8. Force transmission

Load-bearing elements are subjected to vertical and horizontal forces due to the combination of various external stresses, and must be transmitted to stable points. The dimensioning of a structure starts with the upper parts, in the logical order: roof, framework, intermediate floors, walls, foundations.

The vertical loads to be taken into account are :

• permanent loads consisting of the dead weight of all materials used in the structure, 20% of operating loads (estimated at 150 kg/m ² for a dwelling);

• temporary loads, comprising 80% of operating loads and climatic surcharges (snow and wind).

Horizontal loads are mainly due to wind (§