I'm not sure if I'm posting this in the correct section, but here goes...
My father had a fire in his bungalow over the Easter weekend. He noticed that after all the furniture and fixtures had been removed, the worst of the smoke marks seem to be where nails are and follow the cables and wires that are inbedded into the walls. Why would this happen?
volatile substances such as hydrocarbons from plastics and tar from wood products would condense on the coolest parts of the rooms such as areas of high thermal conductivity eg. metals such as nails, screws, conduit and wiring.