It can be frustrating when water flows slowly from your tap. In many cases, the cause isn’t serious. Low tap pressure is often caused by mineral buildup, partially closed valves, or supply issues rather than major pipe failure.
While weak flow can be inconvenient, the issue is usually identifiable.
The Most Common Reasons This Happens
1. Clogged Aerator
Most taps have a small mesh screen (aerator) at the tip. Over time, mineral deposits can block it, reducing water flow.
Unscrewing and cleaning the aerator often restores pressure immediately.
2. Partially Closed Shut-Off Valve
Under-sink shut-off valves may be slightly closed after maintenance. Even a small restriction can reduce pressure noticeably.
Checking both hot and cold supply valves is a simple step.
3. Mineral Buildup Inside the Tap
Hard water can build up inside internal components, restricting flow.
If your tap is also dripping, see Why Is My Tap Dripping?
4. Supply Line Issue
If both hot and cold water have low pressure, the issue may relate to the home’s water supply or pressure regulator.
If other fixtures are affected, it may not be isolated to one tap.
5. Plumbing Leak
A hidden leak in the system can reduce pressure while increasing water usage.
If you’ve noticed unusual toilet behaviour, see Why Is My Toilet Running Constantly?
Is This Normal?
Minor pressure variation can happen occasionally.
It may be minor if:
• Only one tap is affected
• The aerator hasn’t been cleaned recently
• The issue developed gradually
It may not be normal if:
• Multiple fixtures have low pressure
• Pressure drops suddenly
• Water flow fluctuates dramatically
When Should You Worry?
You should investigate further if:
• Pressure drops throughout the home
• You hear banging pipes
• There are signs of leaks
• Water appears discoloured
Persistent low pressure may require professional inspection.
What You Can Do
If your tap water pressure is low, you can:
• Clean the aerator
• Check shut-off valves
• Inspect visible supply lines
• Monitor other fixtures
• Contact your water supplier if necessary
If pressure doesn’t improve, a plumber can inspect internal piping.
In most situations, low tap pressure is caused by mineral buildup or valve adjustments rather than major plumbing failure. Cleaning and simple checks often restore normal flow. If the issue persists, professional assessment may be required.