November 14, 2024

Electrical Re-Wiring of Homes in New Zealand

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Rewiring A House : A full breakdown

Rewiring a home is one of the most important upgrades a homeowner can make, especially if your home was built prior to 1970. With all of the appliances that we now use daily, Modern households have a much higher electricity demand now than we did in the late 1900s. If your older home contains original cabling, those wires are slowly degrading AND being placed under higher and higher electrical loading. This is a recipe for disaster, your risk of fire and electric shock is increasing every day. In New Zealand, rewiring is often necessary to bring older homes up to modern standard, to ensure you home is safe.

Types of Old Cabling : Old wiring in your house

There are different types of outdated wiring, such as

  • Vulcanised India Rubber (VIR) Cloth-covered wiring:
    • This was the original cabling system used when electricity was first introduced in NZ homes, having widespread use in the early 1900’s until around the 1940’s.
    • The cables are typically run within steel conduit or wooden channel duct through the walls and ceiling voids.
    • This style of cabling is commonly found in older bungalows and villas.
      (think Mt. Eden, Mt Albert etc)
    • Even though it’s the oldest type of cabling, it’s surprisingly safer than some of the cabling that was installed later in the 1900’s, as the insulation is held together by the cloth outer sheath.
    • However it’s definitely NOT safe to continue to keep in-use.
    • The internal insulation gets very brittle over time, and will fall apart easily especially when the cabling is disturbed (insulation cracking and degradation)
  • Tough Rubber Sheathed (TRS) wiring: This type of wiring was also popular during the mid-20th century (1940 – 1960)
    • The insulation on TRS cabling was found to quickly degrade over time
      (when removing we’ll often find that it just breaks apart in our hands)
    • Unfortunately the method of installation for this product was to install it bare against timber, (not run inside any protective covering), making it a particularly high shock and fire risk.
  • PolyVinyl Chloride Cable (PVC) wiring: This was used for a brief period in the late 1950’s / early  1960’s.
    • This cabling looks similar to modern cabling, however it contains a bare earth (no green internal sheathing).
    • It is much safer than TRS or VIR cabling, however it’s still prone to degradation
      We’ll often see a viscous sticky green fluid emitting from the ends of this cabling (which is super hard to get off your hands!)
  • Modern TPS (Tough Plastic Sheath) wiring: This is the modern standard, and has been in place since the early 1960’s. It’s a flat cable with a white outer sheath and coloured internal cores.
    • TPS is very robust – it will last decades without degradation when installed in normal conditions.
    • Issues with TPS:
      • TPS can become brittle when installed in cold environments (coolstores etc)
      • The only other issue we’ll find with TPS is that for homes built 1960’s-1990’s there is a chance that the TPS used for lighting circuits will have only 2 cores (no earth core)
      • The standard lighting at the time of installation (batten holders) did not require an earth.
      • This can make things difficult when replacing lighting with modern units, as the majority of new lights require an earth (especially any metallic lights).
      • In  these cases rewiring of the lighting circuits may be required.

Do I need to Rewire my house?

If your home was built prior to 1970 and has not had any major electrical work carried out, Then YES you are likely overdue a home rewire. Not sure if your home has been re-wired?

Get in touch with our team, we’ll book a site assessment where we’ll be able to quickly determine whether or not your home has been previously rewired. If you are found to be overdue a rewire, we will be able to price a cost-effective solution at the same time.

When should you Rewire your home?

If your home contains old cabling – the answer is ASAP. The more time passes, the greater the risk of fire and electric shock. Frequent circuit breakers tripping or blown fuses is a good indicator

The below are also good indicators, but are much more urgent: If you're experiencing any of these issues, turn power off and get in touch with us immediately:

  • Flickering lights, crackling light switches and/or intermittent power.
  • Warm or discoloured outlets and switches
  • A burning smell near electrical outlets or equipment.‍

How long does it take to Rewire a house?

The duration of a rewire job depends on the size and complexity of your home. For a typical residential rewiring, it can take anywhere from 2 to 5 days. We work efficiently to minimize disruption, often completing the rewiring of a 3-bedroom home in a single day if necessary.

"Worried about outdated wiring? Our expert electricians in Auckland provide safe, up-to-code rewiring solutions for both homes and commercial buildings, ensuring modern safety standards and efficiency."

How much does it cost to Rewire a house?

The big question!

There’s a significant amount of work involved in rewiring a home, so it’s no cheap exercise.

The total cost depends on the age, size, construction style and existing wiring type of the home.

The lowest cost rewire which we have completed was just under $10,000 (small home, easy access in ceiling void and underfloor, not many circuits)

The typical cost for a standard home is between $15000-20,000

Many clients will often re-wire at the same time as completing other renovations, as one big reno. This can lower the total renovation cost a little overall, as it’s easier to run cabling when walls are off, and wall /ceiling repair is lower cost if you’ve already commissioned a painter/plasterer for larger work.‍

Can I rewire a house while still living in it?

Yes- definitely, however you will likely have a few nights where not all power outlets will be working and some lighting circuits will be off.

We typically run extension leads and multi boxes to critical electrical equipment (Internet routers, fridges/freezers - and of course Xboxes) so that these can be used overnight.

We clean up any mess made and make sure that the installation is safe prior to leaving site each day.

NOTE: The kitchen appliances will likely be off during re-wire
So it’s a good excuse to order your favourite takeaways or to visit that new restaurant you’ve been eyeing up.

What’s involved in Rewiring?

A side from the obvious - all old cabling is replaced with new – we typically complete the following as well:

  • Replacing old sockets, light switches, and electrical fittings with modern ones.
  • Upgrading lighting to modern LED
  • Updating the fuse board / switchboard, including meterre location.
  • Adding RCD protection (electric shock protection)
  • Installation of a new earthing system
  • Upgrading the mains cabling if required, including the point of entry (for overhead supplies)

Types of wiring used today

Modern rewiring jobs in New Zealand homes use Thermoplastic Sheathed (TPS) cable, which is much safer and more durable than older wiring types. TPS wiring comes in various sizes and is designed to handle the electrical load of modern appliances, ensuring both safety and efficiency.

The benefits of Rewiring your home

  1. Increased Safety: New wiring significantly reduces the risk of electrical fires and electrocution.
  2. Improved Energy Efficiency: Upgrading to LED light fittings will reduce power consumption
  3. Compliance with Regulations: Rewiring ensures that your home meets the latest New Zealand electrical codes and standards, which are critical for safety and  insurance purposes​
  4. Increased Resale Value: Building inspectors and most clued-up home purchasers will be looking at the electrical system to see what state it’s in.
    • Having a full complaint, certified and modern electrical system increases the home’s value significantly, and widens the pool of prospective purchasers (some buyer’s will automatically fall off if they realise significant work is required)‍
  5. ‍Increased Capacity: A modern system allows you to safely add additional electrical equipment to the circuit.
        Things like:
    • Installing a high-power outlet for a welder in the garage
    • Installing a new EV charger fast charger
    • Adding power outlets
    • Adding solar systems and batteries

All become much more cost-effective and safer with a modern electrical system installed.

Can I Rewire a house myself?

Short answer: No,

Although it’s technically possible if you are the homeowner, the certification process is a nightmare and there are not many electrical inspectors who will sign this type of work off.

Also If you complete the installation incorrectly (there is a high-chance you will) there will be costs involved for rectification, rework and recertification.

We’ve had jobs we’ve been asked to inspect for certification in the past, we’ve ended up finding a litany of problems during inspection, which cost thousands to rectify.

The re-wiring costs in these cases have meant the total project cost blows out to double what they would have paid to get it completed by a professionally from the start.

Our advice:

You wouldn’t try to save money by doing your own dental work, would you?

The same applies here.

There’s a reason why it takes electrical workers a long time to get qualified, To do the job safely requires a lot of knowledge and experience. Leave the dentistry and the electrical work to the professionals.

Conclusion: Prioritizing electrical safety

Rewiring your home is an investment in both safety, comfort and longevity of your home. Whether your home shows clear signs of needing a rewiring or you’re simply preparing for future renovations, consulting a professional electrician will ensure the job is done safely and efficiently.

Don't wait for an accident to occur – if you think your home is overdue a rewire, act now!

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