Rather than spontaneously combusting; in a large bushfire that is generating firestorms, the pressure differential can cause nearby houses to literally explode.

Rather than spontaneously combusting; in a large bushfire that is generating firestorms, the pressure differential can cause nearby houses to literally explode. My late uncle who was at the Mt Macedon fires during Ash Wednesday told the story of getting trapped by the fire and sheltering with another firefighter in a house that was ripped apart around them - they ended up sheltering in a concrete toilet block as the fire raged past. These type of fires create their own weather.