are you sure? it looks A LOT like cgi as the camera pans around. im actually certain at least some of the fire is cgi graphics and they did not burn that building. the smoke is definitely 100% cgi and it looks shyttier than the LOST smoke monster.
Yeah, they mentioned it on The Talking Dead. That structure was actually burned down but the rest of the fire within Woodbury was CGI since that's actually a town (Senoia, GA).