Rewiring the electrical system in your home can be a daunting task, but with proper preparation and safety precautions, it is possible for a homeowner to do it themselves without hiring a professional electrician. Below I outline the complete process for how I successfully rewired the electrical system in my home to make it safer and more efficient.
Understanding Electrical Systems Basics
Before beginning any electrical project, it is critical to understand some basics about home electrical systems. This ensures you work safely and carry out the rewiring properly.
The Main Components
The main components of a residential electrical system include:
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Electrical panel/breaker box - This is the central hub where all the electricity in your home originates. The breakers or fuses are inside the panel and act as safety switches, shutting off power when there is an overload or short circuit.
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Wires - Electrical wires carry current throughout the home. Older homes generally have 60 amp service with two hot wires and one neutral wire. Newer homes usually have 100, 150 or 200 amp service requiring thicker gauge wires.
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Outlets and switches - Outlets provide connection points to plug in devices. Switches control lights and other permanent fixtures. These are fed by the wiring running through your walls, ceilings and floors.
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Grounding - Grounding protects you from shock in case of a short circuit or other electrical fault. Older homes often lack proper grounding, putting you at risk.
How Electrical Current Flows
Understanding how current flows is vital for wiring a home safely. The current originates from the main service panel and gets distributed through the hot wires. It powers devices along the way and returns through the neutral wires. The ground wires serve as emergency pathways if there is a fault.
Key Safety Tips
- Turn off power at the main breaker before starting work
- Test wires with a non-contact voltage tester to be doubly sure power is off
- Wear insulating gloves and be cautious not to touch bare wires
- Have a fire extinguisher on hand in case of accidental sparks
- Work slowly and carefully, double checking connections before restoring power
Developing an Improvement Plan
Before purchasing supplies and starting the rewiring process, it is crucial to make a detailed plan for the upgrades you want to make.
Here are some key considerations for developing your electrical improvement plan:
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Circuit mapping - Map out which fuses or breakers control each section of your home's lights, outlets and devices. Label everything clearly.
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Safety hazards - Inspect for exposed wiring, overloaded circuits, lack of grounding wires and other fire or shock risks. These will be top priorities to address.
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Efficiency upgrades - Consider adding circuits, upgrading wire gauge to allow for higher amperage, adding 240V circuits for large appliances, etc.
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New fixtures - Make a list of where you want to add new hardwired fixtures like ceiling lights, exhaust fans, etc. This will factor into the new wiring.
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Future needs - Account for upgrades like electric vehicle charging, backup power, smart home technology, etc. that you may want in the next 5-10 years. Design system capacity to allow for these.
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Budget - Factor in costs for all required materials and supplies. Rewiring an entire home can cost $1000 to $5000. Prioritize improvements if needed to meet your budget.
Obtaining Necessary Permits and Inspections
Check with your local permitting office to determine what permits and inspections are required for home electrical work. At minimum, you will likely need:
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Electrical work permit - Required for any significant electrical modifications.
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Final inspection - Ensures work meets National Electrical Code safety standards.
Providing details of the scope of your project when applying for permits can ensure you are aware of all code requirements from the start. Failing to get proper permits can also cause issues with your home insurance if electrical work is not done to code.
Safely Shutting Off Power
The first step in the rewiring process is to shut off power to the sections of the home you'll be working on.
Follow these safe practices:
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At the main breaker panel, switch the main breaker to the "Off" position to disconnect power from the utility lines feeding into your home.
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Test wires with a non-contact voltage tester before beginning work to confirm power is off. Check wires in multiple areas including outlets and light switches.
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Once certain the power is off, remove the front panel from the breaker box.
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Now switch all the individual circuit breakers to "Off" as well.
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With all breakers off, check wires again with a voltage tester to be absolutely sure.
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Place a warning sign on the breaker panel advising others not to restore power.
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For extra precaution, you can also unscrew individual fuses. Store them safely until the rewiring is complete.
These steps are crucial to prevent electrocution or injury while working on the electrical system.
Upgrading the Service Panel
If your home still has an outdated fuse box or the existing breaker panel is low capacity, upgrading the central service panel may be needed. This involves:
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Selecting a new breaker panel that meets your capacity needs and has ample slots for circuits.
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Running new service wires from the utility connection to the new panel location if moving it. This may require installation of a new meter by your utility company.
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Removing the old panel and disconnecting all the existing wiring.
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Mounting the new panel securely and reconnecting the service wires.
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Attaching all the existing branch circuit wires to the appropriate new breakers. Follow the circuit mapping you completed earlier.
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Adding any new dedicated circuits based on your improvement plan.
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Properly grounding the new service panel if the old one lacked a ground wire.
This is the time consuming part of the rewiring process. Taking it slow and being meticulous in your connections is important.
Running New Wiring as Needed
If you need to run new wiring for added lighting, outlets, switches and appliances, follow these tips:
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Use the proper gauge wire for expected electrical load. For common 15 to 20 amp branch circuits, 14 gauge wire is sufficient.
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Choose copper wiring over cheaper aluminum wire which can cause safety issues over time.
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Use NM-B cable with a ground wire for all new branch wiring you run. This provides vital protection.
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Carefully measure and cut wires to required lengths with extra slack. Don't make them too tight.
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Fish wires through walls and ceilings using proper tools. Follow local building codes for running wires.
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Use wire staples every few feet when running wires through framing studs or joists in unfinished areas like basements and attics. This secures them safely.
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Maintain at least 6 inches of separation between power and low voltage wiring. Cross at 90 degree angles when necessary.
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Label all new wires clearly at both ends indicating the circuit they are part of. This avoids confusion later.
Take precautions not to staple through or otherwise damage wires as you install them. Leave access points for inserting fish tape when wiring in finished walls.
Installing New Lights, Outlets and Switches
The fun part is finally installing all the new fixtures and devices in your rewired home! Follow these guidelines:
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Choose lighting, outlets, switches and covers that match your home's style and design. Maintain consistent look.
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For hardwired lights, connect the hot, neutral and ground wires properly to the fixture with twist-on connectors.
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Wrap connections with electrical tape for insulation and security. Follow light mounting instructions.
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For outlets, attach the wires to the hot, neutral and ground screws or clips. Secure the outlet in the electrical box.
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For switches, connect the hot wires to the switch screws and the neutral wires to each other. Ground the switch as well per manufacturer instructions.
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Arrange wires neatly in the boxes with cable clamps. No bare wires should be exposed.
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Affix faceplates and test each fixture to ensure proper function before moving on. Note any issues to troubleshoot later.
Follow building codes for outlet and switch heights and spacing. Group them logically. Labelling the breakers powering each run will simplify future circuit identification.
Safety Check and Power Restore
You're almost ready to enjoy your upgraded electrical system. But first:
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Double check all connections are tight with no exposed conductors or hazards
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Ensure no wires are pinched or penetrated that could cause a short
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Confirm proper grounding and bonding throughout
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Verify adherence to all electrical codes for your area
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With the main breaker still shut off, restore power to individual circuits one at a time. Check for proper function before moving to the next.
If all checks out, restore the main breaker last. Confirm all fixtures, lights and outlets function properly. Address any identified issues.
Finally, have an experienced electrician or your local building inspector perform a final safety check before considering your project complete.
Maintaining Your Improved Electrical System
Follow these tips going forward to keep your home's electrical system running safely for years to come:
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Never replace breakers with higher amp models than labeled on panel. This can overload and damage wiring.
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Tighten any loose electrical connections identified immediately to prevent hazards.
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Consider adding arc fault (AFCI) and ground fault circuit interrupter (GFCI) breakers for improved safety.
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Label any new circuits added down the road. Keep the circuit map up to date.
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Have an electrician inspect your panel and wiring every 3-5 years for preventative maintenance.
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Watch for any discolored outlets or switches, buzzing from fixtures, or flickering lights which may indicate issues.
By proactively maintaining your home's electrical system, you can enjoy optimal safety, efficiency and functionality for the long run.
Rewiring your home's electrical system without hiring a professional is a major undertaking, but also tremendously rewarding. By following the comprehensive guide above and always putting safety first, you can take control of your home's electrical system and enjoy the upgrades for years to come. Let me know if you have any other questions!