ArchT has two categories of roofs:

Primary: A primary roof can stand alone on a structure. It is the main roof covering a structure.

Projected: A projected roof intersects other roofs or 3D faces. You can project roofs onto any 3D face. For example, you can project a gable roof onto a hip roof or onto a wall face.

You can create the following types of primary and projected roofs:

• gable
• hip
• gable hip (primary only)
• shed
• polygon
• ridge (projected only - projects between two roof planes)

When creating a complex roof system that consists of several primary and projected roofs, you should create the primary roof section first. Because the other roofs project onto this roof, it should be the highest and widest roof. Using this method of construction and the basic roof types provided in ArchT, you can place a roof over almost any type of structure.

In ArchT, the various components that make up a roof are grouped into an assembly. A roof assembly consists of the following components: fascia, roof exterior, roof interior, and soffit. Each component can have different properties: layer, linetype, color, and material.