Problem
Few buildings will be structurally and socially intact, unless the floors step down toward the ends of wings, and unless the roof, accordingly, forms a cascade.
Solution
Visualize the whole building, or building complex, as a system of roofs. Place the largest, highest, and widest roofs over those parts of the building which are most significant: when you come to lay the roofs out in detail, you will be able to make all lesser roofs cascade off these large roofs and form a stable self-buttressing system, which is congruent with the hierarchy of social spaces underneath the roofs.
Related Patterns
… this pattern helps complete the Building Complex (95), Number of Stories (96), Main Building (99), and Wings of Light (107), and it can also be used to help create these patterns. If you are designing a building from scratch, these larger patterns have already helped you to decide how high your buildings are; and they have given you a rough layout, in wings, with an idea of what spaces there are going to be in each floor of the wings. Now we come to the stage where it is necessary to visualize the building as a volume and, therefore, above all else, as a system of roofs.
Make the roofs a combination of steeply pitched or domed, and flat shapes - Sheltering Roof (117), Roof Garden (118). Prepare to place small rooms at the outside and ends of wings, and large rooms in the middle - Ceiling Height Variety (190). Later, once the plan of the building is more exactly defined, you can lay out the roofs exactly to fit the cascade to individual rooms; and at that stage the cascade will begin to have a structural effect of great importance - Structure Follows Social Spaces (205), Roof Layout (209).
Alexander, Christopher. A Pattern Language: Towns, Buildings, Construction. Oxford University Press, 1977, p. 565.