Evidence on how the fire started and why it spread will take many weeks to assemble, and the MSM can perhaps be forgiven for their confusion. The BBC is reporting that the fire started on the ninth floor and spread to the eleventh; the guardian that it started on the fourth. The image below suggests it started on the fifth floor and spread vertically through the structure to the eleventh, where the fatalities are reported to have occurred.
So why is this important? Well, for those of us involved in construction, understanding part B of the building regs is fundamental to managing the design of large or complex buildings. The principle is that buildings are constructed in fire resistant compartments, with both horizontal and vertical compartmentation; that individual dwellings also each have a protected lobby to prevent fires spreading to common corridors, and corridors and stairs should be specially protected and in particular that linings should be fire resistant.
I have two major concerns about the Camberwell building. Firstly, the fire appears to have spread vertically through the structure, from flat to flat. Secondly, the fire appears to have spread along an internal protected corridor on the eleventh floor (if the layout was as in the sketch plan below). Older buildings can have fire-stopping and cavity barriers inserted, as well as additional protection such as alarms and sprinkler systems. Those resonsible for reported recent building works will have valuable evidence to give.