What is Limescale?

17 June 2013

If you live in a hard water area then there’s every chance you are all too familiar with limescale. The very mention of the word may send an irritable shiver down your spine. Even the terms associated with limescale are pretty unpleasant – furring, descaling, scum. Limescale is a problem that we have been tackling head-on at Aquatec – the Pure Water People so we thought we’d answer the question – what is limescale?  

What is Limescale?

Limescale is the chalky off-white crust that lurks inside your kettle and boiler and stains your surfaces. But you probably already knew that. Scientifically speaking limescale is a deposit of calcium carbonate and a residue left behind by hard water.

And hard water? Well, hard water is water that contains a higher concentration of dissolved minerals like calcium and magnesium.  When the water evaporates, it leaves behind calcium carbonate deposits. These limescale deposits therefore build up on any surfaces that hard water is in contact with and can accumulate quickly. Unfortunately, limescale loves to stick to limescale and these deposits are tough to get rid of as well as being unsightly.

You will find limescale in many places, some that you can see and others where it is hidden from view. Limescale can be found inside your water pipes, on the heating elements of a boiler and on any surface where water has evaporated.

The two most common problem areas of the home are:


  • Toilet
  • Taps
  • Bathroom tiles
  • Sink
  • Shower
  • Pipes
  • Other surfaces


  • Kettle
  • Coffee machine
  • Washing machines
  • Dishwashers
  • Taps
  • Tiles
  • Pots and Pans
  • Other surfaces

Why is Limescale a problem?

Limescale causes problems across a number of areas from the minor and superficial to the major. There is on-going debate in the science community as to just how harmful limescale is to your health, if at all. We’ll leave that discussion for another time and instead focus on the practical issues surrounding limescale.

  • Limescale will often cover taps, sinks and hard surfaces with an ugly layer of off-white that is tough to remove. You don’t have to be Kim and Aggie to find this an issue.
  • Chalky-white flakes floating in your tea and coffee are bad news, but your poor kettle suffers most visibly from limescale deposits and will need to be replaced regularly.

It is the hidden damage that is the most worrying and potentially damaging for homeowners.

  • Hard water poses the biggest issue when heated or left to stand.  When hard water evaporates, the minerals left behind soon solidify becoming limescale. Build-ups can occur in domestic plumbing systems. As limescale deposits inside central heating pipes accumulate, they can restrict the flow of water or even causing a blockage.
  • Just like with your kettle, limescale is hardening around components in your washing machine and dishwasher. Not only does this make your appliances less energy-efficient and more costly, it is also damaging to the environment. Heating elements covered in limescale make them significantly less efficient which can have an impact on your heating bills.

Water Purification

Limescale can be prevented by using a water purification system. At Aquatec – the Pure Water People we offer home waters systems that soften water, removing the minerals that cause limescale. All of the problems we’ve discussed in this article will simply no longer exist.

If you want to find out more about what limescale is and how our Aquatec – Pure Water People water purification systems work then give us a call on 0117 9109988, request a call back or fill out our online enquiry form