SCHOOL LEAK DETECTION
Washroom block and urinal flush control leaks
Separate leaking fittings from hidden pipework faults in busy washrooms.
An uncontrolled urinal cistern flushes on a timer regardless of use, so a school washroom can run all night, every weekend and through every holiday.
WHAT TO LOOK FOR
Leak symptoms and common faults
- Urinal cistern flushing on a timer with no occupancy control
- Audible flushing in an empty building at any hour
- Failed hydraulic or infrared flush control stuck open
- Continuous flow into the cistern rather than periodic filling
- WC cistern float valve passing to the overflow
- A permanent trickle at an external overflow pipe
- Push-button tap or sensor tap failing to close
- A basin tap that never quite stops
- Concealed pipework in a duct behind a washroom panel
- Damp at low level in a corridor adjoining the washroom
Why urinals are the first thing to check on a school water bill
An uncontrolled urinal cistern fills and dumps on a fixed cycle. It does not know whether the school is open. Left uncontrolled, a single cistern flushes through the night, the weekend and the whole of August, and it does it silently enough that nobody in a locked building hears it.
Across a school with several washroom blocks this is routinely the single largest avoidable item on the water account, and it is the cheapest to fix.
What a controlled urinal actually looks like
Control means the cistern only fills when the washroom has been used. The common approaches are a hydraulic valve that responds to pressure changes elsewhere in the building, an infrared sensor on the cistern inlet, or a solenoid on a time switch tied to the school day.
Waterless urinals remove the flushing question entirely but introduce a maintenance regime that schools have to actually follow. They work where somebody owns the cartridge replacement schedule and fail where nobody does.
Checking a washroom block properly
- Read the meter after the site closes and again before it opens, which gives the overnight volume for the whole school
- Isolate the washroom blocks at their branch valves and repeat, which tells you how much of that is washrooms
- Inspect each cistern for continuous inflow, each overflow for a trickle, and each tap for failure to close
- Where the loss persists with every fitting eliminated, survey the concealed pipework in ducts and behind panels
Working out what the fault is costing before you fix it
The arithmetic is worth doing because it is what gets the repair approved. Measure the loss in litres per minute, multiply out to a year, convert to cubic metres, and apply your own volumetric rate from the water bill. Remember to add the wastewater charge, which for most schools is billed on the same volume.
Do not use a figure from a website, including this one. Use your own rate off your own bill, because non-household water charges vary by wholesaler and retailer and the whole point of the calculation is that it survives scrutiny from your finance team.
Arrange a school leak detection survey
School leak survey questions
How do I know if our urinals are controlled?
Stand in the washroom in an empty building and wait. A controlled cistern will not fill unless the washroom has been used. If it fills anyway, on a cycle, it is uncontrolled, and that is a fixable fault rather than normal behaviour.
Are waterless urinals a good idea for a school?
They work when someone owns the maintenance regime and follows it. In a school where the cleaning contract changes and nobody is clearly responsible for cartridge replacement, they tend to fail and get worked around. Controlled flushing is often the more durable answer.
We fixed the urinals and the bill is still high. What now?
Then the loss is elsewhere and you now know that, which is progress. The next step is an overnight meter reading with the washroom branch isolated, so you can prove the remaining loss is on another part of the site.
Sources for this page
- Source: The National Archives, The Water Supply (Water Fittings) Regulations 1999 (opens in a new tab) ().
Last reviewed . How this site sources and dates its figures.