Hard water is a problem in many homes in the UK. Sophie Mellor shares her top tips on handling hard water issues and preventing homes from being affected in the future.

Over 65% of homes in the UK have hard water. As it is a problem in many properties, it is crucial to know how to identify a house with hard water and understand how to help customers living in properties affected by it.


What is hard water?


The water that is fed into UK homes originates from rain water and goes through a thorough harvesting process to ensure that all impurities are removed and it is clean enough for domestic use.


However, as rainwater is a good solvent, it can easily pick up these impurities, and some remain through the purification process. Water that is classed as ‘hard’ has a high mineral content, which is due to dissolved magnesium and calcium compounds. These become dissolved in the water when it comes into contact with chalky rocks such as dolomites and limestone. Rainwater that does not percolate through chalky rocks has low or very low mineral content and is described as ‘soft’. 


Determining whether a house has hard water


One of the most common ways to check whether a house has hard water is by mixing water and soap. When soap is mixed with soft water, it lathers up easily to form a stable foam. However, it does not make or maintain a foam nearly as well with hard water.


Hard water can also leave behind a deposit within the kettle, known as a build up of limescale. This usually will appear as an off-white crust at the bottom of the kettle or attached to the kettle element.


Living with hard water


Although hard water isn’t harmful to health, it can be a nuisance as it impacts on day-to-day tasks such as showering, cleaning the dishes and doing the laundry.


Over time, laundry and crockery can also start to look dull and unclean as popular detergents are often unable to work effectively as a result of hard water.


The biggest issues occur when hard water is heated above 55°C, as this causes the minerals to come out of solution and form a scale deposit. Your customers may have already identified limescale build up on their taps, which can be difficult to clean. However, the largest problems happen behind the scenes.


Dealing with a limescale build up


Limescale build up in pipes, boilers and appliances can prevent them from operating efficiently, which can lead to higher energy bills and increased repairs. 



  • Pipes: When limescale builds up in pipes, it reduces pipe diameter which means that pumps have to work just a little bit harder, increasing energy use and shortening component life



  • Boiler: Limescale build up in a boiler occurs on the heat exchanger. Limescale deposits act as insulation, reducing the efficiency of heat transfer surfaces, so limescale deposits on the heat exchanger means the boiler has to fire more often to maintain water temperature. This can dramatically increase fuel bills



  • Appliances: The effect that limescale has on a small kettle is intensified on larger appliances such as washing machines and dishwashers. The build up can make them less energy efficient and lead to appliances breaking down more frequently.  



Removal methods


Treating hard water can be quite simple and, in comparison to the effects it can have on the household bills, is also cost effective. There are many different water softening methods that can be employed to remove limescale build up in your customers’ homes to prevent any further damage.


For appliances such kettles, dishwashers and washing machines, your customers can remove the limescale themselves using lemon juice or vinegar. For stubborn deposits, they should use proprietary products bought in the supermarket. As limescale is quite stubborn, affected areas may need to be soaked in the solution.


Pipes and boilers require an alternative, more effective method in order to remove the limescale. A solution containing chemicals that react with calcium and remove limestone should be flushed through them.


Long term solutions


Once any build up of limescale has been removed, you should recommend that customers adopt a longer term solution to prevent any future issues.


A common method is water softening, a chemical process in which scale-forming calcium and magnesium are swapped for sodium so that even on heating, scale deposits cannot occur.


A liquid inhibitor solution is also a good way to maintain clean central heating systems and provide protection from corrosion and limescale, while on the secondary hot water side, installing an electrolytic scale inhibitor can offer life-long protection from limescale build up.


Sophie Mellor is content writer for water treatment specialist Sentinel.


Picture courtesy of Shutterstock/Nomad Soul