Wood is lighter than all other materials (reinforced concrete, steel, etc.). Despite its lightness, wood is resistant to tension and pressure, while reinforced concrete is not. As a result of an earthquake, reinforced concrete structures collapse as large blocks and crush those underneath, while wooden structures; however, they will separate from their joints and lean in one direction, so the area underneath will form a void and contain a living space, and since it is a light material, it will not pose a crushing or lethal threat.