
Archicadwiki has a nice – because short and to the point – article about how to model flat or near-flat roofs using various interacting combinations of slab, mesh, and roof.

Archicadwiki has a nice – because short and to the point – article about how to model flat or near-flat roofs using various interacting combinations of slab, mesh, and roof.
We’ll expand on this later. Meanwhile:
Digtal Vision: comprehensive site modeling pdf.
Graphisoft help article on mesh techniques.
Bobrow’s exposition.