Introduction
Re-wiring a home can be an intimidating task, especially if you don't have experience working with electrical systems. Many homeowners think that re-wiring must be left to professional electricians, often at great expense. However, with proper planning and safety precautions, re-wiring a home is totally doable for the ambitious DIYer. I recently re-wired my entire house on my own, without any prior electrical experience, and saved over $5,000 in the process. In this comprehensive guide, I'll walk you through everything you need to know to safely re-wire your home and avoid hiring an expensive electrician.
Safety First - Dangers of Working With Electricity
Before diving into a home re-wiring project, it's absolutely essential that you understand the dangers and take every precaution to avoid injury or damage. Electricity is incredibly powerful and can easily kill or severely injure those who aren't careful.
Here are some key safety tips:
- Always turn off power at the main breaker before working on any electrical wiring. Lock out the breaker with a padlock so it can't accidentally be turned back on.
- Test wires and circuits with a non-contact voltage tester to confirm the power is off.
- Wear rubber-soled shoes and insulated gloves for shock protection.
- Keep a fire extinguisher nearby in case of electrical fire.
- Inspect all wiring connections carefully to ensure proper contact and insulation. Loose connections can cause arcing and fires.
- If you're unsure about any aspect of the re-wiring, consult a professional electrician or inspector to review your work. It's better to be safe than sorry when electricity is involved.
Follow these best practices and you can safely take on a re-wiring project without risking life or property.
Gather Necessary Materials and Tools
To re-wire a house, you'll need an assortment of basic electrical supplies:
- Romex NM-B Wire - The most common household wire, available in various sizes. Choose gauge appropriate for your home's electrical load.
- Wire strippers - For stripping insulation off wires.
- Voltage tester - To safely check if wires are live.
- Wire nuts - For connecting wires together.
- Electrical tape - For insulating connections.
- Cable staples - To affix wiring to studs and joists.
- Junction boxes - For housing wire connections.
- Circuit breakers - For shutting off and protecting circuits.
- Conduit and tubing - For protecting exposed wire runs.
You'll also need standard hand tools - hammer, screwdrivers, pliers, etc.
Purchase quality materials from electrical supply stores. Don't risk your safety trying to save a few bucks on questionable bargain tools or wire.
Planning the New Wiring Layout
Carefully planning the layout for the re-wired electrical system is crucial. Consider the placement of:
- The main service panel
- Circuit breaker boxes
- Individual outlet and switch boxes
- Appliance connections like stoves, heaters, etc.
- Lighting fixtures
- Low voltage wiring (phone, internet, video)
Create a detailed floor plan mapping out the entire circuit layout. Indicate wire runs, junction points, breaker assignments, and fixtures. Planning ahead will make the physical re-wiring work much simpler.
When planning, make sure to:
- Distribute electrical loads evenly across circuits.
- Use the shortest wire runs possible.
- Allow space for expanding wiring in the future if needed.
If re-wiring due to aging/insufficient electrical service, this is also an ideal time to upgrade to 200 amp service to support additional capacity.
Running and Securing New Wiring
With safety gear on and power off, you're ready to start running the new NM electrical wiring throughout the house.
Here are some tips for smooth and safe wiring:
- Carefully measure wires runs and cut wires with a few extra inches for flexibility in connections.
- Neatly secure cables to framing studs using cable staples. Keep staples spaced 12-16 inches apart.
- Drill holes in framing members for routing wires between rooms. Avoid notching/boring holes in joists which could weaken them.
- Run cables along the edges of rooms for a less visible install. Feed down walls to receptacles.
- Junction boxes are required anytime you have a splice, connection, or switch. Mount securely.
- Label both ends of each wire with circuit number for easy identification.
Take it slowly and methodically. Don't rush the critical wiring work. Do it right the first time.
Installing New Breaker Box and Breakers
The home's main breaker box distributes power from the service line to all your home's circuits. With re-wiring, it's a good idea to replace the breaker box too, especially if the existing one is outdated or insufficient.
Follow these steps for breaker box installation:
- Choose a location close to the service entry point if possible. Garages or laundry rooms are ideal.
- Mount the new breaker box securely to the wall framing using proper screws.
- Feed the service line wires into the box and attach to the main lugs or bus bar.
- Add new breakers one at a time following the floor plan, labeling each circuit clearly.
- Ensure breaker amp ratings match the wire gauge of the circuits. Don't overload.
- Include spare spaces for adding breakers later if needed.
Consult the breaker box manufacturer instructions for proper mounting and connection. Call the utility company to switch power back on once you've verified all connections.
Testing and Troubleshooting Your Work
With all new wires run and connected, it's time to test each circuit:
- Turn the main power back on, but leave all breakers off initially.
- Flip each breaker on one at a time and test the outlets, switches, and fixtures on that circuit.
- Check for proper function of lights, receptacles, and appliances.
- Use a voltmeter to verify correct voltage at outlets (120v).
- Inspect for hot spots or scorched wires indicating connections issues.
- If any circuit fails to work properly, check all connections and splices on that run.
Don't assume everything was done correctly. Thoroughly test each circuit before completing the re-wiring project. Catching any issues now is much easier than troubleshooting later. Call an electrician if you need help diagnosing any circuit problems.
Wrapping Up the Project
Once all circuits are working properly, you're almost finished:
- Replace any opened walls damaged during wiring - drywall, insulation, etc.
- Install wall plates and covers on all junction boxes and fixtures. No exposed splices.
- Label all circuits clearly in the breaker box so future issues can be diagnosed easily.
- Check that all lighting fixtures, switches, and receptacles work as intended.
- Consult your local building codes department to have the completed work officially inspected if required.
Take photos at each step of the process. This professional-grade re-wiring will add functionality and value to your home for decades to come. And you saved thousands by safely doing the work yourself. Congratulations on a job well done!