Why guarantees and warranties matter when hiring a plasterer
Plastering can look straightforward, but the quality of the finish has a big impact on the look, durability and value of your home. Poor workmanship can lead to visible cracking, uneven surfaces, delamination, damp-related issues and costly rework. That is why it is worth asking every plasterer what guarantees and warranties they offer before you accept a quote.
In New Zealand, the best protection comes from understanding three separate things:
- the plasterer’s own workmanship guarantee
- any manufacturer’s product warranty on plaster, sealants, membranes or coatings
- your legal rights under the Consumer Guarantees Act 1993 (CGA)
A good plasterer should be upfront about all three. If they are vague, reluctant to put anything in writing, or promise “lifetime” cover without explaining the limits, treat that as a warning sign.
Workmanship guarantees: what a plasterer is actually promising
A workmanship guarantee is the plasterer’s promise that their labour will meet an agreed standard. It is separate from the products used. For example, a plasterer might guarantee that internal stopping, skim coating or rendering work will be free from defects caused by poor application for 12 months, 2 years, or another period stated in writing.
A sensible workmanship guarantee should spell out:
- the length of the guarantee period
- what types of defects are covered
- what is excluded
- how to make a claim
- whether the guarantee follows the property or only the original client
- whether the plasterer will repair, rework or refund
Typical workmanship issues might include:
- visible cracking beyond normal hairline settlement cracks
- debonding or hollow areas
- excessive shrinkage or ridging
- poor sanding or finishing
- uneven surfaces that do not meet the agreed finish level
- failure to prepare the substrate properly
Be careful with broad claims like “lifetime workmanship warranty”. Ask what “lifetime” means. Sometimes it refers to the life of the product, the contract, or the original owner only. A clear, realistic written guarantee is more useful than a flashy slogan.
Product warranties: what the materials may cover
Plasterers often use a range of materials: bagged plaster compounds, jointing systems, renders, textured coatings, sealers, primers, waterproofing products and mesh reinforcement. Many of these products come with manufacturer warranties, but those warranties do not automatically cover the plasterer’s labour.
Product warranties can cover defects such as:
- premature failure of a compound or coating
- product not performing as specified when applied correctly
- manufacturing faults in the material itself
However, most product warranties only apply if:
- the product was installed exactly to the manufacturer’s instructions
- the substrate was suitable
- the product was used within its intended scope
- the work was done by a competent applicator
- the warranty registration or proof of purchase is kept
That means a product can fail for reasons outside the manufacturer’s responsibility, including poor surface preparation, weather exposure, moisture ingress, or incorrect mixing and curing. The plasterer should tell you which products they are using and provide the product data sheets or warranty documents if requested.
For exterior work, this matters even more. In New Zealand’s variable climate, timing and weather protection are critical. Rain, high humidity, cold snaps and strong winds can all affect curing and finish quality. A good plasterer will explain any weather-related limits and may build that into their guarantee.
The Consumer Guarantees Act and plastering work in NZ
The Consumer Guarantees Act 1993 applies to most services supplied to homeowners in New Zealand, including plastering. Under the CGA, services must be:
- carried out with reasonable care and skill
- fit for the purpose you told the trader about, or that is otherwise made known
- completed within a reasonable time if no timeframe is agreed
- supplied at a reasonable price if no price is set
This is important because even if a plasterer offers only a short workmanship guarantee, your CGA rights can still apply if the work is faulty.
In practice, that means if the plastering is not done with reasonable care and skill, you may be entitled to have the problem fixed. If the failure is substantial, you may be able to reject the service and seek a refund, replacement or compensation depending on the circumstances.
The CGA cannot usually be signed away by a plasterer, so do not be reassured by a contract that tries to limit your rights too heavily. A business can offer additional guarantees, but it cannot contract out of the CGA for ordinary residential home-improvement work in a way that removes your statutory protections.
What a good plasterer’s written guarantee should include
Ask for the guarantee and quote in writing before work starts. A proper document should be specific, not generic. The table below shows the key things to look for.
| Item | What to check | Why it matters |
|---|---|---|
| Scope of work | Exactly which areas and surfaces are covered | Avoids arguments about what was included |
| Standard of finish | Agreed finish level, texture and acceptable tolerances | Sets expectations for appearance and flatness |
| Warranty period | How long workmanship is covered | Helps you know when a claim can be made |
| Product details | Brand, product name and whether manufacturer warranty applies | Separates material faults from labour faults |
| Exclusions | Moisture damage, movement, impact damage, poor ventilation, substrate issues | Prevents unrealistic claims |
| Maintenance obligations | Cleaning, recoating, resealing, ventilation | Some finishes need ongoing care |
| Claim process | Who to contact and what evidence is needed | Makes it easier to resolve issues quickly |
| Remedy | Repair, rework, refund or partial refund | Clarifies what happens if the work fails |
If the plasterer says “standard warranty applies”, ask them to define it. Standards are only useful when they are written down.
Questions to ask before you accept a quote
Getting multiple written quotes is one of the best ways to compare not just price, but also the level of protection on offer. Ask each plasterer these questions:
- How long is your workmanship guarantee?
- What exactly does it cover?
- What is excluded?
- Which products will you use, and do they have manufacturer warranties?
- Will you provide copies of the product warranty documents?
- Do you carry public liability insurance?
- Are you experienced with the specific type of plastering I need, such as interior stopping, solid plaster, decorative plaster, EIFS or exterior render?
- What surface preparation will you do before plastering?
- What happens if cracking or delamination appears after completion?
- Will you return to inspect and repair issues within a set timeframe?
It is also sensible to check references and recent jobs, particularly for exterior plastering or work in older homes where moisture, movement and substrate condition can be a concern.
When plastering work may need consent or other compliance checks
Not every plastering job needs building consent, but some do. In New Zealand, whether consent is required depends on the scope of work and how it affects the building’s structure, weather-tightness, fire performance or other regulated aspects.
Examples where you should check with your local council before starting include:
- significant alterations to exterior cladding systems
- repairs that affect weather-tightness or a building’s weathertight envelope
- work connected to renovations that include structural changes or other consented building work
A plasterer should not promise that consent is unnecessary if the job is borderline. If in doubt, ask the council or a qualified building professional. Also remember that some related trades are separately regulated in New Zealand: plumbing, gasfitting and drainlaying are restricted work under the PGDB, and electrical work is regulated by the EWRB. A plasterer may work alongside those trades on a renovation, but should not be carrying out regulated work outside their scope.
Warning signs that a plasterer’s guarantee is weak
Not all guarantees are equal. Be cautious if a plasterer:
- refuses to provide any guarantee in writing
- gives only verbal assurances
- offers a warranty but excludes almost everything important
- will not name the products being used
- refuses to specify cure times or weather restrictions
- says “no cracks ever” or makes other unrealistic promises
- wants full payment before inspection or completion without clear milestones
Also be wary of unusually low prices. In a market where labour, materials and access costs have all risen, a very cheap quote may mean shortcuts in preparation, product quality or aftercare. A low price is not a bargain if the finish fails and you must pay another crew to fix it.
What to do if the plastering is faulty
If you think the work is defective, act promptly and keep records. Good evidence makes a dispute much easier to resolve.
Step 1: Document the problem
- take dated photos and videos
- note when the issue first appeared
- keep copies of the quote, invoice, contract and any messages
- record the product names if you know them
- note weather conditions if the issue is on exterior work
Step 2: Notify the plasterer in writing
Describe the defect clearly and ask for an inspection and remedy. Be specific about what you want: repair, rework, or another appropriate solution. Many issues are resolved more quickly when raised early and calmly.
Step 3: Refer to the guarantee and the CGA
If the work is within the workmanship guarantee period, quote that clause. If not, you may still have rights under the Consumer Guarantees Act if the service was not carried out with reasonable care and skill.
Step 4: Escalate if needed
If the plasterer refuses to respond or disputes the fault, consider:
- a formal written complaint
- mediation or dispute resolution services
- legal advice, especially for higher-value claims
- the Disputes Tribunal for smaller claims, if eligible
If the issue affects a wider renovation, it may also be worth getting an independent building inspection or a report from another plasterer to confirm the cause and likely remedy.
How to protect yourself before the job starts
The best time to deal with warranty problems is before the first trowel goes on the wall. To reduce risk:
- get at least two or three written quotes
- compare scope, not just price
- ask for the guarantee in writing
- confirm the products and their warranties
- check the plasterer’s experience with your type of job
- agree on preparation, curing times and site protection
- keep all paperwork, including receipts and photos
If the work is on an exterior wall or in a home prone to dampness, ask how the plasterer will handle ventilation, drying conditions and moisture checks. In New Zealand homes, especially in older or leaky buildings, underlying moisture issues can make a “plaster failure” look like a workmanship problem when the real cause is elsewhere.
The bottom line
A reputable plasterer in New Zealand should offer more than a vague promise. You want a written workmanship guarantee, clear product warranty information, and a contract that acknowledges your rights under the Consumer Guarantees Act. The best tradespeople are upfront about what is covered, what is not, and how defects will be fixed.
If a plasterer is professional, they will welcome your questions, provide documentation, and explain the practical limits of their guarantee. That transparency is often the strongest sign you are hiring the right person for the job.
Master Painters NZ member
