SIRIM cable, "JKR" cable and cable sizes for Malaysian homes

“Pakai wayar SIRIM ke?” is one of the first questions Malaysian homeowners learn to ask a wireman, and one of the most misunderstood. Here’s what it means. House wiring cable is regulated equipment: it has to be approved and carry the SIRIM certification mark printed on the cable itself. Plenty of brands carry that mark, from budget ones to the well-known names, so “SIRIM” doesn’t mean a particular brand. When electricians say “JKR cable”, they mean brands from makers on the Public Works Department’s approved list, which many electricians regard as a step up in quality and price. Our house wiring cable page covers the cable types, colours and brands in more detail.

What the rules say

The Energy Commission’s Guidelines for the Approval of Electrical Equipment list non-armoured PVC wire and cable from 0.5mm² to 35mm² as regulated equipment, covering the ordinary single-core cable used in house wiring. Regulated equipment has to be approved by ST and marked. For small items such as cable, the guideline says the SIRIM Certification Mark is marked on the product rather than with a sticker on the packaging. ST’s domestic wiring guideline adds that house wiring cable must be copper and must carry the ST-SIRIM label printed on the insulation.

In practice that’s printing along the insulation: the SIRIM mark and certificate details, the standard, the size and the manufacturer. One electrician pointed out that unapproved cable often has printing too, just without the SIRIM mark, so look for the mark itself rather than any text.

You can also check the approval yourself. ST’s public listing of approved equipment has a separate approval number for each brand and size. Choose the category “WIRE / CABLE / CORD (non-armoured) 0.5mm to 35mm” and type the brand. In October 2026, 64 brands had single-core house-wire approvals there.

“SIRIM” versus “JKR” cable

Cable is normally sold in 100-metre coils, although many budget listings are for 80- or 90-metre rolls, so compare the price per metre. Sellers and wiremen use two informal tiers:

• “SIRIM” cable: any SIRIM-marked brand, including budget ones such as Cablelink. One Puchong cable seller advertised brands such as Million, MPC, Arus Jaya, KTK, Bluetech, Plus, Itoku and PIPC in January 2026 at RM55 (1.5mm²), RM88 (2.5mm²) and RM140 (4mm²) a coil, saying this was cheaper than shops. Other 2026 posts put typical SIRIM 2.5mm² at RM103–120.
• “JKR” cable: brands from JKR-approved makers. The same seller listed Mega, Tonn, Multi Wire and Ta Tun and priced them at RM85, RM128 and RM220. Southern Cable is another JKR-listed maker electricians name; our pages on Mega Kabel and Tonn Cable cover those two. Elsewhere, Mega 1.5mm² was quoted at RM78–107 and Mega 2.5mm² at about RM140–180. Depending on the seller, the “JKR” brands cost roughly 30–60% more.

Marketplace prices for a single roll run higher than these wiremen’s prices. In October 2026, the median online price of a 2.5mm² roll was about RM230 for Mega and RM165 for Cablelink. At stores selling several brands, Mega, Southern and Tonn were priced within a few ringgit of each other, and a Cablelink roll about 30% lower (19–44% across sizes), though some budget rolls are shorter than 100m. The product pages linked above list the stores.

JKR’s approved list for PVC insulated cable, checked in October 2026, names 22 makers, all manufacturing in Malaysia. They include Mega Kabel, Tonn Cable, Southern Cable, Tai Sin, Utama, Olympic, Multi Wire, Ta Tun, Central Cables, Sama, Smart, United MS Cables, Magnum, Fuji, Yogawa and DNF. The listing covers PVC cable generally, armoured and non-armoured. JKR status isn’t printed on the cable, so check the brand against the list if it matters to you.

Electricians disagree about how much the tiers differ in practice. Some say ordinary SIRIM cable is perfectly adequate, and you don’t need to pay for Mega just to have SIRIM cable. Others say SIRIM brands come in grades. In one thread, Itoku was called soft next to “JKR spec” Mega, Multi Wire or Southern, and one commenter said Cablelink 4mm² was only as thick as Mega 2.5mm². These are impressions rather than measurements. Both sides agree on the point that matters most: don’t use cable without the SIRIM mark.

Why electricians are wary of unmarked cable

The stories repeat across threads:

• a “4mm²” unmarked cable that turned out to have about 2.5mm² of copper inside thick insulation;
• conductors that aren’t pure copper;
• coils labelled 100 metres that measure closer to 80;
• one commenter’s account of unmarked neutral cable whose insulation turned white and crumbled within five years, forcing a rewire back to the DB.

Two simple checks help. House wire up to 10mm² is normally seven strands: 7 × 0.53mm for 1.5mm², 7 × 0.67mm for 2.5mm² and 7 × 0.85mm for 4mm², per Tonn Cable’s data sheet. And a 100m roll of 1.5mm² copper cable weighs about 2.1–2.3kg before packaging by the makers’ figures, 2.5mm² about 3.3–3.6kg. A light roll is short, thin or not copper.

One homeowner asked whether they could save money by using SIRIM cable for live and unmarked cable for neutral and earth. Nearly every reply said no. One of the two most-liked answers argued the neutral matters as much as the live; another reply pointed out that the neutral carries the same current as the live. The earth conductor is what lets fault protection work, so it isn’t the place to economise either.

Which size for which circuit

ST’s domestic wiring guideline sets minimum conductor sizes against breaker ratings, and electricians in these groups mostly follow it:

• 1.5mm² for lighting and fan circuits. ST’s example schematics put these on 6A breakers, and electricians commonly mention 10A. The MS 1979 code of practice doesn’t allow anything smaller for fixed wiring.
• 2.5mm² for general socket circuits: up to 20A as a radial circuit, or 30–32A as a ring circuit, per ST’s Table 6.3. A 32A radial socket circuit needs 4mm².
• Aircond: ST’s minimum-size table (Table 8.2) puts aircond, water-heater, cooker and pump circuits at 4–6mm², and its example schematics wire split units under 3HP with 4mm² on a 20A breaker. Some installers use 2.5mm² on 16–20A for small units, and contractors price the two separately. Check which you’re getting; one homeowner who paid RM1,400 for three aircond points found all three were 2.5mm².
• Water heaters: 4mm² minimum for any size under ST’s water-heater guideline, rising to 6mm² above 5,711W and 10mm² above 7,139W. See the water heater guide.
• Main cable to the DB: at least 10mm² for a main breaker up to 40A, 16mm² up to 63A and 25mm² up to 100A (Table 8.2).
• Continuous high loads: for an 18A commercial steamer pot running long sessions, most replies recommended 4mm² (or 6mm²) for margin, though some said 2.5mm² on a 20A breaker is within its rating.

The rule underneath all of these: the breaker must never be rated higher than the cable can carry for the way it’s installed. Electricians regularly flag 32A breakers on 2.5mm² radial circuits, a common mismatch. If you’re adding circuits, the house wiring prices guide shows how quotes separate 2.5mm² and 4mm² points.

What to ask for

• A quote that names the cable brand and size, not just “wayar”.
• SIRIM-marked cable for every conductor: live, neutral and earth.
• If you want JKR-listed cable, check the brand against JKR’s eMAL list and expect to pay noticeably more for the cable itself.
• A look at the coil or the printed cable before it goes into the conduit, so you can check the mark, and the brand’s approval in ST’s listing, yourself.