Water Saving Toilets

A water-saving toilet reduces the volume used per flush while still needing enough force and flow to clear the pan and carry waste through the drain. Choosing a proven design and installing it correctly is more important than selecting the lowest flush volume on the label.

Before you worry

An efficient toilet should not require repeated flushing. If a low-volume toilet regularly needs two or three flushes, the mechanism, water level, pan design or drainage conditions should be checked.

How to recognise the problem

• High household water use from older toilets.
• Large old cisterns using the same volume for every flush.
• Interest in dual-flush or reduced-volume upgrades.
• Repeated running faults increasing water loss.
• Renovation creating an opportunity to improve efficiency.

Common causes

• Older high-volume toilet designs.
• Leaking flush seals or inlet valves.
• Incorrect dual-flush adjustment.
• Poorly performing low-quality replacement mechanisms.
• Repeated flushing caused by weak performance.

What you can safely check yourself

• Check the litre-per-flush rating of proposed models.
• Choose products with locally available parts.
• Confirm outlet compatibility before purchase.
• Repair running toilets before measuring savings.
• Consider household needs and accessibility.

What you should never do

• Do not reduce cistern water below the manufacturer setting.
• Do not choose a toilet solely by the smallest advertised volume.
• Do not ignore drain condition when changing flush characteristics.
• Do not fit incompatible conversion mechanisms.

When to call a plumber

Consult a plumber when replacing the pan, converting an old cistern, altering the outlet or assessing why an efficient toilet is performing poorly.

How professionals solve it

A plumber confirms model suitability, outlet position, water connection and expected flush performance. The toilet or mechanism is installed and adjusted to specification, then tested with normal and full-flush cycles to ensure water savings do not create repeated blockages.

How to prevent it happening again

• Repair running toilets quickly.
• Keep valves and seals serviceable.
• Use reduced and full flush settings appropriately.
• Avoid flushing items the toilet was not designed to carry.
• Investigate weak flushing rather than increasing water level blindly.

Frequently asked questions