Overhead vs Underground

This toggle decides where conduits run:

• Overhead — routed in the ceiling space. Runs hang below the slab, follow ceiling grids and avoid structural beams.
• Underground — routed below the slab, through slab penetrations and along floor-to-floor vertical paths.

In Overhead mode the diagram reads top-down: the Floor above line sits at the top, the Preferred Routing Zone (R) hangs just below it, and E is the rise from the panel up into that zone.

In Underground mode the diagram flips: the panel sits at the top with the Top of Slab line, and the routing zone drops below the slab. You still type positive values for R and E — ABR automatically places the zone below the level for you.

Underground routing also unlocks the Duct Bank module.