How do I upgrade the electrical load of a landed home?

Landed electrical load upgrade: the steps

SP Group's FAQ on supply connection for landed homes sets out the order of work. Most of the paperwork sits with your LEW. Your part is choosing one, paying the charge and being reachable for the turn-on.

1. Engage a Licensed Electrical Worker. The LEW works out the load you plan to run and applies to SP Group for you.
2. Pay the connection charge. SP sets it as a standard charge based on the capacity applied for.
3. Work with the project officer. SP assigns one after payment.
4. Wait for permissions and cabling. Any agency approvals for the cable route come first, then the cable is laid to your gate pillar.
5. Book inspection and turn-on. Your LEW applies once the cable reaches the gate pillar.

The Energy Market Authority (EMA) says electrical work at home, including installing, repairing or modifying wiring, should be carried out or supervised by a Licensed Electrical Worker. For comparison, EMA says electrical work in an HDB flat needs a Licensed Electrician, the class of LEW approved for loads of up to 45kVA. For a landed house, ask each LEW you approach which load their licence covers before they quote. You can shortlist firms from the electrician pages in the directory.

Single-phase or three-phase

SP Group's guide to applying for electricity connection lists 230V single-phase supply at up to 23kVA, 100A. Larger loads are supplied at 400V three-phase. Your LEW checks your plans against that line first.

Whether you end up with a three phase landed house comes down to the load list. Picture a corner terrace being rebuilt with five bedrooms: a condenser for each aircon system, an electric vehicle (EV) charger in the porch, an induction hob and a pool pump. Your LEW adds up what could run at the same time and tells you which side of 23kVA you fall on.

For background on phases before you meet an LEW, read our three-phase power FAQ.

What SP Group does

Once your LEW submits the application, the SP Group supply upgrade moves to SP's side. SP's FAQ for landed residential premises says the connection charge is a standard charge based on the capacity applied for, under its Transmission Service Rate Schedule. You pay through the SP portal, the SP app or a kiosk, and a project officer is assigned after payment.

Cable work outside the home may need permissions from agencies such as the Land Transport Authority (LTA), PUB and the National Parks Board (NParks). SP says these take about three weeks, and cable installation about another three weeks. When the cable reaches your gate pillar, your LEW applies for inspection and turn-on, which is booked 10 calendar days ahead. The first inspection is free; a re-inspection carries a fee.

Not sure where SP's role ends and the LEW's begins? Our guide on what work needs an LEW covers the licensed side of the job.

Inside the house: DB and wiring

SP's work ends at the gate pillar, where its handbook says landed meters and service cables sit in a weatherproof compartment. Everything beyond that is your side. A bigger supply often means a new distribution board (DB) and new circuits, because the old board was sized for the original load. Added aircons or an EV charger may also need circuits of their own.

Since EMA says modifying wiring at home should be carried out or supervised by a Licensed Electrical Worker, ask whether the LEW handling the SP application will also plan the internal work. Keep the DB box and meter compartment closed. Checking ratings and wiring is the LEW's job.

Quotes for the internal side depend on the job. Our page on DB box replacement explains what the work involves and lists companies with their published prices.

Signs you have outgrown your supply

The clearest sign is a main switch that trips when heavy loads run together, such as an EV charger working through the evening while three or four aircons are on. Another is a renovation plan that adds rooms, an extra aircon system or a second charger to a supply sized for a smaller household.

Flats go through a different process. If a friend in a flat compares notes with you, see HDB electrical load upgrading for how it works there.

Planning with renovation

The neatest moment for an upgrade is during additions and alterations (A&A) works. The house is already a work site, and the new DB position can be agreed along with the layout. Bring your LEW in at the design stage so the load is settled before the electrical drawings are, and fit the SP timings above into the overall programme.

For wider questions about owning a terrace, semi-detached house or bungalow, see the landed homes FAQ.

Questions