What counts as gasfitting
Under the Plumbers, Gasfitters, and Drainlayers Act 2006, gasfitting means fixing or unfixing gas pipes (flue and ventilation pipes included) and gas installations, making sure ventilation is adequate, and commissioning an installation so it runs safely.
In a home that covers a new gas hob or oven, a gas water heater or califont (the everyday name for gas continuous flow), a gas fire, extending or moving gas pipe, and tracking down a smell. Bottled LPG and piped natural gas are treated the same once the appliance is fixed in the house.
Times to get a gasfitter in
- You can smell gas near an appliance, the meter or a bottle. Leave first: see gas leaks.
- Burners that light unevenly, keep going out or won't stay lit.
- Soot or scorch marks around an appliance or its flue.
- You are replacing, adding or moving a gas appliance.
- You are selling and can't find the gas certificates for the house.
What a gasfitter will do
An authorised gasfitter will check the supply, pipework, flue and ventilation, do the work, then test and commission the installation.
Once the work is connected, the person who connects it, or their supervisor, issues a Gas Safety Certificate if they are satisfied the installation is safe. If they are not satisfied, the regulations say they must disconnect it from the gas supply immediately.
The two gas certificates
| Gas Safety Certificate | Certificate of Compliance (CoC) | |
|---|---|---|
| Needed for | All gasfitting, once the work is connected | General and high-risk gasfitting; optional for low-risk work |
| Issued by | The person who connects the work, or their supervisor | Someone who did or supervised the work and is authorised to certify that kind of gasfitting |
| Timing | No later than 20 working days after connection | General and high-risk work isn't complete until it is issued |
| What it tells you | The installation was safe to use when connected | What work was done, its safety status and who is responsible for it |
Low-risk, general or high-risk
WorkSafe sorts gasfitting into three risk classes. Swapping an appliance for an equivalent one, with no change to the pipework, flue, pressure, gas type, ventilation, energy use or operation, is low-risk. A brand-new installation is general. Adding to or altering an existing installation is high-risk, and the person who issues its CoC must record the job on the Electricity and Gas High-risk Database within 20 working days.
Under the Building Act, gas work counts as 'energy work', so a consent is rarely part of it. The gas certificates do that job instead: the Building Act calls them an Energy Works Certificate, and the Gas Safety Certificate counts as confirmation that the gasfitting meets the Building Code.
Who is allowed to do it
Certifying gasfitters can do all gasfitting, supervise others, and certify the work. The middle class, simply called Gasfitter since 1 April 2025 (it was 'Tradesman' before), can do the work under a named certifying supervisor but can't certify it. Restricted gasfitters can do gasfitting too, but they cannot connect a gas appliance to the supply. Some people hold a section 20 authorisation, which covers one specific area of gasfitting.
To check someone, search their first and last name on the PGDB register and look for the tick or green mark that shows a current licence. Ask who their supervisor is and check that name as well. Our guide to checking a PGDB licence walks through it.
The new self-certification scheme is for plumbing and drainlaying only. There is no gas version of it.
What you can and can't do with gas
You can
- Work on portable appliances with the bottle attached, such as a barbecue, cabinet heater or patio heater. PGDB still strongly recommends a gasfitter.
- Adjust the controls an appliance is designed for you to adjust.
- Keep your gas certificates safe: you may need them to sell, for insurance, or before a supplier will connect gas or refill LPG bottles.
Leave to an authorised tradie
- Installing, altering or repairing any gas appliance.
- Any gas pipe, flue or vent.
- Appliances fixed inside the house, even ones that run off gas bottles of any size.
- Testing, commissioning and certifying the installation.
The fines are higher for gas
Doing or helping with unauthorised gasfitting can bring a fine of up to $50,000 for an individual or $250,000 for a company. Knowingly employing, permitting or paying someone to do unauthorised gasfitting carries the same maximums. For plumbing and drainlaying, the top fine is $10,000.
Questions to ask the gasfitter
- Is your licence current, and does it cover gasfitting?
- Who is your certifying supervisor, if you have one?
- Is this low-risk, general or high-risk work?
- Will I get a Certificate of Compliance as well as the Gas Safety Certificate?
- What documents will I receive when the work is completed?
What we would do
Treat gas as a job you hand over in full. Before booking, ask which risk class the work falls in, because that tells you which certificates to expect, and don't pay the final bill until you know when they are coming. File them with the house papers; the next buyer or your insurer may ask. Whatever the appliance, tell us about it and we'll match you with an authorised gasfitter who works on that kind of installation.