Specialist fire investigators are expected at the home in Cleveleys where a man died yesterday.
Tributes have been paid to the man, who died despite the best efforts of neighbours - who fought to rescue him from the burning home - and paramedics, who gave him CPR after firefighters brought him out.
The Gazette is not naming him at this stage.
Writing on Facebook, Dom Haigh said: "Rest in peace, mate. I love you lots, brother. Forever in my heart."
Millie Williams wrote: "Thank you for being the best friend Caeran could ever ask for. You'll be missed."
And Hannah Tolmie said: "This really does put life into perspective. How devastating, and well done to people trying to help get him out."
Nearby roads were cordoned off by police as six firefighters wearing breathing masks and oxygen tanks searched the home.
They brought the man out and handed him over to paramedics, but he was pronounced dead shortly after, police said.
There were reports of loud bangs at the end terraced house, with several windows blown out, but they were being treated as 'incidental' by firefighters, it is understood.
A ladder, believed to have been used by a neighbour, was still leaning against an upstairs window this morning.
Witnesses described seeing the air ambulance helicopter in Cleveleys at around the time of the fire. It was pictured on the bowling green at the Park Club in West Drive.
Four fire engines were sent to the scene, two from Blackpool and one each from Bispham and Fleetwood, and arrived to find the fire 'well developed', a spokesman said.
Damage to the house was described by him as 'extensive'.
Another official said firefighters were met with a 'substantial' blaze when they arrived. They will be offered counselling.
Police have asked anybody with information to call 101, quoting incident reference 950 of June 2.
Nobody at the North West Ambulance Service could be reached for a comment.