A Guide To Using Shampoo Bars In Hard Water

The performance of natural shampoo can be affected by hard water. This article explains why and details some of the workarounds available should you want to continue using Friendly Soap’s natural shampoo bars in a hard water area. 

What is hard water?

Hard water is any water that contains high levels of the minerals calcium and magnesium. These minerals are absorbed by water as they pass through limestone, chalk, or gypsum deposits on the way to the sea. The hardness of your water, therefore, depends on the geological makeup of where you live. For instance Yorkshire, with its sandstone bedrock, has soft water, whereas Kent, with its white chalky cliffs, has very hard water. Hard water is not harmful in and of itself; in fact, it can even be good for your teeth! However, it can cause numerous problems, ranging from limescale build-up to a lack of lather when you’re scrubbing up in the shower.

Why is there a problem with shampoo bars and hard water?

The problem with hard water and natural shampoo bars arises when the calcium carbonate present in hard water bonds with the sodium salts in natural shampoo, creating a residue that cannot be washed out with more residue-creating hard water. This can leave the hair feeling heavy, dull and greasy and, in the worst-case, can even leave a white-grey residue in the hair. You can read more about the pros and cons of natural shampoo bars here.

Will this happen to me?

The short answer is, we don’t know. Not everyone who uses our Shampoo Bar in hard water areas will have a problem. We have lots of happy customers who use our bars with hard water and have no issues at all. This is because water hardness can vary even within designated hard water areas. So, unfortunately, the only way to find out is to give it a try.

If you do realise that your shampoo bar’s performance is being affected by hard water, but you're determined to use our products anyway, it is possible, but it is not without an extra little bit of effort. 

How to use a shampoo bar in hard water

Firstly, make a bicarbonate of soda solution by adding one tablespoon of bicarbonate of soda to one cup of warm water. Increase volume as necessary. Apply the solution to the hair and massage in as you would a shampoo. This will separate any residue from the hair. 

This should be followed with an apple cider vinegar rinse. Vinegar softens hard water, so by rinsing with it, you avoid the problem of trying to rinse out the residue created by hard water with more residue-creating hard water!

To make an ACV rinse, use one part ACV to four parts water. You will probably need more of this than you did the bicarbonate of soda solution. Rinse the hair thoroughly, until all of the baking soda solution and any residue left from the shampoo is removed.

At this point, you can experiment; some people find that after using an ACV rinse their hair is soft and shiny and there is no need to use a conditioner. Other people find that it can leave their hair a little dry and that a conditioner is necessary. Our Conditioner Bars do not contain sodium salts and so can be rinsed out with hard water.

We understand that this is quite a long-winded process and is something most people simply do not have time for. However, on the plus side, many people report that after making the transition to natural shampoos, they do not have to wash their hair anywhere near as regularly as they did with detergent-based bottled shampoos. This is because detergent-based shampoos strip the hair of natural oils, inadvertently triggering the scalp to produce more oil, which then needs removing more frequently. Many of our customers tell us that after transitioning to natural shampoo bars, they only need to wash their hair once a week.

Is there anything else you can do?

If you’re looking for a more permanent, less high-maintenance solution, water-softening shower heads are relatively inexpensive and have the added bonus of boosting the lather of any other natural soap products you use, whilst protecting your shower from limescale build-up.

Are you in a hard water area?

We have collected a list of the areas of the UK that are considered to have the hardest water

* Numbers represent calcium carbonate levels ppm or mg/l