Fact check: Pouring hot water on a frozen windshield can cause damage

Social media users have been sharing posts that advise drivers to pour hot water on the windshield of their car to defrost it faster. This claim is false.

Reuters Fact Check. REUTERS

Examples can be seen here and here .

One post here reads: “Pour hot water on your windshield & it’ll defrost faster thank me later.”

The United States was hit with a winter storm this week that left usually warmer states unprepared against the cold. The weather has shuttered COVID-19 inoculation centers and hindered vaccine supplies (here).

The American Automobile Association (AAA) and the Automobile Association (AA) both recommend against using hot water on a windshield, which can crack or shatter glass due to the sudden change in temperature ( here , here ).

Instead, the AAA recommends starting the engine, setting the heater to “defrost”, adjusting the airflow to recirculate and moving the temperature control to full heat. As the ice melts, drivers can use a plastic scraper, the windshield wipers, rubber squeegee or a soft brush to remove the ice off the glass (here).

Glass companies around the country also advise against using hot or warm water on windshields in cold temperatures ( here , here and here ).


False. Pouring hot water over a car’s windshield during low temperatures can damage it, causing it to crack or shatter from the sudden temperature change.

This article was produced by the Reuters Fact Check team. Read more about our fact-checking work  here  .