Why guarantees matter when hiring a plumber
When you hire a plumber in New Zealand, you are not just paying for a tap swap or a hot water cylinder installation — you are paying for peace of mind that the work will be safe, compliant and durable. A proper guarantee tells you what happens if something leaks, fails or was not installed correctly.
In practice, there are three separate layers of protection to understand:
- The plumber’s workmanship guarantee: a promise about the quality of their labour.
- Product warranties: the manufacturer’s or supplier’s promise about the tapware, cylinders, valves or fittings.
- Your legal rights under the Consumer Guarantees Act 1993 (CGA): minimum protections that apply when a plumber supplies services and goods to a consumer in NZ.
A trustworthy plumber should be clear about all three before work starts, ideally in writing.
What a workmanship guarantee should cover
A workmanship guarantee is the plumber standing behind their own work. It should explain what parts of the job they will fix if there is a fault caused by installation, not by wear and tear or misuse.
A useful workmanship guarantee should cover:
- leaks from joints, fittings or pipework installed by the plumber
- incorrect installation of fixtures or appliances
- poor sealing around plumbing penetrations they created
- failures caused by labour defects, such as wrong slope, loose fittings or incorrect connection
- compliance issues where the work was not carried out to the required standard
It should also clearly state:
- the length of the guarantee — for example, 12 months, 24 months or longer for some work
- what is excluded — such as damage caused by other trades, pre-existing defects, blocked drains due to tree roots, or customer misuse
- how to make a claim — who to contact, how quickly they’ll respond, and whether they will inspect the issue first
- whether call-out fees apply if the problem turns out not to be their fault
Good workmanship guarantees are specific
A vague promise like “we guarantee our work” is not very helpful. Ask for something more concrete. For example, a decent guarantee might say the plumber will rectify defects in workmanship at no cost within 12 months of completion, provided the system has been used normally and serviced as required.
Be cautious if a plumber only offers a verbal promise. In New Zealand, written quotes, scopes and guarantee terms are much easier to rely on if there is a dispute later.
Product warranties: what they are and who is responsible
Product warranties are usually provided by the manufacturer, importer or supplier of the item installed. Common examples include:
- hot water cylinders
- tapware
- mixers and shower valves
- pumps
- water filtration systems
- toilets and cistern components
These warranties often cover manufacturing defects, not installation mistakes.
Key things to check with product warranties
| Item | What to check |
|---|---|
| Warranty length | Is it 1 year, 5 years, 10 years or longer? |
| Who provides it | Manufacturer, importer, retailer or supplier? |
| Registration required | Some warranties need online registration or proof of installation. |
| Installation conditions | Was it installed by a licensed plumber or in line with instructions? |
| Maintenance conditions | Does it require regular servicing or water quality checks? |
| Labour cover | Does it cover only the product, or also the labour to remove and replace it? |
A common trap is assuming a long product warranty covers the full cost of fixing a problem. It may only replace the faulty item, while labour, access and reinstatement costs are extra. For example, if a cylinder manufacturer replaces the cylinder itself, you may still face extra costs if the installer needs to remove cabinetry or reconnect fittings.
Ask the plumber to confirm:
- which products are supplied under warranty
- whether they are an authorised installer for any specialist product
- what proof of purchase or installation documentation you should keep
The Consumer Guarantees Act in New Zealand
The Consumer Guarantees Act 1993 gives New Zealand consumers certain rights when they buy services and goods from a business, including plumbing services.
For plumbing work, the CGA generally requires that services are:
- carried out with reasonable care and skill
- fit for the purpose you made known to the plumber
- completed within a reasonable time if no time is agreed
- supplied for a reasonable price if no price is agreed
If the plumber also supplies goods, the goods must be:
- of acceptable quality
- fit for purpose
- match their description
What “reasonable care and skill” means in practice
A plumber should install and repair work in a competent way, following the manufacturer’s instructions, relevant New Zealand standards, and good industry practice. That includes doing the job safely, using suitable materials, and avoiding shortcuts that could cause leaks, water damage or compliance problems.
If the work is faulty because it was done badly, the CGA may require the plumber to fix it. If the problem is serious and they do not sort it out within a reasonable time, you may have further remedies.
Can a plumber exclude CGA rights?
For ordinary household plumbing work, a business generally cannot contract out of the CGA where you are acquiring services or goods of a kind ordinarily acquired for personal, domestic or household use. Be careful with any contract that tries to limit your rights too much. A valid workmanship guarantee should sit alongside your CGA rights, not replace them.
What recourse you have if the work is faulty
If you think plumbing work is faulty, act quickly. Water damage can escalate fast, especially in colder months when pipes, cylinders and under-house areas may be more vulnerable.
Step 1: Document the problem
- Take clear photos or video of the issue.
- Note when you noticed it and what happened.
- Keep the invoice, quote, warranty documents and any texts or emails.
- If there is water damage, show the extent and where it appears to be coming from.
Step 2: Notify the plumber in writing
Contact the plumber as soon as possible and explain the fault clearly. Ask them to inspect and confirm whether the issue is covered under their workmanship guarantee, a product warranty, or both.
Written communication is best because it creates a record. Keep the tone factual and give them a reasonable opportunity to inspect and remedy the issue.
Step 3: Give them a chance to fix it
In many cases, a reputable plumber will return promptly and correct genuine defects. If they agree the problem is theirs, ask them to confirm:
- what they will repair
- when they will do it
- whether any associated damage will be addressed
- whether the repair is covered at no additional cost
Step 4: Escalate if they do not resolve it
If the plumber refuses, delays unreasonably or says the fault is not theirs when you disagree, your next steps may include:
- getting an independent plumbing opinion or report
- checking whether the issue involves the manufacturer or supplier
- making a formal written complaint to the company director or owner
- using a disputes process, mediation or the Disputes Tribunal for lower-value claims
- seeking legal advice for larger or more complex losses, especially where water damage is significant
If the work involves a licensing or compliance issue, you can also consider whether the matter should be raised with the relevant authority.
Licensing, compliance and who can do what
In New Zealand, plumbing, gasfitting and drainlaying are restricted trades regulated by the Plumbers, Gasfitters and Drainlayers Board (PGDB). That means the person carrying out the work must be appropriately licensed, or the work must fit within the very limited scope of work that can be done by an unlicensed person.
When comparing plumbers, check:
- their licence status with the PGDB
- whether they are the correct licence holder for the job, especially if it involves gas or drainage
- whether they are insured
- whether they can provide a producer statement or compliance paperwork where relevant
Some plumbing projects may also overlap with other regulated work:
- Electrical work connected to pumps, controls or hot water systems is regulated by the Electrical Workers Registration Board (EWRB) and must be done by a licensed electrician.
- Building work may require a building consent from the local council, especially where you are altering pipe penetrations, relocating sanitary fixtures, or doing work that affects structure or waterproofing.
A good plumber will flag when another trade, consent or inspection is needed rather than pretending it is all within their scope.
What a good plumbing quote should say
A detailed quote helps prevent arguments about guarantees later. Ask for written quotes from at least two or three tradespeople, especially for larger jobs such as bathroom renovations, hot water cylinder replacement or re-piping.
A solid quote should include:
- a clear scope of work
- what is excluded
- materials and brands to be used
- whether the price includes GST
- whether any council consent, testing or certification is included
- the workmanship guarantee period
- product warranty details for supplied items
- expected start and completion dates
- who will coordinate other trades
If a plumber is reluctant to put terms in writing, that is a red flag. The best tradespeople are usually happy to explain what is covered and what is not.
Red flags to watch for
Be cautious if a plumber:
- refuses to give written terms
- offers a very long guarantee but cannot explain exclusions
- says “warranty covers everything” without checking the product terms
- is vague about who is licensed to do the work
- cannot show proof of insurance or current licence details
- wants full payment upfront for a routine household job
- suggests ignoring consent or compliance requirements
These issues do not automatically mean the plumber is poor, but they do mean you should ask more questions before you sign anything.
How to protect yourself before work starts
Before you commit, make sure you have:
- checked the plumber’s licence and credentials
- asked for a written quote and guarantee terms
- confirmed which products are covered by manufacturer warranties
- asked whether the job needs council consent or another specialist trade
- kept copies of all emails, messages, invoices and manuals
- agreed on how defects will be reported and fixed
For seasonal work, such as hot water faults in winter or outdoor plumbing before heavy rain, it is especially important to book early. Demand can increase during colder months and after storms, which can affect pricing and wait times.
The bottom line
A plumber should offer more than a handshake promise. At minimum, you want a clear workmanship guarantee, transparent product warranty information and work that complies with the CGA and New Zealand licensing rules.
If a plumber is professional, they will explain exactly what they guarantee, what the manufacturer covers, and what happens if a defect shows up later. That clarity protects both sides and makes it much easier to sort out problems quickly if something goes wrong.
Master Plumbers
