If a waterproofing job in your home has failed — whether it's a leaking deck, a wet basement, or a poorly sealed bathroom — you have real options for getting the problem resolved. New Zealand has several consumer protection pathways available to homeowners, and knowing which one to use can save you time, money, and stress.
Start With the Waterproofer Directly
Before escalating, give the waterproofer a chance to fix the problem. This is often the fastest route to a resolution. Contact them in writing (email is ideal so you have a record) and clearly describe:
- What the defect or failure is
- When you first noticed it
- What outcome you're seeking (repair, refund, or compensation)
Keep all correspondence, photos of the damage, and copies of your original contract or quote. A reasonable tradesperson will want to return and assess the work — especially if it's still within any workmanship warranty period they offered.
Check Your Consumer Rights Under the Consumer Guarantees Act
If the waterproofer was working on your home (not a commercial property), the Consumer Guarantees Act 1993 (CGA) applies. Under the CGA, services must be carried out with reasonable care and skill, and the result must be fit for purpose. If the waterproofing has failed and it's due to poor workmanship, you are entitled to have it remedied at no extra cost.
The Fair Trading Act 1986 also protects you if you were misled about the scope of work, materials used, or the tradesperson's qualifications.
For guidance on your rights, Consumer NZ is an excellent starting point.
Was the Waterproofer a Licensed Building Practitioner?
In New Zealand, certain waterproofing work is restricted building work (RBW) — meaning it must be carried out or supervised by a Licensed Building Practitioner (LBP). This typically applies to waterproofing that forms part of the building envelope, such as wet area membranes in bathrooms, decks over habitable spaces, and external cladding systems.
If your waterproofer carried out restricted building work without an LBP licence, or if a licensed practitioner did the work poorly, you can make a formal complaint to the Licensed Building Practitioners scheme. The LBP Board can investigate complaints about conduct, competence, and whether the work met the requirements of the NZ Building Code (particularly clauses E2 External Moisture and E3 Internal Moisture).
To check whether your waterproofer holds a current LBP licence, use the public register on the LBP website.
Escalate to the Disputes Tribunal
If direct negotiation fails and the amount in dispute is under $30,000 (or up to $100,000 by agreement), the Disputes Tribunal is a low-cost, straightforward option. You don't need a lawyer, and hearings are held locally. The Referee can order the tradesperson to repair the work, refund money, or pay compensation.
You can file a claim through the Ministry of Justice website. Keep all your evidence organised — photos, written communications, quotes for remedial work from other tradespeople, and any building inspection reports.
Consider a Building Inspector's Report
Before going to the Disputes Tribunal or making a formal complaint, it's worth getting an independent building inspection report. A qualified inspector can document the failure, identify the likely cause, and confirm whether the work meets the NZ Building Code. This report can be powerful evidence in any dispute.
BRANZ (the Building Research Association of New Zealand) publishes technical guidance on waterproofing standards and best practice, which can also help you understand what the work should have looked like.
If a Building Consent Was Involved
Some waterproofing work requires a building consent — for example, a new deck over a habitable space or significant alterations to a wet area. If consented work has failed, you may also have a pathway through your local council's building department. Councils can investigate whether work was completed in accordance with the consent and the Building Code.
For general guidance on building consents and your rights, visit MBIE Building Performance.
Document Everything — From Day One
Whatever path you take, thorough documentation is your best asset:
- Photographs of the defect and any resulting damage (dated)
- Written records of all conversations with the tradesperson
- Copies of the original contract, invoice, and any warranties
- Quotes from other waterproofers for remedial work
- Inspection reports from independent professionals
When to Call a Professional
If the waterproofing failure has caused significant water damage to your home's structure, don't wait — get a qualified tradesperson in to assess and stop any ongoing damage as soon as possible. Mould and structural timber damage can escalate quickly, particularly in New Zealand's wetter regions. You can find qualified, local waterproofing professionals on tradedirectory.co.nz.
If you're unsure whether the original work required an LBP or a building consent, contact your local council's building department for advice before proceeding with any remedial work.
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SiteWise
Licensed Building Practitioner (LBP)
