Add Slab by Click

                                  
Creates a slab in a room, defined by a closed set of walls.

1. Start with a set of closed walls.
   
2. Open the tool's Properties and define the slab style on the General page. See Slab Styles. You can also change a slab's style using the Selection Info palette.
3. Activate Add Slab by Click and click anywhere inside the room.
   
   The slab is created inside the room, between the walls.
   
4. You can also specify to offset the slab from the walls by using the Offset field in the Inspector bar.
   
5. The thickness and area of the slab are listed in the Selection Info palette.
   

Local Menu Option 

Use Wall Thickness: This option can be useful using walls with different widths. If this option is selected, the offset value for each side of the slab will be calculated separately as offset = offset*wall_width In this case offset value is dimensionless quantity and acts as a multiplier of the wall width.