My water supply

Hard water in the home

In the home, hard water can lead to the furring and scaling of heating systems, kettles and household appliances such as washing machines.

How much fur or scale build up usually depends on the hardness of the water, the type of system involved, the temperature to which the water is heated and how much water is used.

Hard water is perfectly safe and there's a lot of evidence that it can be good for our health. Calcium is essential for normal growth and health, and if you're in a hard water area, your drinking water can contribute towards your daily calcium intake. However if you want to reduce the amount of scale or furring, there are steps you can take.


Red kettleUsing hard water in kettles produces calcium carbonate scale or fur. In metal kettles this sticks to the side and in plastic kettles, which have smoother sides, it appears as a film on top of the water.

This scale does not increase the time it takes to boil the water or the amount of fuel you need. However, we do recommend you remove it regularly.

Only boil the water you need, not only does this help with water efficiency, it will help prevent kettle limescale by not boiling the same water over and over again. 
You can de-scale your kettle by half filling it with water and adding two tablespoons of white vinegar. Leave it for four hours, then empty the kettle and remove the loosened scale. Rinse and repeat as necessary. As an alternative you can buy a scale remover, and follow the instructions on the packet.


Many dishwashers have a built-in water softener to provide water for rinsing dishes. These remove salts which could otherwise be left as scale on drained washing up.

Make sure your dishwasher is regularly topped up with dishwasher salt.

Baths, showers, sinks and toilets

Thin films of limescale can form on the smooth surfaces of baths, basins and toilets, providing a surface on which dirt and grime can stick to. 

Clean regularly using a liquid cleaner. Abrasive materials may scratch the surface. If the limescale persists in your toilet you may want to regularly clean the pan with an acid-type sanitiser available from DIY stores and supermarkets.

Do not mix cleaners and always ensure you read instructions carefully.

Direct heating systems

These are the traditional method for heating water. Water travels from a tank in the roof, to a boiler, where it is heated. The water then rises to a cylinder in the airing cupboard, where it stays until you use it.

To avoid scale simply avoid overheating the water. A maximum temperature of 60°C (140°F) is recommended. 

You can reduce scaling in heating systems by using a chemical scale inhibitor, but we suggest you take advice from an approved plumber before using these.
Indirect heating systems

These do not tend to produce scale. This is because the same water goes round the system so only a tiny amount of scale is produced.

Immersion heaters

Immersion heaters can be susceptible to too much scale building up on the heating element and stopping the water circulating properly.

Make sure the thermostat is working and correctly adjusted. For most homes 60°C is sufficient. If you regularly use an immersion heater it may be possible to prevent the build-up of scale by using elements with special metal sheaths.

In some cases you may also want to use a chemical scale inhibitor, but we suggest you take advice from an approved plumber before using these.

Water softeners

Installing a water softener is a matter of personal choice. We recommend that if you install a water softener you keep a mains water source for drinking purposes.

This is because some water softeners increase sodium levels, which may have negative impacts to health.

Magnetic and electrical scale inhibitors

There are a number of devices available which claim to stop scale and fur from forming.

While many have been approved by the Water Regulations Advisory Scheme (WRAS) as devices that will be safe to use, this does not guarantee their effectiveness.

Your own plumbing design and other local factors may influence how well the equipment works. It is wise to get a guarantee, with a money-back clause, from the manufacturer in case you are not satisfied with the results.