Neighbours rallied to help by beating a grass fire threatened nearby houses with wet sacks, containing a grass fire until the fire service arrived.
Five fire units responded after the emergency call was received at 7.54am.
A large tree beside the house caught fire and was felled amid fears it could cause another grass fire downwind.
A fire service spokesman said when they arrived the house could not be saved and the firefighting effort went towards containing the fire in strong winds.
He said a spark from a lawnmower started a small grass fire yesterday and strong overnight winds likely caused the fire "from something smouldering underneath" the house.
The family is staying in Hastings.