The short answer is no — installing a flued gas heater in your New Zealand home is restricted work under the Gas Act 1992 and must be carried out by a licensed gasfitter. Attempting to do it yourself is illegal, potentially dangerous, and could void your home insurance. Here's everything you need to understand before your heater goes in.
What Is a Flued Gas Heater?
A flued gas heater is a gas heating appliance connected to a flue (duct or pipe) that vents combustion gases — including carbon monoxide — safely outside your home. Common types include:
- Natural draught flued heaters — rely on natural convection to draw exhaust gases up and out
- Balanced flue (room-sealed) heaters — draw combustion air from outside and vent exhaust outside through a co-axial flue, making them very safe for indoor air quality
- Fan-assisted flued heaters — use a powered fan to push exhaust gases out
Flued heaters are generally considered safer than unflued (flueless) gas heaters because combustion byproducts don't enter your living space — but only when they are correctly installed.
Why Is Installation Restricted Work?
Under the Gas Act 1992 and its regulations, any work that involves connecting, disconnecting, or altering gas fittings — including installing a flued gas heater and its gas supply connection — is restricted work. Only a person registered and licensed by the Plumbers, Gasfitters and Drainlayers Board (PGDB) is legally permitted to carry out this work.
This isn't just red tape. Incorrectly installed gas appliances can cause:
- Carbon monoxide poisoning — a colourless, odourless gas that can be fatal
- Gas leaks and fire or explosion risk
- Incomplete combustion leading to soot, poor air quality, and appliance damage
WorkSafe NZ treats gas safety incidents seriously, and the consequences of unlicensed gas work can include prosecution, fines, and — most importantly — serious harm to your family.
What Work Is Involved in a Flued Heater Installation?
A typical flued gas heater installation involves several steps, most of which are restricted:
| Task | Who Can Do It? |
|---|---|
| Connecting appliance to gas supply | Licensed gasfitter only |
| Installing or modifying gas pipework | Licensed gasfitter only |
| Flue installation and penetration through walls/roof | Licensed gasfitter (may involve a builder for structural work) |
| Electrical connection (if hardwired) | Licensed electrician (EWRB) |
| Choosing heater location and preparing the space | Homeowner can assist/plan |
| Purchasing the appliance | Homeowner |
As a homeowner, you can research heater models, prepare the room, and purchase the unit — but the actual gas connection and flue work must be handed over to a qualified professional.
Do You Need a Building Consent?
This depends on the scope of work. Installing a flued heater often involves penetrating an external wall or ceiling/roof for the flue, which may require a building consent depending on your local council's interpretation and the nature of the work. Some installations may qualify as Schedule 1 exempt work under the Building Act 2004, but this is not guaranteed.
Always check with your local council before work begins. You can find guidance on consent requirements at MBIE Building Performance. Your licensed gasfitter will also be familiar with local requirements and can advise you.
NZ Building Code Considerations
Flued gas heater installations must comply with the NZ Building Code, particularly:
- Clause G11 (Gas as an Energy Source) — note: confirm the exact clause reference with your gasfitter or MBIE, as gas appliance requirements may sit under a different clause designation — covers safe use of gas appliances
- Clause G12 (Water Supplies) — not directly relevant but your gasfitter will be across all relevant clauses
- Clause E2 (External Moisture) — any wall or roof penetration for the flue must be properly weatherproofed to prevent moisture ingress
Your gasfitter should ensure the installation meets all relevant code requirements. BRANZ is a good resource for understanding building performance standards in NZ.
Natural Gas vs LPG — Does It Matter?
Yes. Whether your home is connected to natural gas (reticulated mains) or uses LPG (bottled gas), the installation is still restricted work. LPG installations have additional considerations around cylinder placement, ventilation, and regulator sizing — all handled by your licensed gasfitter.
Healthy Homes and Rental Properties
If you're a landlord, note that the Healthy Homes Standards set requirements for heating in rental properties. A correctly installed, appropriately sized flued gas heater may help meet the heating standard, but the appliance must be professionally installed and compliant. Check the Tenancy Services website for current requirements.
When to Call a Professional
For any flued gas heater installation, always engage a licensed gasfitter. Look for someone with a current practising licence — you can verify this on the PGDB website. If the installation involves hardwired electrical components (such as a thermostat or fan), a licensed electrician registered with the EWRB must carry out that portion of the work.
A good gasfitter will:
- Help you choose the right heater size and type for your space
- Ensure the flue is correctly routed and weatherproofed
- Test for gas leaks and commission the appliance
- Provide you with a Certificate of Compliance for the gas work
You can find qualified, local gasfitters in your area right here on tradedirectory.co.nz.
Sources & Further Reading
- Plumbers, Gasfitters and Drainlayers Board — Verify a licence
- WorkSafe NZ — Gas safety information
- MBIE Building Performance — Building consents and exempt work
- BRANZ — Building performance and compliance
- Tenancy Services — Healthy Homes Standards
- Electrical Workers Registration Board — Find a licensed electrician
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