Should You Wash Your Car in Direct Sunlight?

Washing your car may seem like an “asked and answered” question, but many struggle with the idea of washing or not washing their vehicle based on the weather. Even detailing experts aren’t clear on if you should or shouldn’t wash your car in the direct sunlight.

Not Choosing Direct Sunlight

The first reason to avoid washing your vehicle by hand in the direct sunlight is the heat. Yes, too much heat could cause exterior damage to your car. For decades it’s been accepted among detailers that you should not wash your car in direct sunlight. Many have argued that doing so is bad for your vehicle’s finish and it can make the task of washing your car more difficult. The reasoning – the water and soap dries faster when in the sun or on a hot surface, because of this you’re more likely to get water spots when washing your vehicle outside in the direct sunlight.

The pros, who aren’t fans of washing vehicles in the direct sunlight, advise those who want to wash their cars by hand to keep the surface cool with a regular spray of water. It’s also not uncommon to see advisories on products from manufacturers suggesting users “apply the cleaning product on a cool, dry surface” and “to not use in direct sun.” But, you can in fact wash your car in direct sunlight.

The product disclaimer shouldn’t be seen as a “no”, instead it should be seen as a cautionary note. This is because in most cases you have to adjust your technique when working in the sun. According to a few detailing experts, manufacturers want to avoid having their product being at fault for any poor results, hence the blanket warning against using products in direct sunlight.

Choosing Direct Sunlight

For those who choose to wash their car in the direct sunlight, there are few notable benefits, aside from having a freshly cleaned car.

Here are a few tips to keep in mind to minimize streaks and other hazards if you need to wash your car in direct sunlight.

1. Don’t be afraid to use a pop-up tent. A lot of professional mobile detailers carry pop-up tents with them. It is important to note that most pop-up tents do take time to properly set up. This is the main reason why you don’t see many mobile experts use them on jobs.
2. Choose sun-friendly products. Product choice is important when choosing to wash your car in the sun. You could try using a rinse-less soap when washing your car. This option allows you to finish without spraying your vehicle with water to rinse off the soap.
3. Choose the right soap. If you decide you want to use a traditional method to washing your car, it’s important to choose a high-quality PH neutral soap. Using PH neutral soaps won’t cause damage if it were to dry on your paint.
4. Plan ahead. If possible you should try to have everything you need prepped before you reach for the water hose. Planning ahead is a benefit because once your car is wet you have a limited amount of time to complete your task before the sunlight starts to dry your products. It also isn’t a bad idea to wash other parts of your vehicle first, like the wheels, so you don’t have to take time away from washing the body of your car.
5. Timing is important. Your strategy has to change when you’re washing your car in the sun, according to professionals. Normally if you’re washing your car outside, you would cover your car with soap, but that plan isn’t the most time effective. It’s easier to complete a quality job when you wash smaller sections at a time. A good rule of thumb is to work panel by panel, or do half a large panel at a time, according to experts.