How to install a new tap

🔧 How to install a new tap in Australia — trade guide for a straightforward replacement

What is involved in installing a new tap in Australia?

Plumbing work in Australia must be performed by a licensed plumber. This guide explains the process and helps you select the right tools and materials. Installing a new tap is a common upgrade in kitchens, bathrooms and laundries, but the method varies depending on whether you are replacing a mixer tap or separate pillar taps, and whether the tap is mounted to a basin, sink or benchtop.

This guide covers a typical tap replacement process for Australian homes, including isolation, removal, fit-off, reconnection and leak testing. For compliance, plumbing work should align with the Plumbing Code of Australia (PCA) and AS/NZS 3500, and any regulated plumbing work must be carried out by a licensed plumber in your state or territory.

What skill level is required for tap installation?

Beginner / Intermediate — Estimated time: 1 to 3 hours

What tools are essential for Australian tap installation?

🔧 Tools Required

What materials are needed for a new tap installation?

🪵 Materials

Safety Requirements

⚠️ Safety

Step-by-Step Guide

Step 1: Identify the tap type and mounting arrangement

1️⃣ Confirm the tap style

Work out whether you are installing:

Check the number of holes in the sink or basin and compare them to the new tap. A single-hole mixer usually suits one mounting hole, while a three-piece set needs separate penetrations.

Also confirm the connection type underneath. Most Australian domestic tap connections are DN15 (15 mm) with 1/2 inch BSP threads, but older homes may have non-standard arrangements.

💡 Choose a tap with a suitable WELS star rating to reduce water use without sacrificing performance.

Step 2: Isolate the water supply

2️⃣ Turn off water safely

Locate the isolation valves under the sink or basin. Turn off both hot and cold mini stops by rotating them clockwise.

If there are no local isolation valves, shut off the water at the property main. Then open the existing tap to drain pressure and residual water. Keep a bucket and towels under the work area.

If replacing a kitchen mixer, also check whether nearby appliances share the same cabinet space and need protection from spills.

Step 3: Inspect the existing pipework and valves

3️⃣ Check condition before removal

Before undoing anything, inspect:

If you see green corrosion on copper, rusted threads, swollen cabinetry or valves that do not fully isolate, the job may expand beyond a simple tap swap.

💡 If the mini stop valves are old, stiff or dripping from the spindle, replacing them at the same time is often worthwhile — but that work should be done by a licensed plumber.

Step 4: Disconnect the old tap

4️⃣ Undo the water connections

Place a bucket underneath. Using an adjustable spanner or multigrips, disconnect the hot and cold flexible connectors from the isolation valves.

For older taps with rigid copper tails, use care not to twist or kink pipework. Some installations use threaded tails with tube nuts; others use flexible braided hoses.

Allow remaining water to drain into the bucket.

Step 5: Remove the old mounting hardware

5️⃣ Release the tap from the sink or basin

From underneath the sink or vanity top, locate the retaining nut, horseshoe clamp, threaded shank or backnut holding the tap in place.

Use a basin spanner or tube spanner to loosen it. In tight spaces, this is usually the slowest part of the job. Once the retaining hardware is off, lift the old tap out from above.

If the base is stuck due to old silicone or grime, gently cut around it with a utility knife and lift carefully to avoid damaging ceramic or stainless steel surfaces.

Step 6: Clean and prepare the mounting surface

6️⃣ Create a clean sealing surface

Remove old silicone, putty, scale and debris from around the tap hole. Wipe the area clean and dry.

Check the mounting hole size against the new tap manufacturer’s requirements. Most mixer taps suit a standard basin or sink hole, but always verify the minimum and maximum hole diameter.

A clean, flat surface helps the rubber gasket seal properly and prevents the tap from rocking after installation.

Step 7: Assemble the new tap as per manufacturer instructions

7️⃣ Pre-fit components

Unpack the new tap and identify:

Many mixer taps require the flexible hoses to be threaded into the tap body before the tap is mounted. Tighten to the manufacturer’s instructions only — do not overtighten.

Check which hose is hot and which is cold. In Australia, hot is typically on the left and cold on the right when facing the tap.

Step 8: Install the new tap into position

8️⃣ Fit the tap to the basin, sink or bench

Feed the tap tails or braided hoses through the mounting hole from above. Make sure the base gasket is correctly seated.

From underneath, fit the retaining plate and backnut. Align the tap so the spout is centred and straight, then tighten the mounting hardware evenly.

Do not overtighten. The tap should be firm with no movement, but excessive force can crack basins, distort stainless sinks or damage the fixing kit.

For some sink installations, a stabilising plate may be supplied for thin stainless steel bowls. Use it if recommended.

Step 9: Connect the water supply lines

9️⃣ Reconnect hot and cold services

Attach the flexible connectors to the isolation valves. Usually these are DN15 (15 mm) / 1/2 inch BSP connections.

Start threads by hand to avoid cross-threading, then tighten with a spanner to the tap manufacturer’s guidance. Do not use thread tape on braided hose cone seals unless specifically directed by the manufacturer, because many flexi hoses seal on a washer or cone, not the thread.

Ensure:

Step 10: Turn the water back on gradually

🔟 Re-pressurise the system carefully

Leave the tap in the open position, preferably in the middle for a mixer. Slowly open the cold isolation valve, then the hot isolation valve.

This helps purge air and reduces sudden pressure shock. Water may sputter briefly as air leaves the lines.

Once water flows smoothly, close the tap and inspect all joints underneath with a torch and dry tissue or paper towel.

Step 11: Test for leaks, operation and temperature

1️⃣1️⃣ Check performance thoroughly

Run both hot and cold water and inspect:

If it is a mixer, confirm temperature blends correctly and that hot is on the left side. If fitted to a bathroom basin, confirm delivery temperature is safe and consistent where tempering is required in the broader plumbing system.

Let the tap run for 1 to 2 minutes to flush debris from new hoses and the aerator.

Step 12: Final fit-off and clean-up

1️⃣2️⃣ Finish the installation neatly

If the manufacturer calls for silicone around the base, apply a small neat bead of neutral cure sanitary silicone. Many modern taps rely on a gasket and do not require extra sealant, so follow product instructions.

Wipe down all surfaces, remove packaging and store the installation booklet and warranty details. Recheck for leaks after 15 to 30 minutes, and again after the first day of use.

Common Mistakes to Avoid

Pro Tips

💡 Choose WaterMark-certified tapware from reputable brands commonly supported in Australia, such as Caroma, Methven, Dorf, Phoenix, Oliveri or Clark.

💡 For kitchen sinks with thin stainless steel, use the supplied stabilising plate or spacer to reduce movement and improve long-term rigidity.

💡 If water pressure is very high, a new tap may become noisy or wear faster. A licensed plumber can check compliance with AS/NZS 3500 and whether pressure limiting is needed.

💡 Compare WELS star ratings before buying. A higher star rating can reduce water consumption, especially in bathrooms and ensuites used daily.

💡 Keep the aerator clean. After installation, debris from older pipework can lodge in the aerator and make a new tap seem faulty when it only needs flushing.

Recommended Tools

🔧 Recommended Tools

🔒 Licensing

Plumbing work in Australia must be performed by a licensed plumber. This guide explains the process and helps you select the right tools and materials. Licensing requirements vary by state, including NSW Fair Trading, VIC VBA, QLD QBCC and WA Building Commission. If the job involves altering pipework, replacing isolation valves, wall-mounted tapware, concealed plumbing, waterproofing interfaces, or any rectification of leaks inside walls or cabinets, engage a licensed plumber.