Much of London and Essex has hard water, which is high in dissolved calcium and magnesium. It’s safe to drink, but when it’s heated or left to evaporate it leaves limescale, a hard, chalky deposit that builds up wherever water flows. Over time, it causes more plumbing problems than most people realise.
Blocked shower heads
Shower heads are usually the first thing to suffer. Scale builds up inside the nozzles, so jets spray sideways, weaken or stop altogether, like the large rain head above. Flexible rubber nozzles can be cleared by rubbing them, but heavily scaled heads need descaling or replacing.
Shower valves and cartridges
Limescale gets inside thermostatic valves and cartridges, making controls stiff, temperatures unstable and showers drip after they’re turned off. See our guides to shower mixer valve replacement and the faulty shower cartridge case study.
Appliances and water treatment units
Appliances that heat water, such as steam ovens, coffee machines, kettles, boilers and washing machines, are especially vulnerable. Many steam ovens and commercial appliances are fitted with a calcium treatment unit like the one above, which treats the water before it reaches the appliance. These units have a limited life and need replacing on schedule, or scale gets through and damages the appliance.
Toilets, cisterns and macerators
Scale builds up on fill valves, flush valves and float arms, causing toilets that run constantly or flush weakly. See our guide to running toilets and weak flushes. In macerators and waste pumps, scale on switches and membranes stops the unit switching on and off properly. See our macerator and pump guide.
Boilers and heating
Scale in a combi boiler’s hot water heat exchanger reduces hot water flow and efficiency, and can cause noise and breakdowns. A scale reducer on the cold supply to the boiler helps protect it.
What you can do
- Descale shower heads, taps and aerators regularly with a limescale remover or vinegar solution
- Replace water treatment cartridges and units on the manufacturer’s schedule
- Fit a scale reducer on the supply to a combi boiler or hot water cylinder
- Consider a water softener for the whole house in very hard-water areas. Keep a separate unsoftened drinking water tap
- Get dripping valves and running cisterns fixed early, because scale makes them worse over time
Book a plumber
Our plumbing team descales, repairs and replaces shower heads, valves, cartridges, cisterns and water treatment units for homeowners, landlords and businesses. See our plumbing and heating service.
We cover London and Essex, with our own engineers working every day across Chigwell, Loughton, Buckhurst Hill, Woodford, Ilford, Romford, Brentwood and Epping. Call 020 8227 0035 or request a quote.