Why does a fogless shower mirror fog up?

Shower mirrors fog because the mirror surface is colder than the surrounding air, causing moisture to condense on the surface as tiny droplets or fog.

Some fogless shower mirrors function by preheating the mirror to repel condensation, while others have anti-fog agents making the mirror resistant to fog. Some of Mirrorvana’s shower mirrors use both principles in staying fogless, aside from having a built-in hot water reservoir, the mirror surfaces are treated with anti-fog coatings.

Here are some reasons a fogless shower mirror becomes fogged up:

  • For mirrors with anti-fog coatings, the anti-fog property may be depleted. You just have to reapply the coatings to restore its anti-fog property. You can check out Mirrorvana’s brand of anti-fog sprays that come in 1-pack and 2-pack.
  • For mirrors that use the warming method, the mirror may not be hot enough to repel fog. Make sure to keep the mirror warm or even warmer than the surrounding air by adding very warm or hot water to the water basin.

You can check out our Shower Mirror Collection on Amazon here


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