An extension lead connected to an iron sparked into flames and ignited a bed in Doncaster on Thursday morning.
The fire at a house on Wheatley Hall Road started at around 10.45am.
An older woman was inside the house but managed to escape safely. She was given oxygen therapy by firefighters and was later taken to hospital by ambulance suffering from the effects of smoke inhalation.
Adwick, Doncaster and Edlington fire crews put out the blaze using a hose reel.