Another posters query had me thinking. Is there any circumstance where a person can claim from their neighbours home insurance?? I am thinking of fire damage or water damage that may start in one house and damage an ajoining house for example.
So what if fire was caused by a cigarette.? Or what if someone had a crack in their house wall, which they ignored and a wall collasped damaging your home?
As Ravima said above, you would have to prove negligence. Doesn't make a difference if the cigarette was the cause of the fire, your own policy would pay out in the event of a fire claim.