Police are treating a Sleaford house fire as arson.
The alarm was raised shortly before midnight on Friday at the terraced property in Handley Street.
Fire crews gave oxygen to the only occupant of the house, Robert Cernigov, who had suffered from smoke inhalation. He said he had been asleep at the time after a shift working at the Mid UK Recycling plant.
Oxygen was given until ambulance crews took over.
Lincolnshire Fire and Rescue say there was fire damage to a mattress, which they found outside the address, and fire had spread to the downstairs bathroom and roof space at the rear of the house.
There was heat damage to the fascia board and guttering and smoke damage to the ground floor of the house.
Firefighters wearing breathing apparatus used one hose reel to put out the fire.
Mr Cernigov, who moved to the UK just over a year ago and rents the house, said the alarm had been raised by staff from Miller’s restaurant directly behind his house. Luckily his bedroom was at the front of the building.
He said it appears someone had set light to the mattress on purpose at the back of the house and the flames had spread, leaving holes in the roof of the blackened bathroom and melting the plastic bath fittings, causing toxic smoke.
Mr Cernigov could not understand why the fire had been started and by whom. He said: “The whole house was full of smoke and the firemen said I should go to hospital because I didn’t look too good.
“My landlord is contacting the builders and it may be two weeks before the bathroom is repaired.”
A small dam of sand was placed across the bathroom doorway and buckets spread around to prevent the rainwater through the damaged roof from spreading into the rest of the property.
Mr Cernigov said he was continuing to live in the house, though could not use that bathroom.
A police spokesman said: “Officers continue to investigate the fire, which is being treated as arson, and have appealed for anyone with any information that could aid the enquiry to contact Lincolnshire Police on 101 quoting incident 15 of 19/09/2015. Alternatively contact Crimestoppers anonymously on 0800 555 111.”