A defects liability period (DLP) is a set window of time after a building project reaches practical completion during which your builder is contractually obliged to return and fix any defects that emerge from their work. Think of it as a warranty period built into your building contract — it protects you from having to pay twice for work that wasn't done properly the first time.
What Does "Practical Completion" Mean?
Practical completion is the point at which the building work is substantially finished and the property is fit for its intended use, even if a few minor items are still outstanding. It is usually confirmed in writing between you and your builder. From this date, the defects liability period clock starts ticking. Make sure you get this date documented clearly in your contract.
How Long Is a Defects Liability Period in New Zealand?
There is no single fixed length set by law — the duration is agreed in your building contract. However, common industry practice in New Zealand is:
| Contract Type | Typical DLP Length |
|---|---|
| Residential new build (standard) | 3 to 12 months |
| NZS 3910 (commercial/civil) | 12 months |
| Master Build Guarantee projects | Up to 10-year structural guarantee |
| New Build (Consumer Guarantees Act) | Reasonable quality, no fixed end |
For most residential projects, 12 months is a widely accepted benchmark. Always check what your specific contract states before signing.
What Does It Cover?
During the DLP, the builder is responsible for fixing defects that:
- Result from poor workmanship or non-compliant materials
- Were not visible or apparent at practical completion
- Arise from the builder's failure to meet the NZ Building Code
It generally does not cover:
- Fair wear and tear
- Damage caused by you or third parties after handover
- Issues resulting from your own maintenance failures
- Defects you knew about and accepted at practical completion
Your Rights Under New Zealand Law
Even outside a formal DLP, you have important legal protections. The Consumer Guarantees Act 1993 requires that building work is carried out with reasonable care and skill, and that materials are fit for purpose. If a builder's work fails to meet these standards, you may have remedies regardless of whether a DLP is written into the contract.
Additionally, MBIE Building Performance provides guidance on your rights when building work does not comply with the Building Code. Structural and weathertightness defects can carry longer implied obligations under the Building Act 2004, so it's worth understanding these protections.
BRANZ is also a useful resource for understanding building performance standards and what constitutes acceptable construction quality in New Zealand conditions.
How to Manage Your Defects Liability Period
Keep good records
Document everything at practical completion. Walk through the property with your builder and create a defects list (or "snag list") of any items already identified. Photograph everything and keep copies of all correspondence.
Report defects promptly
As soon as you notice a defect, notify your builder in writing — email is fine. Describe the issue clearly and include photos. Delaying notification can complicate your claim.
Give the builder a reasonable opportunity to fix it
Under most contracts, the builder has the right to return and remedy defects before you can engage someone else at their cost. Check your contract for the timeframe allowed.
Use a written contract
Always have a written building contract. The Licensed Building Practitioners scheme requires LBPs to carry out or supervise restricted building work (RBW), which includes structural and weathertightness work on homes. Using a licensed practitioner gives you an additional layer of accountability.
What If the Builder Refuses to Return?
If your builder won't respond or fix the defects within the DLP, you have several options:
- Negotiate — put your concerns in writing and request a formal response
- Mediation or adjudication — many building contracts include a dispute resolution process
- Disputes Tribunal — for claims up to $30,000 (or $60,000 by agreement)
- District Court — for larger claims
- Consumer NZ — Consumer NZ has practical guidance on resolving disputes with tradespeople
If the builder holds a Master Build or Certified Builders guarantee, contact the relevant guarantee provider directly.
When to Call a Professional
If you suspect defects relate to structural integrity, weathertightness, plumbing, or electrical work, get an independent assessment from a qualified professional before attempting any DIY fixes — doing so without proper advice could affect your legal position. A Licensed Building Practitioner or registered engineer can provide a written assessment that strengthens your case if the dispute escalates.
You can find qualified, reputable local builders and inspectors on tradedirectory.co.nz to help you assess defects or manage remedial work.
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