Why guarantees matter when hiring a glazier
Glass work can look simple from the outside, but a poor install can lead to leaks, draughts, cracked panes, failed seals, condensation, safety hazards and expensive call-backs. In New Zealand, where weather can shift quickly and coastal conditions are tough on materials, a proper guarantee is a practical safeguard rather than a nice extra.
A good glazier should be able to explain, in writing, what is covered if something goes wrong, how long the cover lasts, and who to contact if there is an issue. If they are vague, that is a warning sign.
When comparing quotes, don’t just look at the total price. Ask what guarantees are included, what the exclusions are, and whether the work is backed by the installer, the manufacturer, or both.
The three layers of protection you should look for
For glazing work, there are usually three separate protections:
| Type of protection | What it covers | Who provides it | Typical duration | |---|---|---|---| | Workmanship guarantee | Faults caused by the glazier’s installation | The glazier or glazing company | Often 1–5 years, sometimes longer | | Product warranty | Defects in the glass, sealant, hardware, frames or fittings | The manufacturer or supplier | Varies by product; check the warranty terms | | Consumer Guarantees Act rights | Goods and services must be of acceptable quality and carried out with reasonable care and skill | Law, not a business promise | Applies automatically, subject to normal legal time limits |
These protections can overlap. For example, a failed double-glazed unit may be covered by a product warranty if the seal failed due to a manufacturing defect. If the unit was installed badly and water entered through poor sealing, the glazier’s workmanship guarantee may be the more relevant remedy. If the job was not done with reasonable care and skill, the Consumer Guarantees Act (CGA) may also apply.
What a workmanship guarantee should cover
A workmanship guarantee is the installer’s promise about the quality of their labour. This is one of the most important things to ask for because many glazing problems are caused by installation issues rather than the glass itself.
A solid workmanship guarantee should clearly state that it covers defects arising from the glazier’s work, such as:
- incorrectly fitted glass or glazing beads - leaking around showers, windows, splashbacks or balustrades - inadequate sealing or weatherproofing - rattling, movement or poor alignment - damage caused during installation - failure to meet the agreed specification - issues caused by poor finish, such as visible gaps, uneven silicone, or loose fixings
It should also explain what is not covered. Common exclusions include:
- accidental damage after completion - damage caused by building movement, subsidence or earthquake events - failures caused by other trades after the glazing work is complete - normal wear and tear - misuse, neglect, or cleaning with unsuitable chemicals
Ask whether the guarantee is transferable if you sell the house. Some are tied to the original homeowner, while others stay with the work at the property.
What product warranties usually cover
Product warranties sit with the glass or hardware manufacturer, not necessarily the installer. They are especially relevant for double glazing, showers, mirrors, commercial glass, frameless systems, and specialist hardware.
Common products with warranties include:
- insulated glass units - toughened or laminated safety glass - window and door seals - hinge and fixing hardware - shower enclosures and fixtures - mirror backing and edge treatments - sealants and adhesives, depending on the brand
Read the warranty carefully. Some warranties only apply if the product is installed by an approved installer and maintained correctly. Others exclude coastal locations, industrial environments, or areas with high moisture exposure unless a specific product grade was chosen.
In New Zealand, that matters because a property in a high-wind or salt-laden coastal zone may need different materials than a sheltered inland home. A good glazier should match the product to the environment and tell you if that affects the warranty.
The Consumer Guarantees Act: your baseline protection
The Consumer Guarantees Act 1993 is important because it applies automatically to most residential glazing jobs. A business cannot contract out of it for ordinary household use.
Under the CGA, the goods and services provided must be:
- of acceptable quality - fit for purpose - supplied with reasonable care and skill - completed within a reasonable time, if no time is agreed - consistent with any description, sample, or demonstration
For a homeowner, that means a glazier should not only install the glass properly, but also use suitable materials and complete the work to a standard a reasonable person would expect.
If the work is faulty, the CGA generally gives you the right to have it fixed. If the fault is substantial or cannot be remedied within a reasonable time, you may be able to reject the service or seek compensation for the loss caused.
The key point: a business warranty is extra protection, not a replacement for your CGA rights.
What to ask before you accept a quote
Always get multiple written quotes. For glazing, quotes can differ because of glass thickness, safety requirements, frame condition, hardware quality, access issues, and whether the job is straight replacement or part of a larger repair.
Before you sign, ask the glazier these questions:
- What workmanship guarantee do you provide, and for how long? - Is the guarantee in writing? - Does the warranty cover both labour and materials, or just one of them? - Who handles claims: you, the supplier, or both? - What maintenance is required to keep the warranty valid? - Are there exclusions for coastal properties, showers, or exterior glazing? - If a product fails, will you organise the replacement, or will I need to contact the supplier? - Does the quote include removal and disposal of old glass? - Will the finished work meet NZ Building Code requirements and any relevant safety standards?
Also confirm whether the work may require consent or other approvals. Most simple like-for-like glass replacement does not need building consent, but larger alterations can. For example, changing an opening, modifying structural elements, or installing some balustrades or safety-glass systems may involve building consent or specific compliance obligations. Your glazier should flag this early, but if the job is part of a renovation, check with your local council or your builder.
Warning signs that a glazier’s warranty may not be reliable
A promise is only as good as the paper behind it. Be cautious if a glazier:
- refuses to give warranty terms in writing - gives a very short guarantee without explaining why - says “don’t worry, we’ll sort it” but won’t specify what is covered - excludes nearly everything except obvious manufacturing defects - will not identify the product brand or supplier - will not provide a tax invoice or business contact details - pressures you to pay in cash only
It is also worth checking they have the right experience for the job. A shower screen, a heritage villa window repair, a large commercial frontage, and a frameless balustrade all have different technical demands. The right guarantee means more when the installer has the right expertise.
If the work is faulty, what are your options?
If you spot a problem, act quickly and keep records.
Step 1: Document the issue
Take clear photos or video of the fault. Note when you noticed it, whether it is getting worse, and any weather conditions that may be relevant. Keep copies of the quote, invoice, texts, emails and warranty documents.
Step 2: Notify the glazier promptly
Contact the business in writing and explain the problem clearly. Include:
- your name and address - the job date and invoice number - a description of the fault - photos - what remedy you want, such as repair, replacement, or a refund if appropriate
A good business will usually inspect the issue and offer a remedy. Give them a reasonable opportunity to fix it, unless the fault is urgent or unsafe.
Step 3: If needed, rely on your CGA rights
If the problem is not resolved, you can refer to your rights under the Consumer Guarantees Act. You can ask for the service to be remedied at the supplier’s cost, or in some cases seek a refund or damages.
Step 4: Escalate if necessary
If the business still will not respond, options may include:
- making a formal complaint in writing - contacting your payment provider if you paid by card and the circumstances support a chargeback request - using Disputes Tribunal for smaller claims - getting advice from Citizens Advice Bureau or Consumer Protection - seeking legal advice for larger or complex claims
Keep in mind that if the work relates to building performance or defects that may affect compliance or safety, you should not ignore the issue just because the warranty period has expired. Some problems may still be covered by statutory rights depending on the circumstances.
How to compare guarantees between quotes
Not all guarantees are equal. A cheaper quote may look attractive until you see it only includes a short labour warranty and no help with manufacturer claims.
When comparing quotes, check whether each one states:
- the exact scope of work - the product brand and specifications - workmanship warranty length - product warranty details - who is responsible for follow-up - whether after-hours call-outs or remedial visits are included - any exclusions that might matter to your property
If one quote is much cheaper, find out why. It may be a sign of lower-grade glass, a shorter guarantee, less preparation, or fewer inclusions. Ask for the difference in writing so you can compare like with like.
Practical tips for NZ homeowners
Because New Zealand homes face a mix of damp winters, strong UV, salt air, and in some regions significant wind exposure, long-term performance matters as much as price.
Before accepting a glazing job:
- get at least three written quotes for larger jobs - check the company has a proper business identity and contact details - ask for the exact product brand and specification - confirm whether the work needs building consent or council sign-off - keep all paperwork in one place - inspect the finished work before making the final payment
For exterior glazing, ask how the installation handles local conditions. In coastal areas, corrosion resistance and seal durability can be just as important as the glass itself. For showers and bathrooms, ventilation and correct sealing are crucial to preventing mould and premature failure.
The bottom line
A trustworthy glazier should stand behind both their labour and the products they install. In New Zealand, the best protection comes from a combination of a clear workmanship guarantee, genuine manufacturer warranties, and your rights under the Consumer Guarantees Act.
The smartest approach is simple: get multiple written quotes, check credentials, ask detailed questions about warranty coverage, and insist on paperwork before work begins. If the job goes wrong, act quickly, keep records, and make your complaint in writing so you have the best chance of a fair outcome.