Four fire engines and around 25 firefighters tackled a fire at a launderette with flats above on Waterloo Road in Southwark.
The ground floor of the six-storey building was partially damaged by fire. Around forty residents from the flats above were led to safety by firefighters. There were no reports or any injuries.
The fire is believed to have been accidental and caused by self-heating textiles.
A London Fire Brigade spokesperson said: "These types of fires often involve textiles that become contaminated with oil, most commonly linseed, massage and cooking oil on tea towels, tablecloths and chef whites. Make sure you check the manufacturer's cleaning recommendations of your textiles before washing.
"Sometimes when materials are cleaned and put in tumble dryers, the heat from the tumble drying cannot escape. This can result in a high enough temperature allowing it to build up to a point where it smoulders and eventually ignites.
"If you are washing and then drying on a hot cycle, always use the cooling cycle on the tumble dryer so it cools down and allow the heat to dissipate properly, before stacking laundered items together.”
The Brigade was called at 1927 and the fire was under control by 2036. Crews from Lambeth, Dowgate and Soho fire stations attended the scene.