Types of Electrical Wiring Used in Singapore

On site, "cable" covers everything from a 1 mm² lighting flex to a 95 mm² busbar tap-off. Knowing the working categories helps you read a scope of works.

Single-core PVC (the workhorse)

PVC-insulated single-core conductors pulled into PVC or metallic conduit and trunking. Standard for residential and most commercial scopes. Sized in mm² — 1.5 mm² for lighting, 2.5 mm² for sockets, 4 mm² and 6 mm² for water heater and AC, 10 mm² and up for sub-mains.

Multi-core flexible (where movement happens)

Multi-core sheathed flexibles for appliance connections, plug tops, lighting drops and pendant fittings. Available in 0.75 mm², 1 mm², 1.5 mm² and 2.5 mm² typical sizes. Not for fixed wiring in walls.

Armoured (SWA) cable

Steel-wire-armoured cable for external runs, sub-mains between buildings on a landed plot, and any feeder where mechanical protection matters. The armour also serves as the CPC if correctly terminated.

Fire-rated (FR / FP) cable

Mineral-insulated or specifically rated cables for fire-alarm, emergency lighting and life-safety circuits. Required where SCDF requirements specify circuit integrity under fire conditions. Always specified on commercial fit-outs by the M&E consultant.

LSZH (Low-Smoke Zero-Halogen)

Cables with a low-smoke, halogen-free outer sheath, used in transit, hospital and high-occupancy commercial spaces where evacuation visibility matters. Often specified for tenant fit-outs by the landlord fit-out manual.

Selecting the right cable for the job

• Match conductor size to the protective device — undersized cable is the most common amateur error
• Match insulation to the environment — heat, UV, oil exposure all degrade PVC
• Match termination to the cable — bi-metallic terminals for any aluminium-to-copper joint
• Match colour code to the SS 638 conventions — brown live, blue neutral, green/yellow earth