A client asked me to create an electrical plan for her. I responded: “Oh, no problem. But first, I have to design a reflected ceiling plan.” She wondered what that entailed. I explained briefly and would like to elaborate.
Although not required for a simple permit submission, a reflected ceiling plan is a part of the overall architectural drawings set. It shows the lighting, sprinklers, smoke detectors, and any other objects that are located in or on the ceiling, such as the mechanical air diffusers and grilles.
It is referred to as a reflected ceiling plan because it is drawn as if it were reflected onto a mirror on the floor. This way the reflected ceiling plan has the same orientation as the floor plan associated with it (see below). Another way to understand how it works is to imagine the ceiling as a transparent plane you could see right through to the floor below.
To keep it less confusing, the items below a certain height are not shown at all. The doors, however, are an exception. Showing the doors & door swings with a dashed line ensures that the light switches are not placed behind the doors when they are opened.
In addition to a lighting layout, a reflected ceiling plan (RCP) should contain the following:
- The location of switches.
- The construction material of the ceiling (gypsum board, acoustical tile, etc.). In our case it’s Recycled Insolated Panels.
- A specification of finish (paint, stucco, etc.) of the ceiling material. In our case it’s white paint.
- The height of the ceiling above the finished floor (A.F.F.). In our case, the ceiling is sloped in two directions; any value would be an approximation and it might be misleading.
- A legend explaining the symbols on the RCP.
- An explanation of any ceiling features such as bulkheads, soffits, raised or vaulted areas, trim or decorative applications. We have a dropped ceiling in one of the closets (the one that is accessed from the existing house) for the purposes of achieving required insulation.
A reflected ceiling plan reveals the design intent. Wall sconces are placed above and are centered on window panels. Track lighting (I’m picturing low voltage fixtures on wire cables) is featured on the opposite wall. Nothing is actually attached to the recycled insulated panels.
A reflected ceiling plan shows wiring diagrammatically as a dashed line in order to help envision which light switch is associated with each light fixture. In fact, there’s much more to switching, but we’re not ready to make those decisions. We’re just getting organized, and this plan is a good place to start.