Two crews from Gamlingay and Huntingdon were called to a fire in a derelict outbuilding on a farm in Gransden Road.
Firefighters wearing breathing apparatus used a hose reel to extinguish the fire in the building, two metres by four metres, before returning to their stations for 7.48pm.
The fire had started after rubbish that was being burnt in an oil drum set fire to the outbuilding when the wind picked up.
Watch Commander Andrew Davis said: “Please ensure you are aware of weather conditions when having a bonfire.”
Top tips if having a bonfire include lighting the fire well away from buildings, sheds, fencing and shrubs/trees; staying with the bonfire until it is out; keeping children and animals away from the fire and not lighting bonfires if it is breezy.
For more information see our bonfire safety visit our outdoor safety section.