Your car is coated in dirt and a quick spray with a hose isn’t going to cut it. So, you hire a professional car detailing service to get the job done right. The technicians come out, pull out all of their equipment, and hook their hoses up to your domestic water supply.
You’ve just seen a major red flag.
And you may not even know it.
Your detailer isn’t using deionized water if they’re plugging straight into your house’s water supply. That could mean major problems for your car. Here, we explain what deionized water is and why any professional mobile car detailing service in Mesa AZ should only be using deionized water!

What Is Deionized Water?
The clue is in the name – deionized water. It’s water that has had all of its ions removed. An ion is any atom that has either a positive or negative electrical charge due to the addition or removal of electrons to or from a neutral atom. That’s the super technical description. When it comes to car detailing, these ions are found in the minerals present in your domestic water supply. Those minerals can include calcium, magnesium, iron, and a whole raft of others.
The mineral levels of your domestic water are regulated (usually by the state) to be safe for human consumption. In many cases, the presence of those minerals is actually positive. Your body needs calcium and iron, and your water can be a helpful source for reaching your daily required amounts.
So, why deionize water at all?
It all comes down to purity. Deionized – which is not the same as distilled water – purifies your water by removing ions from the equation. That’s often useful in chemistry experiments where the presence of even a handful of microscopic molecules could skew the results.
Why Should Your Mobile Detailing Services Use Deionized Water?
Deionized water is useful in science, then. But what does it have to do with professional car detailing? The answer is that detailing a car is a lot like a chemistry experiment. Your mobile detailing service uses chemicals and has to consider the impact those chemicals – combined with the ones in the water – have on your vehicle. The following are detailed reasons why your detailers should use deionized water.
Reason 1 – Confronting the Hard Water Problem
The water that flows from your faucets contains minerals, including calcium and magnesium, as we explained earlier. The amount of those minerals in your water determines the water’s hardness level. More calcium and magnesium lead to harder water. In scientific terms, water is classified as “hard” when it contains between 121 and 180 milligrams per liter (mg/L) of these minerals, going up to “very hard” at above 180mg/L.
The problem from a professional car detailing perspective is that these minerals cause problems when washing your car. They can create micro-scratches in your paintwork and even embed them into the car’s paint to cause discoloration over time. So, a good detailer uses deionized water to ensure that your hard water doesn’t end up damaging your vehicle during cleaning.
As an aside, most American states have hard water. Indiana, Nevada, Minnesota, Texas, Florida, and Arizona notoriously have some of the hardest water. A detailer in those states and a few others has to use deionized water to counter the problems hard water presents.
Reason 2 – Improved Cleaning Efficiency
There are ways to counter the hard water problem besides using deionized water. A detailer who’s aware of the problem can take extra time to ensure that the water spots hard water leaves behind are wiped away immediately. But even that isn’t a perfect solution – wiping water spots that contain ions can cause the micro-scratches we mentioned earlier.
The problem is that accounting for hard water takes more time. It interferes with the cleaning process, which creates more work and, in some cases, could lead to your detailers charging more than they otherwise would for cleaning your car. Using deionized water eliminates the need to meticulously ensure your car has a spotless finish, leading to lower costs and a much more efficient detailing experience.
Reason 3 – Reduced Water Usage
The efficiency issue that comes with using ionized water doesn’t only involve the time taken to clean. It’s also an issue when it comes to water conservation. Your detailer has to use more water when they plug into your domestic supply because they’re compensating for water hardness. They’ll combat water spots with even more water before wiping and might have to use additional water to get rid of mineral stains if you have exceptionally hard water.
Using deionized water means less water is used overall when detailing your car. That’s key in Arizona, for instance. The state is already moving from water stress to being on the verge of water scarcity, according to the University of Pennsylvania’s Water Center. Using more water than needed to clean your car contributes to that state-wide problem. Deionized water is a smart solution.
What It All Comes Down to – Deionized Water Leads to a Cleaner Car
Full mobile car detailing services that use deionized water clean your car better than those that don’t. They’re using water that doesn’t leave behind unsightly spots and stains and are more efficient in their cleaning processes. Plus, deionized water is great if you want to prep your car for waxing. You don’t have to remove minerals and other impurities caused by hard water prior to waxing when your detailer uses deionized water.
So, consider your detailer’s water choice as a factor when choosing the right service. If they’re not using deionized water, they’re not the best choice for your vehicle.