Warning Signs You Need a Plumber

Low or Inconsistent Water Pressure

A sudden drop in water pressure — particularly affecting the whole house rather than just one tap — usually indicates a problem upstream. Common causes include a partially closed isolation valve, a failing pressure limiting valve, a significant leak on the supply line, or a problem with the water main. If pressure drops gradually over weeks, mineral buildup inside older pipes or a failing PRV are likely suspects.

If only one tap has low pressure, it's usually a blocked aerator or a failing cartridge in that tap — a simpler fix. But if it's house-wide, it's worth having a plumber investigate before the cause worsens.

Slow or Gurgling Drains

A slow drain that doesn't respond to a plunger or hot water is usually a partial blockage that will become a complete one. Multiple slow drains at the same time — particularly in different areas of the house — often indicate a blockage further down the sewer line rather than individual trap blockages. Gurgling sounds from drains or the toilet when water runs elsewhere are a sign that air is trapped somewhere in the drain system, which can indicate a vent blockage or a developing partial blockage.

• Single slow drain — likely a partial blockage in that drain or trap
• Multiple drains slow at once — possible sewer line blockage
• Gurgling toilet when shower runs — drain vent or sewer line issue
• Drain odours — partial blockage or vent problem

Discoloured Water

Brown or rust-coloured water coming from taps is usually a sign of corrosion inside older galvanised steel pipes, or a deteriorating hot water tank. It can also occur temporarily after a disturbance to the water main — in which case it clears on its own within a few minutes of running the tap. If it persists, or if the discolouration is only in the hot water, the hot water system is the likely source and may need replacement.

Cloudy water that clears when left to settle is usually dissolved air — harmless and common in cold weather. Cloudy water that doesn't clear may indicate contamination and warrants investigation.

Higher Than Usual Water Bills

An unexplained increase in your water bill is one of the most reliable indicators of a hidden leak. Even a small continuous drip — from a running toilet, a dripping tap, or a pinhole leak in a supply line — adds up significantly over a billing period. A continuously running toilet cistern can waste thousands of litres per month and often goes unnoticed because it's quiet.

To check a toilet for leaks, add a few drops of food colouring to the cistern. If colour appears in the bowl without flushing, the cistern is leaking into the pan through the flush valve or overflow — a common and easily repaired issue.

Banging or Hammering Pipes

A banging sound when taps are turned off quickly — often called water hammer — is caused by the momentum of water in the pipe suddenly stopping. It's more common in older homes and can gradually loosen pipe fittings if left unaddressed. A licensed plumber can install water hammer arrestors or adjust pressure to resolve it. Pipes that knock or rattle when water is running may indicate unsecured pipe runs that need to be clipped back.

Damp Patches, Mould, or Musty Smells

Unexplained damp patches on walls or ceilings, mould growth near pipes or fixtures, or a persistent musty smell in a room with plumbing are all signs of a possible concealed leak. These are worth investigating promptly — water damage inside walls and floors compounds quickly and the remediation becomes significantly more expensive the longer a leak continues.

• Damp or stained ceiling below a bathroom — pipe or fitting above is leaking
• Mould at base of toilet or vanity — slow leak at the base fitting
• Soft or spongy flooring near wet areas — long-term moisture ingress
• Musty smell without visible mould — leak inside wall cavity