A water bill that doubles with nothing else changing is not a billing error often enough to be worth assuming. Usually it means water is leaving the system somewhere, continuously, and has been since the last read.
The good news is you can narrow it down yourself in about ten minutes, and the answer you get is genuinely useful to whoever you call next.
The meter test
This is the single most useful thing you can do before ringing a plumber.
- Turn off every tap and every appliance that uses water. Include the washing machine, the dishwasher, the irrigation, the pool top-up and the ice maker in the fridge. Nothing in the house should be drawing water.
- Go to the water meter at the front boundary and note exactly where the dial and the digits sit. Photograph it — it is easier than remembering.
- Wait fifteen minutes. Do not use any water, including flushing a toilet.
- Look again.
If it has moved, water is escaping between the meter and the house. That is a continuous loss, it is on your side of the meter, and it is costing you every hour of every day.
If it has not moved, the loss is intermittent — something that runs sometimes rather than constantly. A toilet that occasionally refills, a solenoid on an irrigation controller, a hot water system relief valve weeping when the tank heats. These are harder to catch and still worth chasing.
Either answer halves the search. Tell us which one you got when you call.
What to check with your own eyes
Before anything technical, there are a few places water shows up:
- A warm patch on a tiled or concrete floor. That is a hot water line under the slab, and it is the classic one people walk across for months.
- The sound of running water with every tap off. Stand in a quiet house at night. A supply leak inside a wall is often audible before it is visible.
- Paint bubbling, skirting lifting, or a musty smell in one room. Water moves to the lowest point it can find, which is frequently not where the leak is.
- A patch of lawn that stays green through a dry fortnight. Or, conversely, a soft patch of ground near the boundary.
- The toilet bowl with a permanent ripple in it. A toilet that runs on quietly is the biggest invisible water waster in most houses — far more than a dripping tap, because it never stops and nobody hears it.
The cheap causes first
It is worth ruling out the inexpensive explanations before assuming the worst, because they are also the most common:
- A running toilet. Usually a worn outlet washer or a failed inlet valve, and cistern parts are largely universal, so it is a quick fix. See toilet repairs.
- A dripping tap. One tap can waste up to 24,000 litres a year. Two or three around the house adds up to a noticeable number on a quarterly bill. See tap repairs.
- Irrigation. A cracked poly line or a solenoid that is not closing properly will water the garden at three in the morning and never be seen.
If the meter test said "continuous" and all the taps and toilets in the house are sound, the leak is in the pipework, and that is when it is worth getting it located properly.
Why locating it matters more than finding it
Knowing there is a leak is not the same as knowing where it is, and the difference is what it costs to fix.
The alternative to locating a leak is opening things up until you find it — tiles, plasterboard, slab. We would rather narrow it down first, repair it, and leave you with a bill that goes back to looking like it used to. Catching it early also matters for a reason that has nothing to do with water: a slow leak inside a wall is a building problem long before anyone notices the bill.
What it costs
Leak detection is quoted after an inspection. Until we know where the water is going, a price is a guess, and we would rather give you a number we will stand behind.
What we can say is that the visit is worth more to you if you have done the meter test first, so do that before you call.
Call us and describe it
Tell us what the meter did, whether you have a warm patch anywhere, and when the bill changed. That is usually enough for us to know what we are walking into.
More on leak detection. If water is actively running and you cannot stop it, turn the water off at the meter and treat it as an emergency.
More on Leak detection, including what we charge.