A breaker panel in the wall of a newly constructed home.

How To Update Electrical Wiring In An Old House

Carey Chesney6-minute read
April 21, 2022

An old home can be full of charm and wonder. Original wood floorboards, detailed molding, period specific touches that can ignite a conversation, the list goes on and on. Many home buyers prefer a house with a little history as opposed to a newer-built one.

The downside of buying an older house is you are more likely to spend some money on maintenance or updates. This is especially true when it comes to safety issues like an old electrical system.

Understanding how to update electrical wiring in an old house will help you assess, fix, and maintain this important part of your antique abode. Read on to learn all about this, including an answer to the question you are probably pondering right now: “How much does it cost to have a house rewired?”

Do I Need To Replace The Wiring In My Old House?

Before we get into how to update electrical wiring in your old house, let’s look at whether you need to. If you are a homeowner with a historic home, you may need to replace your outdated wiring system. If everything is working and up to code, you may not.

  • Is your wiring outdated or not up to code? Having up-to-date wiring that meets current wiring codes is critical for two key reasons. The first is safety. U.S. electrical codes created by the National Fire Protection Association (NFPA) and are intended to … you guessed it … prevent fires.

The second reason has to do with selling or renting your property. When you find a potential buyer or renter, an inspection needs to be done before you can seal the deal. This involves a licensed electrician reviewing all the wiring in your home to make sure it is up to code. If the electrician finds outdated wiring (which often happens in older homes) you might fail an inspection and not be able to sell or rent the home until new wiring is installed.

  • Do your systems use aluminum wiring? If the electrical system in your older home has aluminum wiring, it might be time for rewiring. Aluminum wiring presents a number of dangers such as loosening over time, overheating and causing fires.
  • Are your amps able to provide your home with enough power? Most older homes use a standard 60 amps or 100 amps, but modern homes require 200 amps. If your home doesn't have 200 amps, it might be time to call an electrician.
  • Do you frequently experience electrical problems? Many signs of the need for new wiring in an old home can be observed during daily life. Burning smells, discoloration of outlets and switches, flickering lights, frequent circuit breaker trips are a few of the signs homeowners can look out for.

Let a pro do it for you.

Find a top-rated pro to help on HomeAdvisor.

6 Steps To Update Wiring In An Old House

Now that you know the signs, let’s dive into the process for rewiring an old house. This consists of reviewing all of your electrical systems, understanding your local codes, making a list of your desired electrical projects, contacting a reputable electrician, planning for demolition and reconstruction, and finding hardware that matches your home.

1. Review All Of Your Electrical Systems

It’s important to make a list of what all of your electrical systems are as well as where and how you use them. Why? Well, you can’t tackle a project like rewiring an old house without knowing exactly what you are getting into. Here are some things you should be sure to cover.

  • Inspect your circuit breakers: Look for rust or signs of pest activity. Make sure all of the circuit breakers flip on and off easily and don’t get stuck.
  • Test your GFCI outlets: All outlets that are near a water source should be ground fault circuit interrupt (GFCI) protected. Press the test button to make sure all GFCI outlets are safe.
  • Test all other outlets: Buy a cube tester and plug it into each outlet in your home. A light will display that corresponds with specific wiring issues. Also check for outlet tightness. If it wiggles, that's bad. Be sure to do these tests on your outdoor outlets as well.
  • Look at all the wiring you can see: Look over any wiring you can see like in the basement or attic. Make sure there are no cracks or splits.
  • Test your voltage: If certain appliances are acting weird or lights are flickering, it might be a voltage issue. Check the power at each outlet with a voltmeter. For standard 120-volt outlets, you might see it indicate between 110 and 130 volts. That’s normal. If the volt readings are outside of this range, you have a problem to address.
  • Look at your extension cords: Make sure they are free of cracks or splits. Also make sure extension cords you are using for power tools have the correct amperage rating.

2. Understand Your Local Codes

It’s important to understand your local codes for electrical work such as how many outlets you can have in each room and what type of wire you need to use. This ensures a safe rewiring of your old house as well as passing any necessary inspections.

3. Make A List Of Desired Electrical Projects

Make a list of any projects you need completed prior to finding an electrician such as:

  • Upgrading the main service panel
  • Running wires directly from a circuit breaker to an outlet
  • Spacing outlets at 6 – 8 feet apart to avoid extensions
  • Installing three-prong outlets
  • Adding ground-fault circuit interrupters in the kitchen, bathrooms and outdoors

Electricians that you call for a quote need to know the scope of work before telling you how much it will cost. They also need this to determine when they can get the work done and how long it will take.

4. Contact A Reputable Electrician

Going the DIY route may seem like a good way to save money, but it’s best to hire a reputable electrician to complete your electrical rewiring for you. Electricians are highly trained to get work done safely and effectively. They are also trained to make sure that they protect your existing infrastructure. Consider searching for an electrician that understands older homes if one is available in your area.

5. Plan For Demolition And Reconstruction

Rewiring an old house is a major project, so it’s important to discuss demolition and reconstruction after the rewiring with your electrician or a contractor. Walls and floors might need to be removed, so it is going to be disruptive. You want to make sure you have a plan for returning things to normal after the rewiring by the electrician is complete.

6. Find Hardware That Matches Your Home

To complete the project, you’re going to want to match the current aesthetic of your older home’s natural beauty by matching the light switches and outlet covers with the design of your house. After all, why buy an older home full of character if you’re just going to put modern finishes in it, right?

Let a pro do it for you.

Find a top-rated pro to help on HomeAdvisor.

Rewiring An Old House: FAQs

Now that you have a basic understanding of how to update electrical wiring in an old house, let’s look at some frequently asked questions about this process.

How much does it cost to have a house rewired?

According to Thumbtack.com, the average cost of a house rewiring is $1,500 – $10,000 depending on several factors. The two most critical price indicators are the scope of the project and the electrician’s rates. If you are just having a few outlets converted to GFCI, the cost might be pretty minimal. If you are asking an electrician to replace wiring in an old house, like the entire house, that will be pricey.

Does rewiring an old house add value?

Absolutely. Rewiring an old house is an expensive investment, but it can help protect your home and increase your property value by increasing efficiency. You will be safer and save money on electrical bills while you live in the home and it will be more appealing to potential buyers when it’s time to sell.

How long does a house rewire take?

According to Thumbtack.com, rewiring a home takes an average of 3 – 10 days, but the length of time depends on the home's size, age and how extensive the project is. Rewiring a 900-square-foot home that is relatively new can be done in just a day or two. Rewiring an old house that is 3,500 square feet large is going to take considerably longer.

Can you rewire a house without removing drywall?

Even if you’re a DIY aficionado, it’s probably not a good idea. Rewiring can sometimes be completed without removing drywall or other extensive work, making the DIY approach seem doable. That said, talk to an experienced licensed electrician first to get a sense if the project is really something you want to try and take on yourself.

The Bottom Line

An old house can be full of wonder. Understanding how to care for it will ensure you can enjoy that feeling for years to come. Learning how to update electrical wiring in an old house is a critical part of this. Keep your eyes peeled, use the right tools, and hire the right people to make sure your experience rewiring an old house has the best outcome possible. Ready to learn more? Find more tips for homeowners in the Learning Center.

Let a pro do it for you.

Find a top-rated pro to help on HomeAdvisor.

Apply For A Mortgage Online

Carey Chesney

Carey Chesney brings a wealth of residential and commercial real estate experience to readers as a Realtor® and as a former Marketing Executive in the fields of Health Care, Finance and Wellness. Carey is based in Ann Arbor and attended the University of Wisconsin-Madison, where he majored in English, and Eastern Michigan University, where he recieved his Masters in Integrated Marketing & Communications.