Daniel Jones, of Spawd Bone Lane, Knottingley, was instead found guilty of two counts of manslaughter after he used petrol to set fire of the home of Andrew Broadhead, 42, and daughter Kiera.
The jury took three hours and 18 minutes to return a unanimous verdict at Leeds Crown Court.
He was also found guilty of one count of burglary.
The court heard Jones, 29, had broken into a house near to their home on Ash Crescent, Stanley, three days earlier but returned in a bid to destroy possible incriminating footage from a CCTV camera at the property.
Mr Broadhead, his wife Sara, and their two children Kiera, and Mia, 13, had returned from holiday hours before the blaze.
The court heard Jones poured petrol through the front door letterbox and set it alight in the early hours of October 19 last year when the family was asleep.
Mrs Broadhead and Mia survived the devastating blaze.
Jones had previously told the jury that he did not light the fire or carry out a raid on the other house.
Mr Justice Norris remanded Jones in custody until Thursday, November 9 so that a pre-sentence report can be prepared by the probation service.