Rewiring your home's electrical system can seem like a daunting task, but with proper planning and safety precautions, it is possible for a dedicated DIYer to take on significant electrical projects. As an experienced homeowner who has successfully rewired parts of my home, I want to share my advice on how to do this in a safe and effective manner without hiring a professional electrician.
Understanding Electrical Basics Before Rewiring
Before attempting any rewiring project, it's crucial to understand some basic electrical principles and safety guidelines. This knowledge will allow you to work safely and carry out the rewiring properly. Some key things I learned include:
Electrical Current, Voltage, and Circuits
- Current is the flow of electricity measured in amps.
- Voltage is the "pressure" of electricity measured in volts. Most homes have 120V and 240V circuits.
- A circuit is a closed loop of flowing electric current from the main panel through wires and a switch to an outlet and returning.
How Electrical Wiring Works
- Insulated wires inside wall cavities and conduits carry current to outlets, switches, and appliances.
- Wires connect to breakers or fuses in the main service panel which distribute electricity.
- Neutral wires carry current back to the panel. Ground wires protect from shocks and shorts.
Electrical Safety Fundamentals
- Assume all wires are "hot" (live) when working. Turn off power at the main breaker.
- Use caution and non-conductive tools when handling wires.
- Only work on de-energized circuits with breakers turned off or fuses removed.
- Triple check wires with a voltage tester before touching.
Spending time to learn these basics provides the foundation to safely rewire electrical systems. I highly recommend getting an authoritative book like Home Electrical Wiring: A Complete Guide to DIY Electrical Projects to study before any work.
Creating a Rewiring Plan
The next essential step is creating a detailed plan for the rewiring project. Rushing into electrical work without a plan is dangerous and often leads to mistakes or poor performance. My plan includes:
Evaluating the Current Wiring
- Inspect the existing wiring to see if it needs upgrades, repairs, or replacement.
- Check for problems like old cloth-wrapped wire, undersized wires, aluminum wiring, or damaged cables.
- Assess if it's feasible to just replace certain problem wiring instead of a whole-home rewire.
Determining New Wire Size and Type
- Calculate electrical load and size new wires accordingly. Consider larger #10 or #8 wire for high draw appliances like dryers.
- Use copper wiring rather than aluminum. Choose insulated THHN/THWN-2 wire.
Mapping Out New Circuits and Layout
- Add dedicated circuits for heavy appliances like refrigerators and air conditioners.
- Include more circuits than existing to prevent overloads.
- Sketch circuit routes from the panel through walls/ceiling to outlets.
- Plan for better positioned outlets and switches.
Allowing for New Electrical Features or Appliances
- Consider wiring for extra phone, TV, internet, or audio jacks.
- Accommodate plans for additions like electric vehicle chargers, tankless water heaters, or HVAC upgrades.
Budgeting Time and Costs
- Create a parts list with estimated costs for breakers, wire, outlets, switches, and conduit.
- Factor in drywall repairs, painting, permits, and dump fees.
- Budget ample time for such a major project.
Making a thorough rewiring plan is crucial preparation before purchasing supplies and beginning work. It helps make the project more manageable, safer, functional, and cost-effective.
Step-by-Step Process for DIY Home Rewiring
Once an excellent plan is in place, it's time to roll up your sleeves and get to work. Follow these steps to systematically rewire a home:
Turn Off Main Power and Install New Breaker Panel
- Shut off the main breaker and verify power is off with a voltage tester.
- Remove old breakers and service entrance wires.
- Mount and connect new 200 amp panel according to code if upgrading.
Run New Circuit Wires from Panel to Outlets
- Cut access holes and drill entry points between wall studs.
- Fish plastic electrical conduit through walls and ceilings.
- Pull insulated copper THHN wires through conduit from panel to circuits.
Connect Outlet, Switch, and Junction Boxes
- Install electrical boxes throughout the house for devices and wire splices.
- Secure boxes and run circuit wires into them.
- Connect wires to outlets, switches, and other endpoints.
Label and Mount New Devices and Fixtures
- Use wire nuts to splice lead wires from fixtures to circuit wires.
- Affix device mounting brackets.
- Attach covers and install lights, fans, etc.
Update Ground Wires and Install GFCIs
- Run new ground wires from panel to boxes.
- Connect fixtures to grounds for shock protection.
- Use GFCI outlets for kitchen, baths, laundry, and outdoor plugs.
Inspect, Test and Turn Power Back On
- Verify all connections are tight with no exposed conductors.
- Turn on breakers and test each circuit for proper function.
- Check lights, outlets, and appliances in each room.
By methodically following these steps, I successfully installed all new modern wiring in sections of my home. While rewiring an entire house this way takes time and diligence, it greatly improves electrical safety.
Helpful Tools and Materials for Home Rewiring Projects
Completing a residential rewiring project requires having the right tools and materials on hand. Through my experience, these items are very useful to have:
- Voltage tester - Detects live power to avoid shocks
- Wire stripper - Removes insulation from wire ends
- Lineman's pliers - Grips, twists, cuts wire
- Fish tape - Snakes wires through walls
- Cable ripper - Splits out old wiring
- Electrical tape - Insulates wire connections
- Wire nuts - Joins and splices wires
- Electrical boxes - Houses wiring splices and mounts devices
- Cable clamps - Secures wires entering boxes
- Conduit - Protective tubing for wire runs
- Copper THHN wire - Various sizes for circuits
- GFCI outlets - Prevents shocks near water sources
Having these supplies makes it much simpler to run wiring, join conductors, install boxes, mount devices, and work safely. Invest in high-quality electrical hand tools and materials from reliable brands.
Hiring an Electrician for Big Rewiring Jobs
While many home electrical projects can be DIYed, some rewiring tasks are better left to licensed electricians. Consider hiring a pro for:
- Whole-house rewiring - Safer for large projects due to complexity
- Upgrading main service panel - Requires working at the meter/utility feed
- Adding new major appliances - May need special wiring requirements
- Integrating smart home tech - Automation systems have intricate wiring
Professional electricians have years of training and experience. They can perform complicated electrical work more efficiently and safely. Get references and compare several quotes before choosing an electrician for big jobs.
I hope these insights give you a great starting point for planning and tackling DIY electrical rewiring projects confidently and safely. Let me know if you have any other questions!