Firefighters rescued a man from the first floor of a house in Lausanne Road yesterday.
London Fire Brigade said it was called to the semi-detached home at around quarter-to-four in the afternoon after a woman called 999.
She reported that a smoke alarm had alerted her to a fire in a bedroom, and although she had been able to leave with the dog, her son was still trapped inside the house.
The man woke up but was unable to escape through thick, heavy smoke.
Emergency service operators spoke to him over the phone and told him to use towels at the bottom of his bedroom door to block out the smoke until firefighters arrived.
The man was rescued from his first-floor window and brought down a ladder to safety, before being treated at the scene for smoke inhalation by paramedics.
The brigade says the blaze is believed to have been caused by an extension lead electrical fault.
Four engines and 25 firefighters had the fire under control by just before 5pm the same day.