Nobody was in the property, which suffered damage to its first floor.
Firefighters were called to a house fire in Bideford on Saturday afternoon.
Crews from Bideford and Appledore were called to the bedroom fire in Newton Road.
Police closed the road while the fire service used three pumps to extinguish the blaze.
Group commander Jon Worsley said the origin of the fire was not yet clear and confirmed no one had been in the property when the fire took hold.
He added: “The fire’s knocked out, we’re going to put a pressure ventilation fan on the front and blow any products of combustion that are left in there out, then we can go in without our breathing apparatus.
“Once we can get in and have a good look upstairs, we’ll get to work out exactly where the fire started and will give us more information of the origins.”
The first-floor bedroom was 100 per-cent damaged by the fire, with the ground floor sustaining light smoke damage.
It is not thought the fire in the semi-detached home spread to the property next door.