Quick Answer
Screw an inexpensive pressure gauge onto any outside tap and turn it on fully. Normal household pressure is 350–500 kPa. Above that, you risk damaging appliances; below 200 kPa, something is restricting your supply.
Most Sydney homeowners only think about water pressure when something is clearly wrong — a weak shower, a banging pipe, or a suddenly huge water bill. But pressure issues are one of the easiest things to diagnose yourself before booking a callout.
The quick test
Pick up a screw-on pressure gauge from any hardware store. Screw it onto an outside tap, turn the tap fully on, and read the dial. Normal household pressure sits between 350 and 500 kPa. Anything above 500 kPa is too high; below 200 kPa is too low.
If pressure is too high
High pressure shortens the life of every appliance in your home — dishwashers, washing machines, and especially hot water units. Sydney Water mains can deliver pressure well above what household plumbing is designed for, which is why a pressure-limiting valve (PLV) is required by the plumbing code on all homes built after 2008.
If yours is older, or your PLV has failed (they typically last about a decade), water hammer and leaks become inevitable. Replacing a failed PLV is a straightforward job for a licensed plumber.
If pressure is too low
Low pressure across the whole house usually means a partially closed main stop tap, a clogged PLV, or a corroded galvanised supply line in older homes.
Low pressure at just one outlet is almost always a blocked aerator or cartridge — a 10-minute DIY fix.
The hidden warning sign
If your water meter is ticking over while every tap and appliance in the house is off, you have a leak somewhere — and pressure issues often go hand in hand with it. Do not ignore it; underground leaks can cause significant damage by the time they surface.
Not sure what your reading means? Send us a photo of the gauge and we will tell you straight up whether it is a callout job or a DIY fix.
Pressure Problems? We Can Help
Mr. Clog diagnoses and fixes water pressure issues across Sydney — from PLV replacement to leak detection.