Dear John: This is a question we get frequently. The answer, as it is so often with major home projects, is there’s a big potential cost range for rewiring a house.

You can expect to pay $8,000 to $15,000 to rewire a 1,500- to 3,000-square-foot home. The precise cost will depend on the size and age of your house, the ease with which an electrician can access old wiring, and the quirks that abound in older homes.

Is rewiring a house necessary?

How can you be sure your home requires rewiring? With something as important, and potentially dangerous, as the system that delivers your home’s electric power, it’s crucial to rely on expert advice.

Here’s what electricians who’ve earned top ratings from Angie’s List members tell us:

If your home is 50 or more years old, you should at least consider having your wiring inspected by an experienced pro, as it may feature dated knob-and-tube or aluminum wiring components. You should be particularly concerned if you notice any of these signs:

• Frequently tripped circuit breakers or blown fuses
• A persistent burning smell, sometimes accompanied by a sizzling sound
• Charred or discolored outlets and switches

Fortunately for homeowners, rewiring is typically a once-in-a-generation home expense. But considering the risks of improper or outdated wiring, it’s an upgrade you might not want to put off. In 2014 (the most recent year data is available), the U.S. Fire Administration attributed 23,900 residential fires to electrical malfunction.

How do you rewire a home?

Rewiring involves removing as much of the old wire as possible and installing modern, so-called non-metallic wire. Compared to older wiring types, non-metallic is safer, easier to work with and doesn’t get hot when surrounded by insulation.

One option for removing old wiring is to tear out walls, run new wires and seal everything behind new drywall. That, however, is expensive and time-consuming. A job may land on the low end of the cost range if walls need few cuts and wiring can run through a basement, crawlspace, floor joists and attic.

To preserve an older home’s integrity, electricians often fish wires through walls, using rods and a thin metal line called fish tape. This method occasionally requires a small cut and patch, but preserves plaster walls while adding the conveniences of modern wiring.

In the process of rewiring, whether removing knob and tube wiring or simply updating, an electrician will almost always upgrade your service capacity. Homes with old wiring may have 60 to 100 amps of service instead of today’s standard minimum of 200 amps.


472 Maitai Valley Road Nelson 7010 NZ