Walls, floors, ceilings, and roofs can be composed of parallel layers. A layer can consist of a single continuous plane of material (such as plywood) or multiple materials (such as gypsum board, studs, insulation, air spaces, bricks, and sheathing). In addition, each layer within the component serves a particular purpose. For example, some layers provide structural support, while others act as thermal barriers. Revit considers the function of each layer and matches the layers appropriately.
You can represent each layer by setting the layer's material, thickness, and function. You typically see compound geometry in floor plans, reflected ceiling plans, and sections. They display in hidden line and wireframe views. See and .
7-layer wall shown in plan view