When something goes wrong with your water, gas or drainage, knowing which tradesperson to call can save you time, money and stress. In New Zealand, plumbing, gasfitting and drainlaying are three distinct licensed trades — and while some practitioners hold qualifications in more than one area, they are legally separate disciplines. Here's what you need to know.
What Does a Plumber Do?
A plumber works on the pipework that supplies fresh (potable) water to your home and removes wastewater from fixtures. Their work typically includes:
- Installing and repairing hot and cold water supply pipes
- Fitting tapware, toilets, showers, baths and sinks
- Installing hot water cylinders and heat pumps (water-side connections)
- Connecting dishwashers and washing machines to water supply
- Fixing leaks in internal water supply pipes
- Roof plumbing (spouting, downpipes and flashings in some contexts)
Plumbing work in New Zealand is restricted work under the Plumbers, Gasfitters and Drainlayers Act 2006, meaning it must be carried out or supervised by a licensed practitioner registered with the Plumbers, Gasfitters and Drainlayers Board (PGDB). Always ask to see your tradesperson's licence before work begins.
What Does a Gasfitter Do?
A gasfitter installs, maintains and repairs natural gas and LPG (bottled gas) systems. Their work covers:
- Installing and connecting gas appliances (hobs, ovens, heaters, BBQ points)
- Running gas pipework inside and outside the home
- Installing and servicing gas hot water systems and boilers
- Pressure-testing gas lines and checking for leaks
- Commissioning and decommissioning gas systems
Gasfitting is also restricted work under NZ law. Attempting to connect or modify gas pipework yourself is not only illegal — it is extremely dangerous and could result in fire, explosion or carbon monoxide poisoning. Only a PGDB-licensed gasfitter may carry out this work. You can verify a tradesperson's licence on the PGDB website.
Safety note: If you smell gas, leave the building immediately, avoid operating any switches or appliances, and call your gas retailer's emergency line or 111.
What Does a Drainlayer Do?
A drainlayer works on the pipework that carries wastewater and stormwater away from your property, typically underground. Their work includes:
- Installing and repairing sewer drains from your home to the council connection
- Laying stormwater drains and soakage systems
- Installing septic tanks and on-site wastewater treatment systems
- CCTV drain inspections and drain unblocking (when it involves restricted drain work)
- Connecting new buildings to the public sewer network
Drainlaying is the third restricted trade under the PGDB. Because drains connect to the public wastewater network, councils require licensed drainlayers to carry out and certify this work.
How Do the Three Trades Compare?
| Trade | Main focus | Key systems | Licence required? |
|---|---|---|---|
| Plumber | Fresh water supply & internal wastewater | Pipes, taps, toilets, hot water | Yes — PGDB |
| Gasfitter | Gas supply & appliances | Natural gas, LPG pipework | Yes — PGDB |
| Drainlayer | Underground drainage | Sewer, stormwater, septic | Yes — PGDB |
Can One Person Hold All Three Licences?
Yes — and many do. A combination tradesperson may hold licences in two or all three disciplines. This is common in smaller towns and rural areas where one contractor needs to cover a range of work. When you contact a trade business, ask which licences they hold so you know exactly what they can legally do on your property.
What Can a Homeowner Do Themselves?
While restricted work must be done by a licensed professional, there are some minor tasks homeowners can legally carry out, such as:
- Replacing a tap washer or O-ring on existing tapware
- Unblocking a drain using a plunger or drain snake (surface-level blockages)
- Replacing a showerhead on an existing fitting
- Connecting a garden hose
However, anything involving cutting into pipework, connecting new fixtures, or touching gas lines must be left to a licensed tradesperson. When in doubt, call a professional — the cost of fixing unlicensed work (or the consequences of a gas leak) far outweighs the savings.
NZ Building Code Considerations
Plumbing and drainage work in New Zealand must comply with the NZ Building Code, particularly clauses G12 (Water Supplies) and G13 (Foul Water). For wet areas like bathrooms, clause E3 also applies. Most plumbing and drainage work requires a building consent from your local council, and the licensed tradesperson will typically manage this process. For more detail, visit MBIE Building Performance.
BRANZ also publishes useful technical guidance on plumbing and drainage best practice for NZ conditions.
When to Call a Professional
Call a licensed plumber if you have a burst pipe, no hot water, a dripping tap you can't fix yourself, or you're renovating a bathroom or kitchen. Call a licensed gasfitter for any gas appliance installation, suspected gas leak, or if you're adding a new gas connection. Call a licensed drainlayer if you have a blocked or broken sewer drain, are building a new home, or need a septic system installed or inspected.
You can find qualified, local plumbers, gasfitters and drainlayers on tradedirectory.co.nz — look for practitioners who display their PGDB licence details.