infrastructure
If you have a warranty dispute that cannot be resolved directly with your contractor, you can seek assistance through the Disputes Tribunal (for claims up to $30,000) or seek legal advice. Consumer NZ's guidance is a good starting point.
Finding a reputable local concreter is the best way to avoid warranty headaches in the first place. You can search for qualified concreters in your area on tradedirectory.co.nz.
Site Safe
