Swapping out an old or leaking shower head is one of the most beginner-friendly plumbing jobs a homeowner can tackle. No special licences are required, and with the right tools you can have a new shower head installed and running in well under half an hour. Here's everything you need to know to do it safely and correctly.
Is Replacing a Shower Head Restricted Work in NZ?
In New Zealand, replacing a shower head on an existing arm (the pipe that sticks out of the wall) is generally considered routine maintenance and does not require a licensed plumber. You are simply unscrewing one fitting and screwing on another — no pipework is being altered.
However, if the job involves moving or extending the shower arm, altering supply pipes inside the wall, or installing a new shower system from scratch, that becomes restricted sanitary plumbing work under the Plumbers, Gasfitters and Drainlayers Act 2006. That work must be carried out by a licensed tradesperson registered with the Plumbers Gasfitters & Drainlayers Board. When in doubt, check with a professional.
Tools and Materials You'll Need
Gather everything before you start:
Choosing the Right Shower Head
Most NZ shower arms use a standard ½-inch BSP (British Standard Pipe) thread, so the majority of shower heads sold here will fit. When shopping, consider:
| Feature | What to Look For |
|---|---|
| Water efficiency | WELS rating — 3 stars or higher saves water and money |
| Flow rate | Lower litres-per-minute = lower hot water costs |
| Spray modes | Single, massage, mist — choose what suits your household |
| Finish | Chrome, brushed nickel, matte black — match your existing fittings |
| Arm compatibility | Fixed wall arm vs. rail/hose combo |
If you're a landlord, note that Tenancy Services Healthy Homes standards require adequate hot water, so a very low-flow head may not always be appropriate.
Step-by-Step: How to Replace Your Shower Head
Step 1 — Turn Off the Water
You do not need to turn off the mains for this job. Simply make sure the shower mixer or taps are in the off position. It's still a good idea to know where your home's toby (water meter shutoff) is, just in case.
Step 2 — Remove the Old Shower Head
Wrap a cloth around the shower arm to protect the finish, then use your adjustable spanner to grip the collar or nut at the base of the shower head (not the arm itself). Turn anticlockwise to loosen. Once loose, unscrew by hand. If it's stuck due to mineral build-up, apply a little white vinegar and wait 10–15 minutes before trying again.
Step 3 — Clean the Threads
Once the old head is off, inspect the shower arm threads. Remove any old PTFE tape or debris with a cloth. If there's significant limescale, a brief soak with a descaler will help. Clean threads ensure a leak-free seal.
Step 4 — Apply PTFE Tape
PTFE tape is the key to a watertight connection. Wrap the tape clockwise around the male threads of the shower arm (clockwise when looking at the end of the arm) — this way it won't unwind when you screw the head on. Apply 2–3 snug layers, overlapping as you go.
Step 5 — Attach the New Shower Head
Screw the new shower head on by hand first, turning clockwise. Once hand-tight, use your spanner to snug it up — typically just a quarter to half a turn beyond hand-tight. Do not overtighten, as this can crack plastic fittings or damage the thread.
Step 6 — Test for Leaks
Turn the shower on and check the connection point carefully. A small drip usually means you need slightly more PTFE tape or another quarter-turn with the spanner. If it leaks persistently, remove the head, re-tape, and refit.
Tips for a Long-Lasting Result
- Hard water areas (common in parts of Canterbury and Hawke's Bay) cause faster mineral build-up — choose a shower head with rubber nozzles you can rub clean.
- Never use excessive force on the shower arm — if it's old copper or corroded, you risk snapping it inside the wall, which then becomes a plumber's job.
- If your water pressure seems low after fitting the new head, check whether it has a built-in flow restrictor that can be adjusted.
When to Call a Professional
Call a licensed plumber if you encounter any of the following:
- The shower arm is corroded, cracked, or snaps during removal
- There is water damage or mould visible around the wall fitting
- You want to relocate the shower head or install a new overhead (ceiling) rose requiring pipework changes
- You're installing a new thermostatic or digital shower system
- You're unsure about any step of the process
A qualified local plumber can be found quickly on tradedirectory.co.nz. For guidance on what work requires a licensed plumber, MBIE Building Performance has clear information on restricted building and plumbing work.