Water hardness is measured in degrees of German hardness (°dH) and describes the concentration of calcium and magnesium minerals in the water. When heated, these minerals precipitate as calcium carbonate – better known as limescale or limescale deposits.
The higher the water hardness, the more limescale deposits form. This can lead to higher energy consumption, increased strain on heating elements, and a shortened lifespan for household appliances. Furthermore, hard water reduces the effectiveness of soaps and cleaning agents, often requiring a higher dosage.
The quality of drinking water in Germany is regulated by the Drinking Water Ordinance. This ordinance sets out, among other things, requirements for the quality of drinking water and its regular monitoring.
The hardness of drinking water varies depending on the region and its source. Unlike in the Netherlands, there is no nationwide minimum water hardness requirement in Germany. Most water suppliers publish the water hardness for their supply area.
Water hardness is determined by its calcium and magnesium content. The higher the concentration of these minerals in the water, the harder the water.
The following classification is frequently used:
Water hardness varies depending on the region and sometimes even within individual municipalities. This is because drinking water is sourced from different sources. Therefore, the water composition can differ significantly from region to region.
You can easily find out the water hardness at your place of residence by contacting your local water supplier or by looking it up on their website.
even with a water hardness of around 2.7 °dH . The harder the water, the more pronounced the limescale buildup. This can have several consequences, including:
A water filter can reduce water hardness to an optimal level. This significantly reduces limescale deposits without completely softening the water.