vertical load
 

All buildings have mass made up from the mass of the materials used to make them, e.g. steel, concrete, timber, bricks.

When they are in use, they also carry additional mass inside from people and objects, e.g. equipment, furniture, books.
 
Vertical Load acting downwards.
 
The Earth's gravity is trying to pull this mass vertically downwards towards the ground which results in vertical forces being applied all over the building.

Civil engineers call these forces Gravity or Vertical Loads.
 
When you make a scale model of a building, its SIZE is reduced. However, the MASS of the building does not scale down correctly. The model is lighter than it should be. Your model must carry extra weights to correct for this problem.