According to the London Fire Brigade, he did not require hospital treatment.
The fire happened on Perry Vale just after 6.30pm on Thursday (October 16).
The blaze destroyed a building consisting of a shop on the ground floor, a basement, and flats on the first and second floors, as well as a storage area to the rear of the shop.
Two people and a dog escaped from the flats before firefighters arrived, assisted by members of the public.
Around 15 people were evacuated from nearby buildings and taken to a rest centre.
Most were able to return home overnight, though a few remain in the care of the local authority.
Two 32-metre turntable ladders were deployed as water towers, and a drone provided situational awareness for incident commanders.
Smoke from the fire also caused the temporary closure of Forest Hill Station.
The fire was brought under control by 11.44pm and is currently being treated as accidental, believed to have started in the rear workshop during hot works.
Deputy Assistant Commissioner Jamie Jenkins, who was the Incident Commander, said: “Firefighters were met with a fully-developed fire and they worked extremely hard for several hours to prevent the fire spreading to neighbouring properties.
“This was a protracted incident with crews working through the night to fully extinguish the fire.
“We deployed two of our 32-metre turntable ladders as water towers to help put out the fire from above.
“Whilst the fire was ongoing, we advised people in the local area to keep their windows and doors closed due the smoke travel from the incident.
“This smoke travel also resulted in the temporary closure of Forest Hill Station.
“An investigation into this fire remains ongoing; however, I can confirm that the fire is being treated as accidental and is believed to have originated in a storage area.
“A small number of crews remain at the scene today extinguishing hotspots and assisting with the investigation.”
Forest Hill Station Commander, Mike Watts, said: “A 25-metre cordon remains in place and Perry Vale is currently closed to traffic; however the station reopened earlier this morning.
“The Brigade has worked closely with the local authority to support those affected by this fire.
“We will continue to have a visible presence in the area and will be liaising with local residents and businesses, sharing fire safety advice with them.”
