When a fire happens inside of a home or usually a smaller open space, soot webs occur when the smoke from the fire is lingering in the air for a long period of time. They form when ionized soot particles stick and chain together in cooler areas like corners and ceilings. This can happen in larger areas but over a longer period of time. If the smoke isn't properly filtered out of the affected property a thick black residue will form and then the soot webs form after that. When restoring a home after a fire like this, all surfaces must be scrubbed down with organic chemicals to rid surfaces of discoloration, soot, and odors.