The house in Milton Road was undergoing renovation on the roof when the machine burst into flames, just before 9.30am on November 17.
It is believed that builders escaped the flames by jumping from the top floors onto the railway bank at the back of the building.
House fire in Milton Road, Gravesend (c.) Bindi Burrha
TOP STORIES: Gary Mills, 63, who owns second-hand furniture shop, Just-a-Second, in Milton Road said: "It was a shock.
"I saw the smoke and phoned the fire brigade.
"It was catching hold fast."
Firefighters tackled the flames at the three-storey house opposite Park Place for nearly four hours.
The roof was totally incinerated at house in Milton Road, Gravesend
Luke Randall, 25, of Lignum Carpentry and Construction, was working in the house next door when fire broke-out.
He told News Shopper that some damage to the roof next door was sustained as a result of the fire.
Kent Fire and Rescue Service (KFRS) were called to the scene at 9.27am.
Crews wearing breathing apparatus carried out a full search of the property but confirmed that everyone had been accounted for.
Mr Mills said that firefighters approached the roof from the top aiming the hose down at the flames
A spokesman for KFRS said: "Four fire engines and a height vehicle were at the scene.
"Firefighters used main jets and hose reels to tackle the blaze affecting the roof and all floors of the building.
"The fire is believed to have been caused by a failed generator.
"We stopped our operations at 1.15pm."
A spokesman for the South East Coast Ambulance Service said: "We attended the scene to support the fire service.
Firefighters were at the scene and tackling the blaze with (c.) Simon O'Brien
"No people were inside the house and there were no injuries."
Renovation work on the building is underway.
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