Foundation & Structural Safety - Foundation size is not visual guesswork – it must be calculated, not decided “by the eye.” - Common mistake in self-construction – using the same footing/shoe size for all walls, regardless of span or column spacing. - Structural hazard – ignoring span differences can lead to unsafe foundations and beams. - Relationship between span (light) and section size – shorter spans (e.g., 3.1 m) require smaller sections (26×26 cm), while longer spans (e.g., 5.5 m) demand