Although it only takes a few minutes to scrape the window panes in the morning, it is nothing short of fun. And although there is cheap protection, most of the cars in the Czech housing estates – as we observed this week – had frozen windows. One car out of ten had the foil, which you can install in the evening in ten to fifteen seconds.

We tested in practice what would best help prevent icing. A curtain, bubble wrap, cotton fabric and an ordinary piece of cardboard – from a paper box from a supermarket or pizzeria – entered the fray.

A curtain for the front window with an aluminum layer is not expensive, it will cost about 100 crowns. The advantage is that you can close it to the door, so the wind won’t blow it away or steal it. You put it on in the evening and in the morning you don’t have to scratch the windshield. Simple and perfectly functional. Proven for the long term and thanks to the richly dimensioned shaping and perfect adhesion, there was no need to scrape the ice even once.

Photo: Martin Žemlička

Insulating film and a piece of cardboard can protect the glass from frost very effectively

However, if you want to save money or if you don’t have foil at hand, you can use paper cardboard. It works surprisingly well! In ten-degree frost, it protected the window of the tested Fabia as well as foil. However, after an all-night service, we could see some minor moisture damage on the cardboard. We calculate that one piece of cardboard could not be used for more than a few weeks…

The fabric (an old piece of textile) absorbed the most frost overnight. This is potentially a problem – stored inside the car would increase humidity and could lead to fogging of the windows from the inside later, plus it could mold. However, it worked very well as an insulator.

Photo: Martin Žemlička

On the left was foil, on the right was cardboard. Both variants worked very convincingly

Due to its lightweight construction, the bubble wrap had the disadvantage of sliding down the glass. If you’re a bit like Laďa Hruška, you could stick a foil in the shape of your car’s front window with insulating tape and functionality would be guaranteed. The advantage over cardboard and fabric is that bubble wrap repels moisture and is waterproof.

So who won? The winner of the unconventional test is the classic film, which has the best functionality and durability, and at the same time costs a lot. If you still want to save money, even a simple paper carton has proven itself.

Photo: Martin Žemlička

An old piece of rag or bubble wrap can also be effectively used against frost, but from a practical point of view it is somewhat problematic

What we cannot recommend, on the other hand, is defrosting the window using water. Even hot water poured on the glass does not work, moreover, the thermal shock will damage the structure of the glass and in the worst case, the glass may even crack. Lukewarm water won’t damage the glass, but it won’t freeze it either.

When the glass is frozen, you can either wait for the higher temperature or weak winter sun to thaw it effortlessly during the day, or you have to reach for a plastic scraper. You can buy it for 20 kroner at any gas station, and in an emergency, for example, a plastic card will help – but you’d better not try it with the payment card, so that it doesn’t get damaged and you don’t run out of money temporarily. Anyway, let it be spring…

How do you defrost the windshield?

Foil, cardboard, blanket on the windshield.

Hot water, I live life on the edge.

I have a heated windshield or I park in a garage, I just laugh in the winter.

A total of 6 readers voted.