A family escaped through an upstairs window when fire broke out at their home in the early hours of this morning (Wednesday).
Flames had engulfed the wooden staircase when rags soaked in flammable floor oil ignited spontaneously.
Fire crews from Long Sutton and Holbeach attended just before 2.45am.
Firefighters wore breathing apparatus to tackle the blaze at the house in Gedney Road, Long Sutton.
Lincolnshire Fire and Rescue say there was severe damage by fire to the staircase, an under-stairs cupboard and its contents.
There was severe damage by smoke to the entire property.