How Does Hard Water Affect Laundry?

by Rachel Bray

Everything you need to know about hard water and your laundry


Freshly laundered clothes should feel soft and look clean. If you’ve ever wondered why your clothes seem a bit dingy-looking, feel stiff and harsh, or have white marks on them you might live in a hard water area.

There are ways to combat the effects of hard water on laundry, but first you need to know what you are dealing with.

What is hard water?

Hard water is water that contains high levels of dissolved minerals.

When rain falls over areas with impervious rocks and little calcium it will only pick up trace amounts of minerals. This is known as soft water.

However, in areas with limestone, chalk, or gypsum the water percolates through these porous rocks. They are mainly made up of calcium and magnesium carbonates, bicarbonates, and sulphates and the water dissolves the minerals.

chalk quarry

The water that ends up in our taps in these areas will therefore have high levels of these soluble minerals.

What does hard water do to laundry?

The minerals in hard water can have various effects on your laundry. Your clothes might seem yellowish, or dingy-looking. They can feel stiff, and the fabric can feel harsh. You might even find mineral deposits are left on your clothes as white or grey streaks or marks.

Instead of cleaning your clothes the ingredients in your laundry detergent can attach themselves to the minerals. This is particularly true in the case of traditional, powdered laundry detergents.

Surfactants in laundry detergent reduce surface tension, allowing dirt that wouldn’t normally dissolve in water to be dispersed. Non-ionic surfactants are resistant to hard water, so they don’t form the scum that anionic surfactants form when in contact with these minerals.

Traditional liquid laundry detergents contain non-ionic surfactants. However, as manufacturers aren’t required by law to list the individual surfactants it’s impossible to know whether they contain ingredients that are known to be particularly harsh or likely to cause allergies.

How do I know if I live in a hard water area?

There are various indicators that will help you tell if you live in a hard water area, even if you don’t know your local geology. Minerals dissolved in water will form deposits. Limescale is an obvious one. If you get a build up of limescale in your kettle, iron, or around your taps you’ll know about it.

gloves and sponge to clean dirty tap

If you regularly rinse out your kettle to get rid of all the bits you’ve got hard water! Not just annoying and unsightly, these deposits can clog pipes and cause plumbing problems.

Hard water will also make it more difficult to create a lather from soap or shampoo. You may also find a ring of ‘scum’ around your bathtub as the minerals in hard water react with soaps and form a solid, creating this scum.

And, of course, you might find that your laundry is not as clean or soft as it should be.

What can I do to avoid the problems of hard water associated with laundry?

Hard water is easily dealt with by using more detergent and higher temperatures. Using a laundry detergent with a lower proportion of non-ionic surfactants will mean you’ll need even more detergent and higher temperatures to get the same result.

However, instead of using traditional laundry detergent powders, liquids, or gels – and there are so many reasons you shouldn’t be using traditional laundry detergents that you can read about on our blog – use Melt laundry detergent strips.

In hard water areas you’ll still need to use more (you might find you need two or two-and-a-bit strips instead of one for a standard load of washing), but you won’t need higher temperatures.

Laundry strips work in hard water

Our strips don’t contain any harmful or toxic chemicals. They contain non-ionic surfactants to deal with hard water, and our formulation combines charged nanoparticles and patented "target" bio-enzymes without any bulkers. They dissolve immediately in low water and at cold temperatures.

Super concentrated, they’re light and environmentally friendly on all levels. No plastic is used, and they’re packaged in recycled, recyclable cardboard. They’re even available on a subscription basis and are small enough to be posted through your letterbox.



Join us now by subscribing to Melt Infinity. You’ll be doing something positive for the environment, your convenience, and your clothes!