The rain‑repellent treatment, or hydrophobic treatment, is a liquid made of acrylic resins and transparent polymers that acts as a protective layer on the car’s glass. This layer helps to improve visibility on rainy days.

In general terms, this compound allows rain droplets to slide off more easily. It also has additional functions depending on the season: in cold weather, the rain‑repellent treatment reduces the likelihood of the glass freezing, and in hot weather, it acts as a shield against insects and dust. It therefore works as a complement to the windshield wipers to make driving easier and improve visibility behind the wheel.

At Ralarsa, experts in automotive glass for more than 40 years, we’ll explain everything you need to know about rain‑repellent treatment. In this article, we describe how to apply the treatment, its cost, its uses beyond rainy days, and how long it typically lasts.

How to apply rain‑repellent treatment

We’ve previously discussed the ideal time to apply a rain‑repellent treatment, which we recommend you read before starting the process.

The application process is quick and effective, and can be summarised in 4 steps, taking about 5 minutes in total:

  • 1. Professional cleaning of the windshield. Before applying the liquid, it is important to clean the glass so the product doesn’t mix with dirt.
  • 2. Applying the right amount of product. A small amount is applied to a clean cloth.
  • 3. Even spreading across the windshield. The product is spread in a circular motion to cover the whole glass evenly.
  • 4. Drying. Once applied, the product is left to dry so the layer adheres to the windshield.

Once complete, you’ll already notice improved glass clarity, especially when it rains. This process is highly recommended before a long trip — particularly to a rainy area — to improve visibility on potentially tedious and unfamiliar routes.

How much does rain‑repellent treatment cost?

Now that you know what rain‑repellent treatment is and how it’s applied, let’s talk about cost. At Ralarsa, we perform the full procedure professionally for €9.99 (VAT included) when you book online. Our process includes every step listed above and also helps extend your windshield’s lifespan.

How long does rain‑repellent treatment last?

Rain‑repellent treatment is quick and easy to apply yet offers long‑lasting results. The effect begins immediately and, although it gradually fades, it continues to work for quite some time.

It’s difficult to give an exact duration, as it depends largely on usage, temperatures, and weather conditions the vehicle faces. On average, the protective layer lasts up to 15,000 km driven — roughly a year under normal use.

Is rain‑repellent treatment useful without rain?

Although it may sound contradictory, rain‑repellent treatment can be very useful even on the driest days of the year. As a protective layer, it not only makes raindrops slide off faster, but also prevents road debris — like insects or dust — from sticking to the glass permanently, making it easier for windshield wipers to clean.

Your rain‑repellent treatment with Ralarsa

Now that you know what rain‑repellent treatment is, we invite you to visit one of our workshops and have it applied to your car. We are a network of specialists in automotive glass with over 40 years of experience.

You’ve already seen how affordable rain‑repellent treatment is at our workshops. Book an appointment at any of our 240+ locations nationwide — we’re available 24/7 for any queries. Protect your windshield with us!