Rewiring electrical outlets and lights in your home can be a daunting task, but with proper precautions it can be done safely without burning down your house. As a novice homeowner attempting electrical work for the first time, I learned through trial and error how to rewire outlets and lights without electrocuting myself or burning my house down. Here is my guide to walk you through the process step-by-step.
Understanding Electrical Basics
Before attempting to rewire any part of your home's electrical system, it's important to understand some basic electrical concepts and terminology:
Electricity and Current
- Electricity is the flow of electrons through a conductor like copper wire.
- Current is the amount of electricity flowing through a wire measured in amps. More current can increase the risk of overheating wires.
Voltage and Circuits
- Voltage is the "pressure" that pushes electricity through wires measured in volts. Most household circuits are 120v. Higher voltage is more dangerous.
- A circuit is a closed loop of wires through which electricity flows from the main service panel through outlets and switches and back.
Grounding and Neutral Wires
- The neutral wire conducts current back to the service panel.
- The ground wire protects from shocks and conducts current in emergencies.
- Proper grounding is crucial for safety.
With key terms defined, let's look at gathering the right tools and materials.
Gathering Necessary Tools and Materials
Rewiring electrical work requires some specialized tools and materials. I made sure to gather all of these before starting work:
- Wire strippers - For stripping insulation off wires
- Voltage tester - To safely check if wires are live
- Clamp meter - To measure current flow
- Outlet and switch testers - Confirm proper wiring
- Insulated screwdrivers - Ensure you don't get shocked
- Wire nuts - For joining copper wires together
- Electrical tape - Insulates wires and connections
- 12/2 NM cable - Flexible insulated copper wire for circuits
- Electrical boxes - Houses outlets and switches
Safety first! Be sure to wear personal protective equipment including safety goggles, gloves, long sleeves and pants without holes.
Turning Off Power at the Breaker
Before touching any wires, use a non-contact voltage tester to be sure, but start by turning off power at the main circuit breaker panel.
To turn off power:
- Locate the main breaker panel in your home, usually in the basement, garage or laundry room.
- Open the metal door and locate the main breaker switch.
- Flip the main breaker to the "Off" position.
- Check outlets with a voltage tester or clamp meter to confirm power is off.
With the power off, we can now safely work on the dead outlets and wires throughout the home.
Removing Old Outlets and Switches
To replace an outlet or switch, the first step is to remove the existing one:
- Unscrew and remove the cover plate from the outlet/switch.
- Unscrew the mounting screws holding the outlet/switch in its electrical box.
- Carefully pull the outlet/switch out of the box without damaging the wires.
Pay attention to where each wire is connected as you will need to replicate these connections. Take pictures if needed.
If wires are bundled together with wire nuts, gently disconnect by unscrewing the nut and separating the wires. Place nuts back on the ends of each wire to avoid fraying.
Rewiring a New Outlet
Once the old outlet or switch is removed, it's time to wire up the replacement:
1. Connect the Ground Wire
- Find the bare copper ground wire in the back of the box that may be screwed to the box itself.
- Using a screwdriver, secure the new outlet's ground wire to this box ground.
2. Connect the Neutral (White) Wire
- Find the white coated neutral wire and connect it to the neutral silver screw terminal on the outlet.
- Fold it clockwise around the screw and tighten securely.
3. Connect the Hot (Black) Wire
- Locate the black coated hot wire that carries 120v electricity.
- Connect this wire to the hot gold brass screw terminal.
- Again, loop it clockwise and securely tighten.
4. No Loose Strands
- Make sure no copper strands are sticking out of the screw terminals.
- Tuck all wires neatly into the box.
5. Test Your Work
Before mounting the outlet, plug a tester into it to confirm correct wiring. The tester should light up correctly.
Once wiring is confirmed correct, mount the outlet back into the box and screw it in place. Replace the cover plate and turn power back on. Test the outlet again to make sure it works.
Rewiring a Light Fixture
Rewiring overhead lights involves a few extra considerations:
1. Turn Off Light's Power
Turn off power to the light at the breaker, then unmount the fixture from the ceiling to access the wires.
2. Connect the Grounds
Connect all ground wires, from fixture and ceiling box, to each other with a wire nut.
3. Connect Neutrals
Connect all white neutral wires together, usually splicing them into a larger wire going to the breaker.
4. Connect Hots
- Connect the wires sending power from the junction box to the hot fixture wires.
- Often this involves splicing hot wires from multiple fixtures together.
5. No Loose Strands!
Again check no copper wire strands are exposed from screw terminals. Tuck wires neatly into the ceiling box.
6. Secure the Fixture
Remount the light fixture to the ceiling box and screw it securely in place.
Turn power back on and test the switch. Make sure the light turns on and off correctly. Use a tester to confirm proper wiring as needed.
Helpful Rewiring Tips
Here are some helpful tips to keep in mind for a safe, successful wire rewiring project:
- Label all wires - Use masking tape flags to label wires as you disconnect them.
- Take pictures - Photo document all connections before disconnecting wires.
- Check polarity - Use a multimeter to verify hot vs. neutral wires.
- Mount securely - Make sure all electrical boxes and fixtures are well mounted.
- Use wire nuts - Always cap wires with wire nuts to prevent fraying.
- Cover boxes - All junction boxes should have covers to contain wires.
- Be organized - Neatly bundle and route wires to prevent hazards.
- Go slowly - Take your time and be deliberate to avoid mistakes.
By following these tips, along with proper safety precautions, you can tackle electrical rewiring projects with added confidence and prevent burning down your house! Just be sure to call an electrician if you feel unsure about any aspect of the wiring. Taking your time is well worth avoiding electrical fires or shocking experiences!