Why guarantees matter when hiring a floor sander
Sanding and refinishing a timber floor is a specialist job. Done well, it can transform a home and add value. Done badly, it can leave you with gouges, uneven colour, visible sanding marks, bubbling finish, dust contamination, or a floor that wears out far too quickly.
That is why guarantees and warranties matter. They are not just sales talk — they are part of how you check that the person you hire is professional, accountable, and clear about what happens if something goes wrong.
For homeowners in New Zealand, the main protections are:
- the contractor’s own workmanship guarantee - product warranties from the coating or stain manufacturer - your rights under the Consumer Guarantees Act 1993 (CGA) - in some cases, the Fair Trading Act 1986 if the work was sold using misleading claims
A good floor sander should be prepared to explain all four.
The three types of protection you should ask about
It helps to separate the different promises involved in a flooring job. They are often mixed together, but they are not the same.
| Type of protection | Who provides it | What it covers | What to check | |---|---|---|---| | Workmanship guarantee | The floor sander or company | Faults caused by poor sanding, application, preparation or installation of the finish | Length, exclusions, how claims are made | | Product warranty | The manufacturer of the stain, sealer or topcoat | Defects in the product itself | Conditions, approved applicators, maintenance requirements | | Consumer Guarantees Act rights | The contractor and supplier under NZ law | Reasonable care and skill, fit for purpose, completion in reasonable time | Applies even if there is no written warranty |
A strong quote should make it clear which guarantees apply to the labour and which apply to the products.
What a workmanship guarantee should cover
A workmanship guarantee is the contractor’s promise that the job has been carried out properly. There is no standard nationwide format, so the details matter.
A sensible floor sanding workmanship guarantee should usually cover:
- sanding marks left visible through normal lighting - uneven finish or patchiness caused by poor preparation - streaking, bubbling or peeling caused by incorrect application - obvious lapses in dust extraction or clean-up that affect the finish - gaps caused by the contractor’s own mistakes in preparation or recoating - failure to follow the agreed system, such as the wrong sealer or topcoat
It should also state the duration of cover. For example, some contractors offer a 12-month workmanship guarantee, while others may give a longer period for specific defects. The period should be realistic and written down.
A proper guarantee should also explain:
- what is included and excluded - whether it covers timber movement, moisture problems or pre-existing damage - how quickly the contractor will inspect a complaint - whether they will repair, resand, refund, or use a combination of remedies - whether any limit applies if the floor was not maintained as instructed
Red flags in workmanship guarantees
Be cautious if a floor sander says their guarantee does not cover almost anything. Common exclusions that are reasonable on their own include:
- accidental damage after completion - water damage from leaks or flooding - heavy furniture dragged across the floor - moisture issues already present in the subfloor or timber - normal wear and tear in high-traffic areas
However, if the guarantee excludes all defects, all finish failures, or all consequences of “site conditions” without any explanation, that is not very useful. Ask them to spell out exactly what they mean.
What product warranties usually apply to sanding and finishing
Most floor sanding jobs involve coatings, stains, primers, fillers, or sealers. These products often come with their own manufacturer warranty or technical guarantee.
That warranty may cover things like:
- product defects - premature failure of the coating under normal use - delamination or adhesion problems where the product was applied correctly
But product warranties often come with conditions, such as:
- the product must be used exactly as specified by the manufacturer - the applicator must be trained or approved - the timber moisture content must be within range - the floor must be maintained with approved cleaners only - the warranty may be limited to replacement product rather than labour
This is important for homeowners because a product warranty does not automatically fix poor workmanship. If the sanding prep was wrong, the manufacturer may refuse the claim, leaving the contractor responsible instead.
Ask for the product names and systems
Before the work starts, ask for:
- the brand and type of sealer, stain and topcoat - the number of coats proposed - whether water-based or solvent-based coatings will be used - any maintenance instructions and recoat advice - the warranty documents or product data sheets
If a contractor cannot tell you the exact products they intend to use, that is a warning sign. You cannot assess the warranty properly without knowing what is being applied to your floor.
Your rights under the Consumer Guarantees Act
Even if a contractor does not offer a written guarantee, the Consumer Guarantees Act still applies when you hire them as a consumer in New Zealand.
Under the CGA, services must be carried out:
- with reasonable care and skill - in a reasonable time if no time is agreed - for a reasonable price if no price is agreed - in a way that is fit for the purpose you told them about, or that is implied by the job
For floor sanding, that means the job should be done to a professional standard. The finish should match what was agreed or reasonably expected, and the contractor should use suitable methods and materials.
If the work is faulty, the CGA may allow you to require the contractor to fix it. If the failure is substantial or cannot be remedied, you may be entitled to:
- have the service redone - have the issue fixed by someone else and recover reasonable costs in some situations - seek a price reduction - cancel the contract in serious cases
The CGA cannot be contracted out of in ordinary consumer situations, so a written quote saying “no warranties” does not wipe out your rights.
How to judge whether a warranty or guarantee is worth anything
A guarantee is only useful if it is backed by a contractor who is organised and financially stable enough to stand behind it.
When comparing quotes, look for these practical signs of reliability:
- the quote is written and itemised - the contractor clearly describes preparation, sanding grits, coating system and drying times - the company has a physical NZ address and active contact details - they are happy to show references or recent local work - they explain what happens if the finish fails early - they carry public liability insurance - they understand the timber species and conditions common in NZ homes
In New Zealand, humidity and seasonal changes matter. Floors sanded in a hot, dry Canterbury summer may behave differently from those finished in a damp Auckland winter or a cooler Wellington property with less airflow. A good contractor should talk about moisture, curing times and ventilation, not just promise a quick turnaround.
Questions to ask before you accept the quote
Use your quote comparison to test how much the contractor stands behind their work. Ask:
- What workmanship guarantee do you offer, and for how long? - Does the guarantee cover sanding defects, finish application, and dust contamination? - Which product warranties apply, and who provides them? - What maintenance is required to keep the warranty valid? - What happens if the floor needs to be repaired after completion? - Will you inspect and respond in writing if there is a complaint? - Are any exclusions tied to moisture, subfloor conditions or previous coatings? - Do you provide the guarantee and product details on the invoice or contract?
A contractor who answers clearly and in writing is usually easier to deal with if there is a problem later.
What to do if the floor sanding work is faulty
If you notice a problem, act promptly. Delays can make disputes harder to resolve, especially if the floor has been used, cleaned, or covered in a way that changes the evidence.
Step 1: Document the issue
Take clear photos and, if useful, short videos in natural light and indoor lighting. Note:
- when the work was completed - when you first noticed the problem - what the defect looks like - any recent cleaning, furniture movement or water exposure
Keep the contract, invoice, quote, guarantee documents and product details.
Step 2: Notify the contractor in writing
Send a calm, specific email or message. Explain the fault and what remedy you want. For example, you might ask for:
- an inspection - a resand and recoating - a partial refund - a professional repair by the original contractor
Be reasonable and give them a chance to inspect. Many disputes are solved at this stage.
Step 3: Escalate if needed
If the contractor refuses to help or does not respond, you can consider:
- making a formal written complaint under the CGA - seeking advice from Consumer Protection or Citizens Advice Bureau - checking whether the company is a member of any trade association with a complaints process - using the Disputes Tribunal for lower-value disputes, if appropriate
For larger or more technical jobs, you may need an independent flooring inspector or another qualified tradesperson to assess the defect. Their report can help if the matter goes further.
What recourse you may have if the contractor disappears or refuses to fix it
If the company is unresponsive, your options depend on the facts and the amount at stake.
You may be able to:
- rely on the CGA and demand a remedy - claim through the Disputes Tribunal for financial losses within its jurisdiction - pursue a breach of contract claim in the District Court for bigger matters - make a complaint to the Commerce Commission if misleading claims or conduct are involved
If the work has caused damage beyond the floor itself — for example, skirting boards, cabinetry, or adjoining finishes — keep records of those costs too.
How to protect yourself before the job starts
A good guarantee starts before the first sanding pass. To reduce the risk of disputes:
- get at least two or three written quotes - compare the scope, not just the price - ask exactly what prep work is included - confirm who supplies the products and whether they are covered by warranty - get the guarantee terms in writing before work begins - ask whether moisture testing will be done if needed - make sure the quote states how long the job may take, including drying time
This is especially important in busy periods, such as pre-Christmas renovations or the spring property market, when some contractors may be tempted to rush jobs between bookings.
The bottom line
A reliable floor sander in New Zealand should be willing to stand behind both their workmanship and the products they use. You want a clear written guarantee, the relevant product warranty details, and confidence that the contractor understands their obligations under the Consumer Guarantees Act.
If something goes wrong, you are not powerless. Document the issue, notify the contractor promptly, and use the CGA and dispute resolution pathways if needed. The best protection, though, is choosing carefully at the start: compare written quotes, check references, and do not be afraid to ask direct questions about guarantees before you sign anything.