Water Hardness in Your Area
The Thames Valley has some of the hardest water in the UK. Select your town to see the exact hardness level and find out what it means for your car's paintwork.
Why Does Water Hardness Matter for Your Car?
When water evaporates from your car's paintwork, it does not disappear cleanly. It leaves behind dissolved minerals, primarily calcium and magnesium, as a white or chalky residue. This is a water spot.
In soft water areas, these deposits are minor and easy to remove. In very hard water areas like the Thames Valley, the mineral concentration is so high that these deposits can etch into the clear coat within days, particularly in warm weather when the water evaporates quickly.
A cheap roadside wash that uses local tap water and leaves it to dry naturally on your paintwork is not just ineffective — it is actively damaging over time. The same applies to hosepipe washes at home.
At LXC Detailing, we use Spotless Water on every job. This is deionised water with all minerals removed. When it dries on your paintwork, it leaves nothing behind. No spots, no streaks, no etching.
Understanding the Hardness Scale
Water hardness is measured in milligrams per litre (mg/L) of calcium carbonate. The higher the number, the more mineral content in the water.
Every town in our service area falls into the Very Hard category. Most register between 287 and 329 mg/L, placing them among the hardest water supplies in the UK.