High Water Pressure: Why It’s Secretly Damaging Your Pipes

Photo by David McElwee on Pexels

Strong water pressure feels fantastic in the shower. Taps fill the sink fast. The garden hose actually reaches the back fence. So when someone tells you your water pressure is too high, your first reaction is probably: what's the problem?

The problem is happening inside your walls, under your floors and behind every fitting in your home – silently, every hour of every day. Excessively high water pressure is one of the most common and most overlooked causes of plumbing failures on the Gold Coast. It stresses pipes, wears out washers faster, damages appliances and dramatically shortens the life of your entire plumbing system.

This guide explains what counts as "too high," the damage it causes, how to check your pressure, and the straightforward fix that protects everything downstream.

What Is Normal Water Pressure?

Water pressure is measured in kilopascals (kPa). In Australia, the standard range for residential properties is:

• 200–500 kPa – the acceptable operating range under AS/NZS 3500
• 500 kPa – the maximum recommended pressure at any fixture
• Above 500 kPa – considered excessive and likely to cause damage over time

For context, most people find shower and tap pressure comfortable between 300–400 kPa. Anything above 500 kPa is putting unnecessary stress on your system.

Gold Coast water mains pressure varies by suburb and elevation. Properties at the bottom of hills or close to pump stations often receive significantly higher pressure than those at the top. It's not uncommon for Gold Coast homes to receive mains pressure of 600–800 kPa without a pressure limiting valve installed.

Signs Your Water Pressure Is Too High

High pressure doesn't always announce itself obviously. Watch for these warning signs:

• Banging pipes (water hammer) – a loud thud or bang when taps are turned off quickly. This is the momentum of fast-moving water slamming to a stop inside the pipe. Over time, water hammer loosens joints and damages fittings.
• Dripping taps that keep returning – you replace the washer, it's fine for a few weeks, then it starts dripping again. High pressure accelerates washer wear, creating a cycle of repeat repairs.
• Leaking toilet cistern valves – the inlet valve in your cistern is designed for a certain pressure range. Excessive pressure causes it to leak past the seal, resulting in a constantly running toilet or phantom filling.
• Appliance failures – dishwashers, washing machines and ice makers have internal hoses and solenoid valves rated for standard pressure. Consistently high pressure shortens their lifespan and can cause hose bursts.
• Hot water system relief valve discharging frequently – the temperature and pressure relief (TPR) valve on your hot water system opens to release excess pressure. If it's dripping regularly, incoming pressure may be the cause (not just temperature expansion).
• Burst flexi hoses – braided flexible connectors under sinks and behind toilets are a leading cause of internal flooding in Australian homes. High pressure accelerates the fatigue that leads to sudden bursts – often when you're not home.
• Short fixture lifespan – if mixer taps, shower cartridges and cistern components seem to wear out faster than they should, pressure is a likely contributing factor.

Why Is My Water Pressure So High?

Mains Supply Pressure

The most common cause. Gold Coast City Council's water network delivers pressure based on the infrastructure in your area – reservoir elevation, pump station proximity and pipe sizing. If your home sits in a high-pressure zone, every fixture in the house receives that pressure unless a limiting device is installed.

No Pressure Limiting Valve (PLV) Installed

Many older Gold Coast homes were built without a pressure limiting valve. Even some newer homes have PLVs that were set too high or have failed over time. Without a working PLV, whatever pressure the mains delivers goes straight through to your internal plumbing.

Thermal Expansion

When your hot water system heats water, the water expands. In a closed system (no expansion valve or no relief path), this expansion temporarily spikes pressure throughout the hot water side of your plumbing. This is separate from mains pressure but compounds the problem.

Elevation Changes

If your property is at a lower elevation than the local water supply reservoir or tank, gravity adds to the pressure. A 10-metre elevation difference adds roughly 100 kPa of pressure.

How to Check Your Water Pressure

You can test your home's water pressure with an inexpensive pressure gauge (available from Bunnings for under $30):

1. Screw the gauge onto an outdoor tap or laundry tap
2. Make sure no other taps or appliances are running
3. Turn the tap on fully and read the gauge

If the reading is above 500 kPa, your pressure is excessive and action is recommended. If it's above 600 kPa, it's urgent – the risk of a burst flexi hose or fitting failure increases significantly.

For a more thorough assessment, a licensed Gold Coast plumber can test pressure at multiple points and check whether your existing PLV (if you have one) is functioning correctly.

If you're also seeing unexplained spikes in your water bill, high pressure may be driving small leaks you haven't found yet. Our guide on how to test your home water pressure covers the process in more detail.

The Fix: Pressure Limiting Valves

The solution to high water pressure is a pressure limiting valve (PLV), also called a pressure reducing valve (PRV). It's a compact brass device installed on your main water supply line – typically at or near the water meter – that mechanically reduces incoming pressure to a safe, consistent level.

How a PLV Works

Inside the valve, a spring-loaded diaphragm balances against the incoming water pressure. When pressure exceeds the set point (usually adjusted to 350–500 kPa), the diaphragm partially closes the valve, restricting flow enough to maintain the target pressure downstream. When demand increases (multiple taps open), the valve opens wider to maintain consistent pressure.

The result: every tap, shower, appliance and fitting in your home operates within its designed pressure range, regardless of what the mains is delivering.

Do I Already Have One?

Check near your water meter (front boundary) or where the main supply pipe enters your home. A PLV looks like a bell-shaped or cylindrical brass fitting with an adjustment screw on top. If you have one, it may still need servicing – PLVs can fail or drift out of adjustment after 8–12 years.

For a detailed breakdown of PLV types, installation and maintenance, see our companion guide: Pressure Limiting Valves: What They Are & Why You Need One.

What Happens If You Ignore High Pressure?

The consequences compound over time:

• Premature pipe joint failures – especially at soldered copper joints, compression fittings and push-fit connections
• Flexi hose bursts – the single biggest cause of home insurance water damage claims in Australia. A burst flexi hose can release hundreds of litres per hour
• Appliance warranty issues – manufacturers specify maximum operating pressure. Damage from excessive pressure may void your warranty
• Higher water bills – high pressure means higher flow rate at every tap. Even brief tap usage wastes more water than necessary
• Recurring repair costs – replacing washers, cartridges and valves every year adds up quickly when the root cause isn't addressed

Installing a PLV once addresses all of these issues permanently.

Prevention: Protecting Your Gold Coast Home

Beyond installing a PLV, these measures protect your plumbing from pressure-related damage:

• Replace braided flexi hoses every 8–10 years as a precaution – regardless of visible condition. Mark the installation date on each hose with a permanent marker
• Install water hammer arrestors at washing machine and dishwasher connections if you hear banging after valve closure
• Add an expansion control valve if your hot water system has a non-return valve on the cold inlet – this prevents thermal expansion pressure spikes
• Schedule a plumbing health check every 2–3 years – a licensed plumber can test pressure, inspect flexi hoses, check the PLV and identify developing issues before they cause damage
• Turn off washing machine taps when not in use – this removes constant pressure from the flexi hoses when you're away or overnight

Stop the Silent Damage

High water pressure is one of those problems that costs almost nothing to fix upfront but causes thousands in damage if left unchecked. A pressure limiting valve is a one-time installation that protects your entire plumbing system, your appliances and your peace of mind.

If you're seeing any of the warning signs – water hammer, recurring drips, frequent washer replacements or a hot water relief valve that won't stop – book a pressure check with a Gold Coast plumber. It takes less than an hour and gives you a clear picture of what your system is dealing with.

Frequently Asked Questions

What water pressure is too high for a house in Australia?
Anything above 500 kPa is considered excessive under Australian Standards (AS/NZS 3500). Most plumbers recommend keeping residential pressure between 350–500 kPa for optimal performance and longevity.

Can high water pressure burst pipes?
It can, though it more commonly causes gradual failure – weakening joints, wearing seals and fatiguing flexi hoses until they eventually give way. Sudden bursts are most likely in older braided flexi connectors under sustained high pressure.

How much does a pressure limiting valve cost to install on the Gold Coast?
A PLV installation is a relatively modest investment for the protection it provides. The valve itself is a standard plumbing component, and installation typically takes 1–2 hours. Your plumber can provide a fixed quote after assessing your meter location and pipe configuration.

My shower pressure is already weak – could I still have high pressure?
Yes. Weak shower flow is often caused by a restricted shower head, clogged aerator or partially closed isolation valve – not necessarily low mains pressure. You could have 700 kPa at the meter and poor flow at the shower due to a localised restriction. Testing at the meter or a laundry tap reveals your true supply pressure.

Does high pressure affect my hot water system?
Absolutely. Excessive pressure accelerates wear on inlet valves, causes the TPR valve to discharge more frequently, and can contribute to tank fatigue over time. A PLV protects your hot water system alongside everything else in the house.

Resources

• Standards Australia – AS/NZS 3500 Plumbing and Drainage
• Insurance Council of Australia – Flexi Hose Failure Prevention
• Master Plumbers' Association of Queensland (MPAQ)
• Gold Coast City Council – Water Supply and Pressure