All About Electricians Daily

Rewiring or Rewire A Home

Feb 9

Replacing the wiring in an old house

Replacing electrical wiring makes an old house safer, more modern and livable. However, rewiring doesn't cover only houses. All buildings, factories and warehouses must be inspected regularly and rewired as needed. How you proceed will depend on your budget, access to the walls, attic and crawl space, and the amount of demolition allowed. This type of remodelling is easier to do in a newly purchased home than in an already occupied home. Do not attempt to replace your wiring unless you have experience in electrical construction.

When you buy a property, ask the seller or real estate agent if there is a "Certificate of Compliance for Electrical Work" that you can review. If so, you will be able to see precisely what electrical work and rewiring has and has not been done.



When is whole-house rewiring necessary?

When trying to figure out if your home needs to be rewired, the first thing to check is when it was built. If it was constructed in the 1980s or before, it's definitely worth hiring a licensed electrician to check the wiring. The reason is:

  • Modern wirings are safer and more durable.
  • The sheathing of old wiring deteriorates over time. This means that the wires may no longer be insulated.
  • In some old installation methods, the wires were installed on joists in roof cavities. This means that you or a worker who has to climb onto the roof could hit the wires or be electrocuted if worn.


How to replace; step by step process

Permits and regulations

Permission from the local building department is needed to rewire a home. Homeowners can make electrical repairs to their homes themselves, but the work must be inspected. You might wish to engage an electrician to assist you with your planning and exploration, as understanding how to wire an old structure requires a lot of experience and knowledge.


Access to the walls

The first step in replacing wire is determining how much access to the walls. If you bought a new house, you should cut numerous holes in the walls before painting or moving in to make it easier to run the new wiring. If your home is already occupied or you don't want to cause a major inconvenience, the work will take much longer, and your options will be limited. You may need to leave the wiring in the walls intact and only replace the cable in the attic or crawl space. 


Locations of the new cable

Most of the new cable will likely be run through the attic and crawl space before entering the walls. Where you run the wires will depend on whether you have access to the rooms, but generally, outlets will be run from the bottom and wiring for lighting will be run from the top. Be aware of hazards such as asbestos, fibreglass insulation and old wiring. Ensure the power is off before drilling new holes and cutting into walls.


Rewiring an electrical outlet

To replace the wiring of an outlet, the old outlet must be removed. You may be able to pull the old wire back through the hole where it runs. However, if it's stapled down, that's not an option. You will then need to drill a new hole for the new cable.


Drill new holes

If you're relocating an outlet or light switch and can't reuse the hole for the old cable, you'll need to drill a new hole. Although it takes some skill, new holes can be drilled using a flexible drill bit from space. Alternatively, you need to access the crawl space or attic and drill through the wood panel. To find the hole, you need to measure carefully. Drill a 1/8-inch hole first to make sure you won't drill a hole through the floor or into a stud.


Determine the number of circuits

Old wiring often doesn't provide enough circuits for the power needs of modern appliances, lighting and technology. So before you start laying cables, you need to plan your circuits according to the National Electrical Code of Australia. The National Electrical Code of Australia contains guidelines that must be followed, especially for rooms such as kitchens and bathrooms. Do some research on electrical circuits in the home to help guide your planning, or hire an electrician as a consultant.


Replacing the switchboard

In addition to replacing the wiring, you should also consider replacing the electrical service, including the main electrical panel and all subpanels. This may be necessary if your old electrical panel does not have enough space for the new circuits. This may also be advisable if your old panelboard is in poor condition or if you have fuses instead of circuit breakers. If you're upgrading the electrical panel, you'll probably also need to replace the wiring that supplies the house. Again, this is another job best left to a professional electrician.

Original article is here