Electrical, Plumbing and Drainage Layouts

Electrical, Plumbing and Drainage Layouts

A Grade 12 civil set includes the services: the systems that make a building usable. Each is drawn on its own layer or sheet over the same floor plan, so one system can be read without the others.

Electrical layout. Symbols for light points, switches, socket outlets and the distribution board, with lines showing which switch controls which light. Those lines indicate control, not the physical cable route.

Plumbing layout. Hot and cold supply runs to each fixture, isolating valves and the geyser position.

Drainage layout. Waste pipes from each fixture to the gullies and inspection eyes, then to the sewer connection. Drainage must fall toward the sewer — a gradient is essential, commonly 1:40 for 110 mm pipe, and it is stated on the drawing.

Worked example. A drainage run drawn level looks tidy but cannot work: waste moves by gravity, so without a stated fall the pipe blocks. The gradient is a functional requirement, not an annotation.

Core checkpoint: Services go on separate layers over a common plan. Each must be readable alone, and they must not clash with one another.