Firefighters were called to a fire in a house in Marrick in Swaledale early on Sunday.
The blaze was reported at 2.37am.
Appliances from Reeth and Richmond attended the incident.
They arrived to find the occupant of the property was out of the premises and the fire was confined to the airing cupboard.
Crews used breathing apparatus, a thermal imaging camera, a triple extension ladder, lighting and a hose reel jet to extinguish the fire.
North Yorkshire Fire and Rescue Service said the fire was caused by radiated heat from a light source onto camping equipment.
The damage sustained in the fire was confined to the airing cupboard.