External factors
Steel structures - Pathology of steel structures

Exceptional falls

In principle, the NV 65 and N 84 rules cover all regions of France for even the most exceptional snowfalls (extreme snow) likely to occur. However, precipitation can sometimes exceed the forecast values.

Accumulation

The phenomenon of snow accumulation poses a delicate problem for the designer. Regulations provide guidance on possible accumulations, but cannot anticipate every possible case. Estimates of specific loads may, in some cases, be necessary.