Residential · Safety
Rewiring an Old House in Malaysia: Warning Signs, Cost and What the Job Involves
Electrical faults are the leading cause of house fires in Malaysia. The Fire and Rescue Department (JBPM) attributes about 60 per cent of house fires to electrical issues (Bernama, 3 August 2025), and recorded 1,690 residential fires in 2025, more than half of them in terrace houses (The Star, 6 March 2026). Old wiring is one of the main reasons. This guide explains how to tell when your home needs rewiring and what is involved.
Warning signs your wiring needs attention
| Sign | Why it matters |
|---|---|
| The house is 25–30+ years old with original wiring | PVC insulation hardens and cracks with age and heat |
| Ceramic fuses or no RCCB in the DB | No earth-leakage protection against shock or fire |
| Sockets or switches feel warm, look brown or melted | Loose or overloaded connections are overheating |
| Breakers or the RCCB trip often | Leakage or overload somewhere on the circuit |
| Burning smell, buzzing or crackling | Arcing inside a socket, switch or junction box. Switch off and call an electrician |
| Lights flicker or dim when appliances start | Undersized or loose cabling |
| Two-pin sockets or no earth wire | Older installations may lack proper earthing |
| Many extension cords and adaptors | Not enough sockets for modern needs, a common fire cause |
JBPM's Director-General has advised homeowners to have their wiring inspected by a qualified electrician every 10 to 15 years, particularly older homes and newly completed ones (RTM, 3 Ogos 2025).
Full or partial rewiring?
- Inspection first. A registered contractor tests insulation resistance, earth continuity and the RCD, then tells you which circuits are safe.
- Partial rewiring replaces only failing circuits, often the kitchen, bathrooms or socket circuits, plus a new DB. This suits homes where some circuits test well.
- Full rewiring replaces all cables, accessories and the DB. This is recommended for very old installations, fire-damaged homes or major renovations.
How much does rewiring cost?
Published estimates from Malaysian sources (not Luco Group prices):
| Property | Full rewiring estimate | Source |
|---|---|---|
| Single-storey terrace | RM5,000 – RM10,000 | WiringRumah.my |
| Double-storey terrace | RM8,000 – RM15,000 | WiringRumah.my |
| Condo, full unit | RM3,000 – RM6,000 | PropCashflow |
The cost depends mainly on the number of points, concealed versus surface wiring, the length of cable runs and the condition of the walls. To estimate yours from Luco Group's fixed per-point prices (light RM135, fan RM155, socket RM175, aircond RM225, water heater RM330, all-in up to 8 metres), use our home wiring calculator, then add a new DB from RM1,180 (12-way) as shown in DB box replacement.
Tests your contractor must carry out
Section 11.2 of ST's domestic wiring guideline lists the tests required before a new or rewired installation is energised:
| Test | Requirement |
|---|---|
| Continuity of protective conductors | Below 1 Ω |
| Insulation resistance (500 V DC) | At least 1.0 MΩ |
| Polarity | Correct for every switch and socket |
| Earth electrode resistance | Below 200 Ω with RCD protection; below 10 Ω with a lightning protection system |
| RCD operation | No trip at 50% of rating; trip within 200 ms at 100%; within 40 ms at fast trip |
| Earth fault loop impedance | Measured |
The results go on Borang H, and the contractor issues Borang G for supervision and completion. Ask for both. Source: ST GP/ST/No.39/2024, section 11.2.
How the job is done
- Survey and tests of the existing installation.
- Plan circuits and points room by room, adding sockets and dedicated circuits for aircond, water heater, kitchen and future EV charging.
- Install the new DB with RCCBs and RCBOs that meet Regulation 36.
- Run new cables in conduit (concealed) or casing (surface), following the ST cable sizes: 1.5 mm² for lighting, 2.5 mm² for sockets, 4–6 mm² for heavy appliances.
- Replace all accessories with ST-SIRIM labelled switches and sockets.
- Test, certify and hand over Borang G and H, with the circuit chart labelled in the DB.
A condo usually takes 2 to 4 days; a double-storey terrace about 1 to 2 weeks, longer if walls are hacked and replastered.
Plan rewiring with your renovation
Rewiring is cheapest before plastering, painting, ceiling boards and kitchen cabinets go in. If you are renovating, bring the electrician in at the planning stage so conduits are laid once.
Frequently asked questions
How long does house wiring last? Well-installed PVC wiring can last decades, but heat, overloading and poor connections shorten its life. Have it tested every 10 to 15 years, as JBPM advises.
Can I stay in the house during rewiring? In most cases yes, with power off in parts of the house during working hours. Full rewiring with hacking is easier if the house is empty.
Do I need TNB approval to rewire? No, unless you are increasing the supply, for example upgrading to three-phase.
Will rewiring reduce my electricity bill? Not directly, but it removes leakage and overheating faults that waste energy. See why your TNB bill went up.
Sources
- Bernama, JBPM attributes 60 pct of house fires to electrical issues, 3 August 2025. bernama.com
- RTM Berita, Peralatan elektrik, punca 60% kes kebakaran rumah, 3 Ogos 2025. berita.rtm.gov.my
- The Star, When homes become fire hazards, 6 March 2026. thestar.com.my
- Suruhanjaya Tenaga, GP/ST/No.39/2024, sections 8 and 11.2. st.gov.my PDF
- WiringRumah.my, Old house rewiring cost in Malaysia 2026. wiringrumah.my
- PropCashflow, Renovation costs Malaysia. propcashflow.my
This guide is general information, not a substitute for an inspection by a registered electrical contractor. Regulations and TNB charges change; always check the linked official sources.