Last Updated May 12, 2023
If you’ve ever had personal experience removing water spots from your car’s paint, you know how much of a chore it can be. At Dr. Beasley’s we emphasize preventative maintenance, so we’re here to discuss the benefits of detailing your car with distilled water.
Is Distilled Water the Same as Filtered Water? Is Purified Water the Same as Distilled?
Just to make sure we’re all on the same page, let’s talk about the differences between some water terminology of which you’ve certainly heard. You’re familiar with the notion of filtered water, which is not the same as distilled. Filtered is exactly what it sounds like, the water has been through a system of filtration to remove contaminants. Filtration does not remove all impurities, but it helps.
Distilled water has been through the process of distillation, which is when the water is boiled and the pure H2O is separated from minerals and other impurities. The H2O is collected and there’s your distilled water. Then there’s purified water. Water can be purified in a few different ways, and one of those ways is through distillation. Purification can also happen via reverse osmosis or deionization. So, distilled water is purified water but purified water is not necessarily distilled. Does that make sense? Hopefully!
Why Use Distilled Water?Now that we know that distilled water is pure, clean, and free from contaminants and minerals, why do we care? Well, undistilled water can be (depending on where you live) really hard. Hard water contains a large amount of minerals. You might be thinking, “what’s wrong with minerals? Minerals are healthy!” Not for your car’s paint. The minerals in undistilled water can leave spots on your paint. If the water is super hard and is left sitting, it can etch the surface. If a hard water spot etches, there is a semi-permanent outline of the water spot on your paint that has actually cut into the clear coat. This is where the real trouble begins.
Etching is incredibly annoying and can only be removed through claying and polishing. If you’ve got a matte car, you can’t clay or polish so etching is a true nightmare. If soft water were to be left on your paint for too long, it would still leave spots but they would theoretically be easier to remove because soft water doesn’t contain a high amount of minerals like hard water does.
The most important time to specifically use distilled water when dealing with your car is prior to/during the application of sealants and coatings. If you use undistilled water during the application of a protective coating or sealant, the product may not bond as well. You might also end up accidentally sealing IN water spots. To remove them you would have to remove the coating or sealant and then re-clean the car with distilled water.
So Do I Always Have to Use Distilled Water On My Car?Not ALWAYS. There are some coatings and sealants that go on wet. One example is our Formula 1201 coating. While the car is wet, you take the foam pad applicator with 1201 on it and panel by panel, you apply the coating. Water is absolutely necessary for the application of this product. Using distilled water is the best way to ensure the coating bonds properly. The minerals in hard water might impede or change the bonding process. We know some professional detailers who will ONLY use distilled water, whether they’re just cleaning the car or applying a coating. They stick with distilled because it’s overall much better for the health of the car’s paint. If your tap water is soft, it’s fine to use it to wash your car.
You just want to (as always) make sure you dry every inch of your vehicle after washing. If you’ve got hard tap water, avoid using it to clean your car. How can you tell if your tap water is hard? There are a few different ways to check and many of them are free. Do you have limescale on your faucets and shower heads? Does your skin feel dry after you shower? Is your glassware foggy looking after you wash it? All of these are indicators of hard water coming from your tap.
Finally
You can use undistilled water for regular washing if you’re sure your water isn’t hard and if you very completely dry the entire car after you rinse. If you’re applying a coating or sealant, always use distilled water. If your tap water is hard, consider using distilled water when you wash your car.
Wow! I never knew that there is an effect in the kind of water used to wash cars. Btw, would you recommend the use pressure washers? I have been searching and I stumbled on this page, http://idealpressurewasher.com. Btw, your blog is very informative for a new car owner like me. Thanks a lot!
Hi there,
We’re glad to hear you like Behind the Detail! Pressure washers are fine depending on how they’re used. We use them but always at a relatively low PSI. We usually use them after rinsing to get all the loose contaminants off first. They’re really great on wheel wells, bumpers, grills, etc. Let us know if you have any other questions, we’re always happy to help.
-Dr. Beasley’s Team
That’s great, but how does one source enough distilled water to wash/ rinse a car.
Yes, it’s expensive at the store, I’m not sure where they sell ‘bulk’ ,
I collect distilled in the summer months from my window ac units, I
have a drain from each that drips into buckets or water bottles,
I can get a gallon or so per day from each unit, but it really gets hot here in az. ,
probably can’t do as well in milder climates.
There are ways to set up parabolic mirrors to a ‘still’ type of device, but that
warrants specific safety precautions that many won’t want to get involved with.
Very nice. Nice work on the blog post.
http://www.akinscollisioncenter.com/
Thank you! We are glad to hear you enjoyed reading it.
Thanks, I thought distilled might be good for my car, thought I’d check , and here I am….
Much appreciated.
I was told if I rinse the car with distilled water I don’t even have to dry it and it will leave no water spots. The works power washer is a good tool to rinse the car down with distilled water. You just put the hose from the unit in a gallon of distilled water and spray it.
Haha no way i was gonna try the same tomorrow. First rinse with reg water to get all the soap off and then use Worx to rinse away hard water.