Water efficiency is rising up the agenda across both commercial and domestic buildings, but for many projects the conversation still tends to centre on taps, aerators and low-flow fixtures. These are really important measures, but there’s a bigger opportunity sitting in plain sight – upgrading legacy flushing systems. These are often overlooked but can deliver immediate and measurable savings without the need for major refurbishment or disruption.
With all the rain we get, it’s easy to assume the UK has no shortage of water. But although supply seems plentiful, water is finite. Not all rainfall is captured or stored, we’re seeing hotter summers and drier springs, and water-intensive technologies such as AI and data centres are putting an additional strain on supply.
Government white paper ‘A New Vision for Water’ sets out a strategy to improve water efficiency, reduce bills, safeguard future supplies and protect the environment. The Environment Act has set a target to reduce per capita water consumption by 20% by 2038, with further reductions beyond that. For building owner/operators, that means water efficiency is now an expectation.
THE HIDDEN PROBLEM
Smart meter data from Thames Water shows around 25% of water supplied to non-domestic buildings is classed as ‘continuous flow’ – a constant stream often caused by leaks or poorly managed systems. In many cases, the issue isn’t dramatic or obvious, just a slow, steady and unnoticed loss. Leaking cisterns are vulnerable to scale and impurities, which can quickly accumulate and compromise the watertight seals of the flushing system. Toilet leaks can be easily missed – they might be small, but a single leaking toilet can waste up to 400 litres of water a day.
Uncontrolled urinal flushing is another major source of waste. Urinals that operate on timed flush cycles can activate up to three times per hour, regardless of whether the facilities are used. This may once have been necessary for hygiene, but it can result in hundreds of thousands of litres of potable water being flushed away every year. Analysis from Thames Water shows that installing urinal controls can reduce water consumption by an average of 792 litres per day, with even higher savings in high-use environments such as schools.
SIMPLE UPGRADES
The good news is that, in many cases, relatively straightforward upgrades can deliver substantial savings. You can bypass cistern problems such as leaks and ongoing maintenance by installing direct flushing systems. These connect directly to the mains water supply and use dynamic water pressure to deliver an efficient single flush, reducing water use compared to traditional systems that may require multiple flushes.
Cistermiser’s Easyflush Direct, for instance, uses sensors to automatically flush after use. Compared to a leaky loo, it can save 146,000 litres of water per year, saving almost £600 per toilet. For urinals, direct flushing and control systems that link flushing to occupancy can make an immediate impact. Rather than flushing continuously, water is only used when the facilities are actually in use. Systems such as Cistermiser’s Direct Flush, for example, use PIR sensors to detect usage and only flush when needed. Using as little as 0.5 litres per flush, these systems can reduce annual water use significantly, with savings of up to 182,000 litres per urinal per year.
Where existing cisterns remain in place, infrared or hydraulic control valves can be retrofitted to manage refill cycles and prevent unnecessary flushing. For example, motion-activated valves only allow cisterns to refill when the washroom is in use, while hydraulic valves use pressure changes from taps or toilets to trigger refilling. These approaches can reduce water consumption by over 80% compared with uncontrolled systems.
In a market where sustainability targets are becoming more demanding, being able to offer practical, cost-effective water-saving solutions adds real value. While small changes like aerators can help, the biggest gains often come from addressing the systems that are quietly wasting water every day. By focusing on these areas, installers can help clients reduce consumption, lower costs and futureproof their buildings without the need for major overhaul. www.cistermiser.co.uk