Introduction
Rewiring a home can seem like a daunting task, especially for those of us with no electrical experience. However, with the right precautions, tools, and step-by-step guidance, even the totally unqualified can rewire their home safely.
In this comprehensive guide, I'll walk you through everything you need to know to rewire your home without burning it down or getting electrocuted. I'll cover safety procedures, circuit requirements, selecting wire gauge and type, installing new wiring and outlets, connecting to the main panel, testing your work, and more.
Safety First
Before you even think about touching your home's electrical system, safety should be your top priority. Rushing into a rewiring project without taking precautions can easily lead to fire or electrocution hazards. Here are some key safety tips:
Turn Off Power at Main Panel
This is absolutely essential. Before doing any electrical work, switch off the main circuit breaker in your electrical panel. This cuts power to the entire house. Then, you should double check outlets with a voltage tester to make sure everything is dead. Working on live wires can be fatal.
Wear Protective Equipment
When handling wiring, wear rubber-soled shoes, gloves, long sleeves, safety goggles, and a mask. This gear will protect you from electric shock and wire strand cuts.
Install GFCIs
Ground-fault circuit interrupters (GFCIs) shut off power when a ground fault is detected. Install these at the start of every circuit to prevent electrocution. Test them regularly.
Get Permits and Inspections
Check your local building codes and get all required permits before starting. Have an electrician inspect your work after major steps and at completion before turning power back on.
Planning the New Wiring
To rewire correctly, you need to plan out the new wiring system carefully based on your home's size and layout.
Calculate Electrical Load
Add up the wattage ratings on all lighting fixtures, outlets, and appliances that will be on each circuit. Use this to determine the required amperage rating for each circuit.
Create a Circuit Map
Draw up a floor plan and map out each new circuit, marking all outlet and fixture locations. Group rooms and areas into separate circuits.
Select a Main Panel
Choose a main circuit breaker panel that can handle all your planned circuits with room to spare for future expansion. 200 amps is common for many homes.
Pick Proper Wire Size
Select the right wire gauge for each circuit based on the electrical load and circuit length using wire size charts. #12 or #14 gauge is usually sufficient.
Installing New Wiring and Outlets
With your new circuit map in hand, you can start installing the new wiring throughout the house. This takes time and patience, but can be managed by the unqualified step-by-step:
Run Cables Through Walls and Attic
Drill holes to run cables through walls vertically to each outlet or switch box. For horizontal runs, feed cables through attic or crawl space. Avoid exterior wall cavities.
Mount Outlet and Switch Boxes
Cut holes for each box location with a drywall saw or utility knife. Mount new plastic boxes with screws or nails. Follow your circuit map.
Pull Cables into Boxes
Carefully pull the end of each cable through to the proper boxes using fish tape. Leave extra wire at each box for connections.
Connect Outlets and Switches
Use wire strippers to remove 3/4" of insulation from each wire end. Secure hot, neutral, and ground wires to outlets and switches with screw terminals.
Install New Fixtures and Devices
Mount light fixtures, outlets, switches, and cover plates when wiring is complete. Test each one to ensure proper connectivity.
Connecting the Main Panel
The scariest part is connecting all those wires to the main circuit breaker panel. But it's manageable by carefully labeling each wire and connecting one circuit at a time.
Shut Off Main Power Again
Yes, double check that the main breaker is OFF! Working on a live panel can cause extremely dangerous shorts and electrocution.
Label All Wires
Label every cable end with the matching circuit number using tape. This keeps 120V and 240V wires separate and organized.
Connect Grounds First
Attach all ground wires to the ground bus bar first. Ensure they are tightly secured with screws.
Connect Neutrals
Next, attach neutral wires to the neutral bus bar in the same order. Double check connections.
Connect Hot Wires
Finally, attach the hot wires to their corresponding circuit breakers one at a time. This keeps hot wires isolated as you work.
Ensure Loose Wires Secured
Verify that all wires are firmly fixed. No loose strands or unlabeled cables. This can cause arcing faults.
Testing and Turning Power Back On
You've finished the hard part, but now it's time to validate that everything works properly and safely before re-energizing the circuits:
Turn Each Circuit On Individually
Turn on one circuit breaker at a time. Walk the circuit testing outlets, lights, and switches as you go. Verify proper function and no shorts.
Check All Connections are Tight
Remove panel cover and inspect each wire connection again for tightness. All lugs and bus bars should have no exposed copper.
Monitor Voltage
With everything energized, check voltage at outlets with a meter. Voltage should remain steady between 110V - 120V. Any fluctuations could indicate improper connections.
Get Final Inspection
With tests passed, get a final inspection by the building department. They will check all connections, grounding, and function.
Flip Main Breaker Back On
Finally, with approved inspection complete, turn the main breaker back on. Your home's new wiring should now be powering up safely!
Conclusion
While rewiring a home without experience can seem intimidating, safety is the key focus at every step. Following proper precautions, planning guidelines, installation procedures, and testing protocols can allow even the totally unqualified to rewire a house successfully. Just take it slow and be extremely careful when handling wiring. Your home will light up brightly once the job is done right!