152 Chapter 6
The engineer draws in the circuiting for every power receptacle. The circuit tie to the electrical panel
is noted. A legend provides a description for each symbol used on the plan. Conduit size, special power
specifications, and notes are included. A project with special equipment or systems requires additional
legends, wiring schedules, or diagrams.
Electrical systems provide power for lighting, outlets, and equipment. The local power company sup-
plies electricity to the building, including the meter. A licensed electrician can install an electrical panel
of the appropriate type and size.
Circuit breakers in the panel trip off if a circuit is overloaded. It is often an indication that there is a
problem with an appliance or other equipment or that too many items are plugged into one outlet source.
Outlets in wet areas must be grounded. Ground-fault-interrupter (GFI) outlets are required in bathrooms,
kitchens, or outdoor areas.
Special power outlets, called dedicated circuits, are placed on their own circuit. They are used for
sensitive equipment such as computers or equipment that requires voltage greater than 120 volts, in-
cluding outlets for electric ranges, large copy machines, or other special equipment.
An electrical engineer designs the system for a commercial or large residential project. An electrical
contractor can design the system for smaller residential projects. The drawings are part of the package
for pricing the project for the client and are used for construction. The electrician must wire all outlets,
lights, and panels according to the approved drawings.
The National Fire Protection Association publishes the National Electrical Code, which specifies the
design of safe electrical systems. Electrical engineers and electricians should know this code, as it is an
accepted standard for electrical installations. They should also be familiar with any state or local codes
that apply.
Reflected Ceiling Plan.
A reflected ceiling plan (RCP) is a drawing of a room or space looking down at the interior ceiling. The
designer or architect produces this plan to graphically show the ceiling treatment, ceiling grid, and the
placement of all light fixtures as well as light fixtures to be relocated or removed. The plan indicates the
type of ceiling (acoustical tile, gypsum board, etc) and the ceiling heights. The location of all light fixtures,
speakers, special lighting, ceiling outlets, and switch locations is indicated and labeled. A ceiling-fixture
legend is also normally included to provide a description for each symbol.
The engineer creates the electrical drawing for the RCP. It is an engineering drawing separate from
the architectural set. The engineer prepares his/her own drawings based on floor and reflected ceiling
plans provided by the interior designer or architect. The plans indicate to the engineer the location of
light fixtures, special ceiling features, toilet rooms, and any equipment requiring special venting.
The engineer’s drawing shows the circuiting and switching for each item on the ceiling. The circuit
connection to the panel is labeled. Conduit size when required, legends, and general and/ or specific
notes are provided on this drawing.
The RCP is basically a view of the ceiling from above. It is as if you were floating above the ceiling
and looking down at it (Figure 6.22). This view will show the location of light fixtures, drywall or T-bar
ceiling patterns, and any items that may be suspended from the ceiling. Figure 6.22 also shows a light-
ing layout plan.
Many projects will require electrical and mechanical drawings. The interior designer or architect will
provide the electrical and/or mechanical engineer with their reflected-ceiling-plan design. The engineer
will add the required information.