Low Water Pressure — Causes and How to Fix

Blocked tap aerator

The mesh aerator on a tap collects limescale and debris over time, reducing flow to that tap. Unscrew the aerator from the tap spout, clean or replace it.

Partially closed isolation valve

Isolation valves under sinks and behind toilets are sometimes left partially closed after maintenance. A quarter-turn to fully open restores flow.

Failing pressure-reducing valve (PRV)

Properties with high mains pressure have a PRV fitted. When it fails, it can restrict pressure too much throughout the whole property.

Mains supply issue

Check with neighbours and the water provider (Anglian Water for Norwich). Supply issues or work on the main affect the whole street.

Internal leak

A significant internal leak reduces available pressure. Check water usage on the meter with all taps off.

Practical checks and next steps

Tap aerators clog with limescale and are easy to unscrew and clean. Isolation valves may be partially closed after previous work. But if pressure is low throughout the house, a pressure-reducing valve or supply issue needs professional assessment.

• Is it one tap or all taps? Isolate whether it's a single point or whole property issue.
• Unscrew and clean the aerator on the affected tap.
• Check the isolation valve under the sink is fully open.
• Check with a neighbour — is their pressure also low?
• Call Anglian Water (0800 169 3630) to check for supply issues.
• If whole-property and no supply issue reported, call a plumber.