Insulation requirements are flame retardant, and Lombok in the market mix, testing is simple, take a lighter to burn burn, remove the flame of the fire went out.
Especially for materials engineering, if you two insulated pipes should be installed in the wire and put it all in a casing, the entire House can save a lot of material. But too many wires within the casing, first use of high-power electrical appliances generate heat may burn out wires and insulated coat, there are security risks, followed by the wiring in the casing is too crowded, if needed maintenance could not draw out of wire.
Wire and conduit are too crowded, circuit process, buried in-wall wiring is wear on the insulation tube. This point many owners know, but each tube to wear wires, building owners may not necessarily clear.
High power is green, general lighting and sockets are separate, easy to control maintenance, their diameter is not the same, 1.5 General lighting, Socket 2.5. But sometimes very far away needs a small tile of wall next to the socket class lighting, taking also acceptable from this socket, you can save costs and simplify lines.