Wiring a home can seem daunting, but with proper precautions and some key tips from professionals, you can update or install new wiring safely. Follow these guidelines to avoid electrical fires or shocks when working on your home's electrical system.
Research Permit Requirements
Before starting any electrical project, be sure you understand your local permit requirements. Many jurisdictions require homeowners to obtain permits for electrical work beyond basic repairs or replacing existing fixtures like lights or outlets.
Pulling permits ensures your work will be inspected for safety. Trying to bypass permits can risk fines, insurance issues if a problem arises, and even complete rework if the wiring violates code.
Key Permit Triggers
Permits are often needed for:
- Adding new circuits or outlets
- Upgrading service panel/breaker box
- Rewiring all or part of the home
- New hardwired appliances like AC units
Check with your local building department to understand permit rules in your area. Securing permits upfront is far easier than undoing improper work later!
Turn Off Power at the Breaker Box
Before touching any wires, the power must be completely disconnected to avoid shocks.
At the main breaker box,:
- Switch the main breaker to OFF. This shuts off power from the utility lines to your home.
- Turn OFF all individual breakers. There may still be some residual power even with the main breaker off.
- Verify power is off by testing outlets with a multimeter or plug-in tester.
Trying to work on wires while they are live risks severe injury or death by electrocution. Always fully disconnect the power first.
Wear Protective Gear
Even with the power off, Electrical work requires specialized protective equipment to stay safe. Wearing proper clothing and safety tools should be part of your preparation routine before wiring work to reduce risks.
Recommended Protective Gear:
Rubber-soled shoes - Avoid cloth or leather shoes that conduct electricity
Insulated gloves - Protect hands from accidental contact with wires
Safety goggles - Prevent eye injuries from sparks or loose wire ends
Long sleeve shirt and pants - Avoid exposed skin contact with wires
Face mask - Guard against inhalation of insulation particles
Fire extinguisher - Have ready access for emergency control of electrical fires
Use Extreme Caution with Aluminum Wiring
While copper wiring is generally recommended for safety and performance, some older homes used aluminum wiring which requires extra precautions.
Aluminum wiring risks:
- More prone to corrosion and loose connections
- Higher expansion/contraction with temperature changes
- Higher failure rate at connections compared to copper
If your home has aluminum wiring, exercise extreme care:
- Inspect all connections for corrosion and secure fit
- Use special connectors and compounds made for aluminum
- Consider rewiring with copper for optimal safety
Leaving old aluminum wiring untouched risks dangerous electrical failures. Address it properly when doing wiring projects.
Install GFCI Outlets Near Water Sources
Any outlets located near water sources like kitchens, bathrooms and laundry rooms require special GFCI (ground fault circuit interrupter) outlets for protection.
GFCI outlets have built-in circuit breakers that quickly cut power if abnormal current flows are detected, helping prevent shocks. GFCI protection should be installed:
- Within 6 feet of sinks, tubs, showers
- For outlets near pools, hot tubs and outdoor water fixtures
- In unfinished basements and crawl spaces prone to moisture
- For garages, accessory buildings and outdoor outlets
Upgrading to GFCI outlets is an easy precaution providing valuable protection from electrocution risks near water.
Use the Proper Wire Gauge and Types
Selecting the appropriate wire gauge (thickness) and insulation material is critical for safety and efficient power flow.
For 15 amp general purpose circuits, use 14 AWG copper wire with plastic THHN insulation
For 20 amp circuits like kitchens, bathrooms and major appliances, use 12 AWG copper THHN wire
For high power devices like AC units, electric dryers and stoves, use 10 AWG copper THHN wire
For the main service entry wires, sizes of 2/0 AWG to 4/0 AWG are common
Never use undersized wire unable to handle the electric load - this can cause hazardous overheating and fires. Consult an electrician if unsure what gauge your specific wiring project requires.
Label All Circuit Breakers
With the power turned off, take time to properly label each circuit breaker in the service panel before working on any wiring. Breakers should clearly indicate which rooms or outlets they control.
This allows quickly shutting off specific circuits later for repairs, and ensures you can deactivate the correct breaker if a problem arises during wiring work. Breaker labels are a basic safety essential.
Inspect the Service Entry Mast
For whole home rewiring projects, take the opportunity to examine the service entry mast where power lines enter from the utility pole.
Look for any:
- Corrosion or rust
- Damage from weather or birds/rodents
- Older non-weatherhead masts prone to water getting in
Address any issues found to avoid future hazards. A professional electrician can often replace an old mast quickly during rewiring.
Secure All Electrical Boxes
Before running any new wire, ensure existing and new electrical boxes are securely anchored.
- Loose connections to joists or studs
- Damage to mounting ears from overtightened screws
- Cracked or brittle plastic boxes
Reinforce any problem boxes with additional mounting supports or replace them entirely as needed. Secure boxes prevent wires from pulling loose during use.
Run Wires Properly Through Studs
When running wiring through studs, be mindful of:
- Drilling holes centered so wire insulation doesn't contact exposed wood
- Keeping wires at least 1-1/4" away from the edge of studs
- Avoiding contact with plumbing, ducting or other items in the stud bay
Protect wires with metal plates if drilling near the edge of a stud to prevent nails from hitting them. Safe wire routing protects against shorts and shock hazards.
Connect Switches and Outlets Properly
Improperly wired connections at switches, outlets and junction boxes can lead to fires or malfunctioning circuits.
To confirm safe connections:
- Match wire colors to terminal screws (black to brass, white to silver)
- Wrap solid wires clockwise 3/4 turn around screws
- Use push-in connections properly with right strip length
- Tug test wires to verify tight connection
- Use electrical tape on wire nuts for a secure bond
- Double check outlets are grounded if required
Take the extra time to make reliable, long-lasting connections that won't fail over time.
Keep Wires Neat and Organized
While working, group wires together and tie off neatly. Don't let loose wires lay randomly in boxes or the attic/basement.
Benefits of neat wiring:
- Reduces risk of loose wires touching and shorting
- Simplifies testing connections
- Allows covering boxes completely to contain sparks
- Improves troubleshooting if repairs are needed
- Minimizes fire hazards from loose wires
Proper wire management is about both aesthetics and safety. Take pride in your work.
Have an Electrician Inspect the Work
Once the new wiring is complete, call a licensed electrician to:
Verify all connections are properly secured with no exposed conductors
Check appropriate wire types and sizes were used for each circuit
Confirm grounding and GFCI protection meets code
Review entire installation for flaws that could create hazards
Professional inspection gives peace of mind that your DIY electrical work is safe and ready for use. Don't skip this important final step before turning the power back on.
Wiring a home without experience carries risks, but taking precautions like obtaining permits, using safety gear, killing all power, and hiring an electrician to inspect allows you to upgrade electrical safely. Follow these tips to avoid burning your house down!