Which roof type is least likely to be used in areas with heavy snowfall?

Flat roofs are typically the least suitable for areas with heavy snowfall. This is primarily because flat roofs have a low slope, which makes it challenging for snow to slide off easily. When significant snowfall occurs, the accumulation of snow can lead to increased weight on the roof, potentially causing structural issues or even roof failure if the load exceeds the designed capacity.

In contrast, roof types like gable roofs, hip roofs, and shed roofs have slopes that allow snow to slide off more easily, reducing the risk of accumulation and the inherent risks associated with heavy snowfall. Gable roofs, for example, are designed with two sloping sides, which effectively directs snow away. Hip roofs feature slopes on all four sides, providing enhanced stability and snow runoff potential. Shed roofs have a single slope that facilitates snow sliding off one side, which is also advantageous in snowy conditions.

Considering these factors, flat roofs are indeed the least appropriate choice when it comes to addressing the challenges posed by heavy snowfall.