Choosing an insulation company is about more than just finding the lowest price. The right questions upfront will help you compare quotes fairly, avoid nasty surprises, and make sure the work meets New Zealand's building and tenancy requirements. Here's what to ask before you put pen to paper.
What Type of Insulation Do You Recommend, and Why?
There's no single "best" insulation product — the right choice depends on your home's construction, climate zone, and budget. Common options in NZ include:
- Glasswool batts (e.g., Pink Batts or similar) — widely used in ceiling and underfloor spaces
- Polyester batts — a non-itch alternative, good for DIY-friendly installs
- Blown-in loose fill — useful for hard-to-reach ceiling spaces or retrofitting
- Rigid foam board — often used in walls or under slabs
A reputable installer should explain why they're recommending a particular product for your specific situation, not just what they happen to stock. Ask them to reference the R-value (thermal resistance) they're proposing — BRANZ publishes guidance on recommended R-values for different NZ climate zones.
What R-Values Are You Quoting, and Do They Meet the NZ Building Code?
This is one of the most important questions you can ask. New Zealand's NZ Building Code clause H1 sets minimum energy efficiency requirements, and the required R-values vary depending on your region (NZ is divided into climate zones — confirm the current number and boundaries with MBIE Building Performance or your installer). Make sure the installer can tell you:
- The R-value for ceiling, underfloor, and wall insulation (if applicable)
- Whether those values meet or exceed current H1 requirements
- Whether a building consent is required for the work
For most insulation retrofits in existing homes, consent is not required under Schedule 1 exemptions — but always confirm this with your local council, as rules can vary.
You can check current Building Code requirements at MBIE Building Performance.
Are You Familiar With the Healthy Homes Standards?
If you're a landlord, insulation must meet the Healthy Homes Standards, which set specific R-value minimums for rental properties. Ask the installer:
- Whether the proposed insulation meets Healthy Homes requirements for your region
- Whether they can provide documentation you can keep for compliance records
More detail on what's required is available at Tenancy Services.
What Does the Quote Include — and Exclude?
Get clarity on exactly what's covered. A good quote should specify:
| Item | What to Confirm |
|---|---|
| Materials | Brand, product name, R-value, and quantity |
| Labour | Installation in all agreed areas |
| Access | How they'll reach ceiling/underfloor spaces |
| Removal | Whether old or damaged insulation will be removed |
| Clean-up | Will they leave the site tidy? |
| GST | Is it included in the quoted price? |
Also ask whether the quote covers any preparatory work — for example, if your underfloor space has moisture issues, that may need addressing before insulation goes in.
Are You Licensed or Accredited?
Insulation installation is not legally restricted work in the same way as electrical or plumbing, but accreditation still matters. Ask:
- Are you a member of the Insulation Association of New Zealand (IAONZ)?
- Are your installers trained and do they follow a recognised installation standard?
- Do you carry public liability insurance?
For any work that touches electrical wiring (such as maintaining clearances around downlights), the installer must be aware of safety requirements. If in doubt, a licensed electrician should be involved — check the Electrical Workers Registration Board for licensed practitioners.
What Warranties Apply — on Products and Workmanship?
Ask separately about:
- Product warranty — most reputable insulation products carry a manufacturer's warranty (often 50+ years for glasswool). Ask for the brand name so you can verify this.
- Workmanship warranty — what does the company guarantee about their installation, and for how long?
Get warranty details in writing before you sign.
How Will You Handle Moisture, Ventilation, or Existing Damage?
Installing insulation over existing problems can make things worse. A thorough installer should inspect your subfloor or ceiling space before quoting and flag any issues such as:
- Moisture or mould
- Damaged or missing vapour barriers
- Inadequate subfloor ventilation
- Pest damage
If they haven't inspected the space before quoting, ask how they'll handle unexpected issues on the day.
Can You Provide References or Examples of Similar Work?
A confident, experienced company should be happy to provide references from previous customers or show examples of similar projects. Online reviews are useful, but direct references let you ask specific questions about the experience.
When to Call a Professional
While some insulation work (such as laying batts in an accessible ceiling space) may be DIY-friendly, most homeowners benefit from using a qualified installer — particularly for underfloor work, blown-in insulation, or any job involving confined spaces. If your home was built before the 1990s, there may also be asbestos in older insulation or building materials; if you suspect this, stop work and contact a licensed asbestos assessor. WorkSafe NZ has guidance on managing asbestos safely.
You can find qualified local insulation installers on tradedirectory.co.nz.
