How to Rewire Your Home Without Hiring an Electrician (Step-by-Step Guide)

Introduction

Rewiring a home can seem like an intimidating task, but with proper planning and safety precautions, it's possible for a homeowner to do it themselves without hiring an electrician. As someone who has rewired parts of my home, I've learned that taking it slow and steady is crucial.

In this guide, I'll walk through the step-by-step process I followed to rewire rooms in my home safely and legally. I'll cover planning and preparation, wiring materials and tools needed, safety protocols, shutting off power, removing old wiring, installing new circuits, connecting wires, grounding, covering work, and testing.

While some electrical work does require a professional electrician, there are many rewiring tasks a knowledgeable homeowner can take on. This guide will give you the key steps so you can gain essential electrical skills and save on electrician fees.

Planning and Preparation

Before beginning any electrical work, the first critical steps are proper planning and preparation. Rushing into a rewiring project blindly can be unsafe and lead to costly errors.

Evaluating Electrical Needs

• Carefully evaluate which rooms or areas of the home need rewiring and why. This could be to replace outdated wiring, increase capacity, or add new circuits.

• Consider plans for any future additions or appliance upgrades that may impact electrical loads. Rewiring now can prepare for future needs.

Permits

• Verify what electrical permits are required in your local area before starting. Many jurisdictions require homeowner permits for significant electrical work.

Circuit Mapping

• Use your home's electrical panel to map out existing circuits and their loads before removing any wiring. This provides a reference for the new setup.

Shutting Off Power

• Identifying the main breaker shutoff switch and how to safely use it is paramount. I will go into detail on power shut-off later in this guide.

Budgeting and Costs

• Factor in costs for materials, tools, and permits. Rewiring is an investment that usually pays off long-term in electrical safety and functionality.

Materials and Tools Needed

Before getting started, ensure you have the right materials and tools on hand. This will make the rewiring process much smoother.

Electrical Wiring

• Use the correct gauge (thickness) of copper wiring based on expected electrical load and follow local codes. Commonly used gauges are 14, 12, or 10 AWG.

• Never use aluminum wiring, which is unsafe for home branch circuits. Stick with copper for all conductors.

• Have an ample supply of THHN wiring. This is standard single conductor wiring for homes.

• Ensure any wiring insulation meets building codes. Modern wiring has color-coded THHN insulation.

Conduit and Boxes

• Have the necessary electrical boxes for fixtures, receptacles, and junctions. Plastic or metal boxes both work.

• Stock up on various conduit types and sizes to protect wiring between boxes. EMT metal conduit and plastic PVC conduit are common.

Breakers and Panels

• Buy any new circuit breakers needed for new branch circuits you'll be installing. Match breaker amperage to wire gauge.

• If also replacing the main panel, get one large enough for all existing and new circuits you need.

Tools

Basic tools needed include:

• Wire stripper
• Voltmeter
• Screwdrivers
• Hammer
• Drill
• Hole saw
• Handsaw
• Level
• Tape measure
• Utility knife

Also have appropriate safety gear like eye protection, work gloves, ear protection for drilling, and insulated tools.

Shutting Off Power

Before touching any wiring, power to the home's electrical system must be completely shut off at the main breaker. Failing to do this properly can result in severe electrocution.

To shut off power:

• Locate the main breaker panel and identify the main shut off breaker. This controls power from the street to your home's circuits.

• Flip the main breaker to the OFF position. Verify power is off by checking for current with a voltmeter.

• Once you've safely shut off power, you can start removing old wires. But always double check for live wires during work with a voltmeter, before touching any wires.

• Keep the main breaker OFF until all wiring work is completed. Never restore power until the steps outlined later for testing and turn-on.

Removing Old Wiring

With power shut off, you can start removing any outdated, unsafe, or insufficient wiring in the rooms being rewired.

To properly remove old wiring:

• Carefully pull individual wires out of their conduits or disconnect them from fixtures and boxes. Coil wires for safe removal.

• For conduit removal, use a handsaw to cut conduit sections for extraction. Unscrew conduit fittings to disassemble.

• Make note of all box and conduit locations being removed. These provide a template for new setups going in the same areas.

• Properly dispose of removed wiring components. Never just leave wires in walls.

• Remove any abandoned junction boxes no longer needed. Seal over holes left in walls.

The goal is to gut the room down to the bare studs, with power safely disconnected. Now new wiring can be installed.

Installing New Circuits

With the room gutted, it's time to install the new wiring system. Focus on one circuit at a time.

Laying Out Wires

• Plan the layout of each circuit from the panel to the rooms and fixtures it will serve. Avoid crossing circuits.

• Measure wire runs and cut wires to length as needed, allowing extra length for connections. Use THHN wires in appropriate gauge.

• Neatly run wires through drilled holes in wall studs. Secure wires to studs using insulated staples every 2 feet.

Conduit and Boxes

• Install new junction boxes and conduit where you want switches, fixtures, receptacles, etc. Follow codes for box placement.

• Run protective conduit between boxes and locations where wires are exposed. Anchor conduit securely.

• Use metal EMT conduit for dry locations and PVC for wet areas like bathrooms. Never use metal conduit for 240V.

Connecting Wires

• Use wire nuts to connect circuit wires within boxes to corresponding fixtures, switches, and receptacles.

• Establish pigtail connections when needed to split to multiple devices. Group neutrals and grounds separately.

• Ensure connections are tight and insulated. Follow diagrams for proper connections of switches, receptacles, and fixtures.

Grounding

Proper grounding of new wiring is vital for safety. Here are key grounding steps:

• Run a continuous bare copper ground wire in each new circuit back to the main panel ground bar.

• Bond all new metal boxes and conduit to the ground wire using scrap pieces of wire and grounding screw terminals.

• Connect all new appliance and fixture grounds to the circuit grounding wire using wire nuts or terminals.

• Verify ground continuity in all locations using a multimeter. Check for 0 Ohms resistance.

Never electrify circuits without properly grounding them first. This protects against electrocution and shock.

Covering Work

Once new wires are installed, the final stage is covering up your work.

• Mount new electrical boxes securely where needed. Apply cover plates.

• Patch over conduit holes and junction boxes in wall studs using metal plates or wood patches.

• Replace any drywall or panels removed to access wiring. Mud, prime, and paint patched drywall.

• Fireblock any new gaps around wires using fire-rated caulk, foam, or mortar. This seals passages fires could spread through.

• Label all new wires clearly at access points like boxes and the panel. This helps identify circuits later.

Testing and Turn-On

With everything buttoned up, it's time to test and turn the power back on. Work methodically box-to-box to confirm safety and functionality.

• Visually inspect all connections and junctions closely for any exposed wire or issues.

• Verify grounding and GFCI protection are properly set up.

• Flip the main breaker ON and methodically test each new circuit:

  • Check for power at the panel breaker using a voltmeter before energizing the circuit.

  • With the circuit off, plug in a voltage tester and turn on power. Walk the circuit carefully, testing each box and fixture for power. Address any issues found.

  • Turn the circuit on and visually check all fixtures and receptacles function properly. Verify light switches control the intended fixtures.

• Consult an electrician if you have any doubts about safety. Only turn everything on once you've fully tested each circuit.

• Once live, your new wiring is complete! But periodically check connections and grounding for issues over time.

Summary

While rewiring a home is complex, it can be tackled successfully by an informed homeowner using proper materials, safe procedures, and methodical installation and testing of new circuits.

The keys I've learned are turning power fully off, running wires into code-approved boxes and conduit, making failsafe connections, ensuring robust grounding, and thoroughly testing operation before energizing circuits.

Taking this gradual, safety-first approach allows you to gain substantial DIY electrical skills and the satisfaction of providing your home with up-to-date, safe, and robust wiring.