In Canada NM is restricted to buildings of combustible contruction. The type of construction is mandated by the building code and that is 4 stories here. A 14 story building is not combustible construction and NM cables may not be used.
This is consistent with the intent in the NEC.
BC is in the process of increasing the height to 5 stories but so far no one is trying to build 5 story wood frame buildings.
A political move by the provincial government to increase the market for BC lumber. Frankly I think it is insane to go higher than 4 stories and 3 is still a hard building to escape in a fire if it is built out of combustible materials.
We have a 22 story concrete building that has had 3 or 4 fire in the suites without any secondary loss of life even from high floors There is a lot more time and ways out of non combustible buildings bur most fire departments cannot get ladders higher than 60 feet whis is around where a 5 story building roof would be.
Keep the NM cables out of high rises.
