A SETTEE, blinds and other furniture were damaged when an arsonist launched an attack through an open window.
Detectives believe a lit piece of paper or something similar was pushed through the window at the back of the house in Robert Street, Seaham, between 5pm and 8pm, on Sunday.
The householder came back from visiting a friend to find the aftermath of the blaze, which had died out on its own.
In addition to the ruined furniture, the room was left smoke damaged.
An inspection by the fire service after police were called in confirmed the blaze was started maliciously.
Officers say whoever started the fire entered the rear yard of the terrace house.
They have appealed for witnesses who can help investigations.
Anyone with information about the incident is asked to contact Durham Constabulary on 101 or Crimestoppers on 0800 555 111.