An eggstone house construction diagram typically refers to a detailed illustration showing the step-by-step process of building a house made with river pebbles. This type of construction is common in certain regions, where local availability of materials and traditional building methods are favored. The diagram would include elements such as foundation, walls, roof, and interior design considerations using eggstone. Knowledge about traditional construction techniques, stone masonry, and local architecture is necessary to understand and interpret such a diagram.