Firefighters from Bracknell and Wokingham were called out by the woman living in the flat in Horatio Avenue at 12.20pm and spent an hour extinguishing the flames and safeguarding the home.
The tumble dryer broke and smoke filled the flat prompting the woman to evacuate the building and call for help on her mobile.
Watch manager Gary Condie said: "What we would like to say is it's important not to leave your tumble dryer on when you go out.
"Luckily enough, the resident was inside when it happened. If she hadn't been, it would have been a lot worse.
"Electrical items are usually very, very safe but, on an occasion when they catch light, if no one is in, it will cause a lot more damage without someone protecting it."