He was flown in a serious condition to Whangārei Hospital by the Northland Rescue Helicopter, then to Middlemore in Auckland which has a specialist burns unit.
Fire chief Craig Rogers said two fire trucks and a tanker responded from Kaitaia, plus one truck from Ahipara.
The house was well ablaze even as they left town, he said.
Fire chief Peter Cullen said it was fortunate residents manage to contain the fire before the brigade arrived, because it had potential to spread to other dwellings nearby.
The caravan was destroyed but no one was hurt.
The fire was thought to have been started by a candle, Cullen said.
About 1.30pm on Sunday the Kaitaia Fire Brigade was called out again, this time to a vegetation fire on a property next to Paparore School, about 20km north of Kaitaia.
The blaze, which covered an area of about 20m x 50m of grass and scrub, was thought to have been started by an illegal rubbish fire.
Kaitaia and the Aupōuri Peninsula are currently subject to a total fire ban.