In Florida, very few buildings have basements. Both
residential and commercial structures are built on
a concrete floor. Before the concrete is poured, electricians
may lay "conduit" (plastic or metal
pipe) in the ground. Electricians must be skilled
in blueprint reading to accurately measure where the
conduits are placed under the building.
a house, you may have to run one piece of conduit
to provide access for the power to an island in the
kitchen. In a commercial building, multiple runs of
conduit may be laid to later provide power for receptacles,
sub-panels and equipment.
electricians may dig the ditch with a back-hoe,
a trencher or the old-fashioned way - with a shovel.
The next step is the "rough-in".