Abbysmum said "I'm not an expert, but that's what I understand. That building would have had fire-rated drywall between units, doors on all units and probably sprinklers. All that would have slowed the fire, giving people time to escape and giving fire fighters a chance to contain it and prevent collapse. Fire happens often in multi-unit buildings, and often fires can be contained to a single unit.
Buildings under construction have zero fire suppression technology installed yet. It's basically a pile of tinder. So even a small fire can be a big disaster in a very short span of time.
So as dramatic as it is, we shouldn't be too freaked out by this. Modern building code has rules in place to prevent this type of collapse. "
Recently, a building in Winnipeg under construction caught fire just as quickly and burnt to the ground FAST. It was very similar, basically just wood framed.
Buildings under construction tend to be literal tinder boxes because as Abbysmum said, none of the fire suppression has been installed.
Buildings under construction are very vulnerable to fire.
Think back to the building on Pacific avenue. The top part was heavily damaged, but without the fire suppression systems built in, that building would have burnt to the literal ground within an hour or two, tops.
So while this fire was very fast and dramatic, a completed building would never burn like this.