You define floor slabs and beams manually with the slab meshing tools. Drawing elements manually requires more thought on the drawing process. Poor decisions could require a significant amount of editing and duplication of work.

Drawing elements manually also requires careful application of the tools to ensure that the side of each element is the same length as the adjacent element. In other words, each element node must be at the corner of any element that touches it. Elements cannot overlap.

You model beam elements as thickened slab elements with the same slab element tools. You model openings as empty spaces in the mesh.