How do we get wood structures strong enough to hold second and third floors?

Question

How do we make houses and buildings out of wide wooden slabs that are strong enough to hold the people, furniture, and rest of the structure?

In: Engineering

Answer 1

In practice, by following building codes that tell you what size lumber to use where. Multiple stories isn’t particularly difficult, because the boards in the walls are loaded mostly in compression, whereas the floor is loaded in bending. The sheathing keeps those boards upright and also helps keep them from buckling. One of the boards in your wall can take thousands of pounds of force in compression if you can keep it from buckling, and there are many such boards in each wall.