How to Replace Electrical Wiring in Your Home
Introduction
Replacing the electrical wiring in your home is an important project that requires careful planning and execution. Faulty wiring is a fire hazard and can cause electrocution, so upgrading old, damaged, or insufficient wiring should not be put off. This article will provide a step-by-step guide to replacing electrical wiring, from deciding when it's time to replace the wiring, getting the necessary permits, selecting wire and outlets, installing new wiring and fixtures, to final inspection and testing. I will cover safety procedures, costs, and tips to make your electrical rewiring project go smoothly.
When to Replace Electrical Wiring
Here are some signs it may be time to replace the electrical wiring in your home:
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Frequent tripped circuit breakers or blown fuses: This usually means you are overloading the circuits or there is a short or loose connection somewhere.
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Dimming lights or flickering lights: This can indicate the wiring cannot handle the electricity load.
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Old wiring: Homes older than 40 years likely have outdated wiring that needs replacement.
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Aluminum wiring: Aluminum wiring was used in homes built between 1965 to 1973. It is prone to overheating andarc faults, so should be replaced with copper wiring.
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Not enough circuits or outlets: If your home lacks enough circuits or outlets for all your modern devices and appliances, the wiring should be upgraded.
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Planning renovations or additions: Any major renovation is a good opportunity to upgrade old wiring.
Getting Electrical Permits
Contact your local building department to get any required permits before starting electrical work. Permits are usually required when:
- Replacing the main electrical service panel
- Adding new circuits
- Adding new hardwired appliances like air conditioners
- Doing major appliances upgrades requiring new wiring.
Make sure any electricians you hire are licensed and insured. Get copies of their license and insurance certificate.
Choosing Wiring
For any new wiring, use copper wire over aluminum. Here are the recommended gauges:
- 15 amp circuits: Use 14-gauge wire
- 20 amp circuits: Use 12-gauge wire
- Large appliances: Use 10-gauge wire
- High voltage appliances like dryer: Use 8-gauge wire
Also choose wiring with enough strands. Look for wire labeled "stranded THHN" which is more flexible and less prone to breaking with movement.
Selecting New Outlets and Switches
When replacing wiring, it's best to also upgrade outlets and switches. Choose tamper-resistant outlets which prevent children from inserting objects. GFCI outlets provide protection from electrocution near water sources like kitchens and bathrooms. Smart switches allow controlling lights remotely. Match metals throughout for a consistent look.
Running New Wiring
Follow these steps to run new wiring:
- Turn off power at the main breaker panel. Verify it is off!
- Remove existing outlets, switches and fixtures.
- Run the new wires between the panel and outlets. Secure wires at least every 4.5 ft with staples or clips.
- Use wire connectors to splice wires together. Wrap connections with electrical tape.
- Attach wiring to new outlets, switches and fixtures.
- Label each wire at both ends for easy identification. Color coding helps.
- Ground all wires, boxes and devices properly using ground screws or wires. This provides a safe path for electricity in case of defects.
Installing New Breaker Panel
If the main breaker panel also needs replacement, be sure to get the proper amperage capacity for your home. Turn off the main breaker as well as individual breakers. Then follow manufacturer instructions to install the new panel and connect all the wiring. Properly label all circuits.
Final Testing and Inspection
With all new wiring in place, turn the power back on and carefully test each circuit. Plug a lamp into each outlet to verify operation. Turn switches on to test lights. Check for secure connections by gently tugging wires. Finally, contact the building inspector to schedule the final inspection before concealing any wiring.
Replacing electrical wiring is a project best left to professionals. But if you educate yourself, get proper permits, and follow safety procedures, it can potentially be a DIY job. Make sure to research local building codes and get professional advice when needed. With upgraded wiring, your home will be safer and better equipped to handle modern electrical needs.