Karl Swales, 47, set fire to a pizza box and clothing in his doorway, then let the flames smoulder as he walked out of the three-storey building in Trafalgar Square.
York Crown Court heard that Swales had earlier dismantled four fire alarms or smoke detectors inside the elegant Victorian townhouse in Byrons Court.
Smoke drifted down the stairwell and when the landlord went up to Swales’s attic flat, he found a smouldering fire eight inches high next to a pile of clothes, a pizza box and other combustible materials, said prosecutor Rob Galley.
The landlord managed to douse the flames and Swales was arrested. He was hauled in for questioning but when police asked him if he started the fire, he replied: “Well, I could have done.”
He told officers he had dismantled the smoke detectors because he thought they were cameras which were filming him.
But he admitted a charge of arson and being reckless as to whether life would be endangered, as well as further charge of damaging fire alarms and a carpet.
Swales appeared for sentence via video link on Thursday when Judge Paul Batty QC jailed him for 32 months.
Prosecuting barrister Mr Galley said the fire had been smouldering for about five minutes and was a foot high by the time the landlord reached Swales’s unlocked and messy attic room on the top floor. Children were among the tenants living in the building.
He said although the removal of smoke alarms would ordinarily present a clear risk to life in the event of a major fire, the building’s fire-detection system and heat sensors were still in place and alarms sounded when smoke spiralled down the staircase.
He added that the landlord was due to inspect Swales’s flat with a view to eviction before the “small fire” on September 12, six days after Swales removed the smoke alarms.
The court heard that Swales believed his accommodation was “inadequate”.
A fire investigator said Swales had set light to clothes with a cigarette lighter. The carpet around the doorway had melted and cigarette butts littered the area around the seat of the fire.
Swales told police he had drunk half a bottle of vodka and taken prescription drugs before the incident.
Mr Galley said Swales had 21 previous convictions for offences including theft, deception, low-level violence, threatening behaviour and resisting a police officer. He was on a community order for shoplifting at the time of the arson.
Defence barrister Alex Menary said that Swales, who had stolen in the past to support his drug habit, had mental-health problems and became “acutely psychotic” following his arrest and remand in prison, where he was now on medication.
He added that Swales was “clearly a disturbed man and he thought the smoke alarms were cameras.”
Judge Mr Batty QC said the arson appeared to be “some form of payback in respect of what you perceived to be inadequate housing”.
Jailing Swales for two years and eight months, he told him: “Your flat was in a complete mess and it was no surprise that your landlord wanted you evicted.”