How to Rewire Your Home’s Electrical System Safely and Affordably

Rewiring the electrical system in your home can seem like a daunting task, but it doesn't have to be with the right planning and preparation. As a homeowner, I learned firsthand how to rewire my house on a budget without compromising safety. In this comprehensive guide, I'll share everything I learned to help you update your home's wiring yourself.

Understanding Electrical Systems Basics

Before beginning any electrical project, it's crucial to understand some key electrical terms and components. This will help you plan your rewiring project appropriately and safely.

The Main Electrical Service Panel

The main service panel, or breaker box, is the central hub of your home's electrical system. This panel connects your home to the utility company's power lines and distributes electricity throughout your house through a system of breakers and wiring. The service panel and its components include:

• Main breaker - This controls power from the utility company to your home.

• Breakers - Individual circuit breakers that control power to specific sections of your home's wiring system.

• Buss bars - The hot and neutral bars that electricity flows through. Breakers clip onto these bars.

• Ground bar - A bar that grounds your electrical system for safety.

Key Electrical Terms

Some other key terms to understand include:

• Voltage - The force of electrical current, measured in volts (V). Most homes have 120-240V service.

• Amperage (amps) - The rate of electrical flow. Breakers and wiring must match electrical load amperage.

• Wattage - The amount of power drawn by an appliance, calculated by multiplying volts by amps.

• Circuit capacity - The max amps a breaker and wiring can safely handle. Standard is usually 15-20 amps.

Evaluating Your Existing Electrical System

Before planning your rewiring project, it's essential to thoroughly evaluate your existing electrical system. This involves:

Inspecting the Main Service Panel

• Check the main breaker amperage to determine how much power your home's electrical system can handle. This is usually 100, 150 or 200 amps for a typical home.

• Ensure the breaker amperages match the circuits they serve. See what rooms or appliances each controls.

• Check for signs of rust, corrosion, pitting or discoloration which can indicate issues.

• Note any double-tapped breakers, which overload circuits. These will need to be separated.

• Look for blank spots where breakers can be added if needed.

Evaluating Wiring and Fixtures

• Remove cover plates and inspect the condition of all wiring in outlets and switches. Look for cracking, exposed wire, heat damage or discoloration.

• Test outlets and switches with a voltage tester to check for faulty wiring with electricity flowing to the wrong wires.

• Note all fixtures, outlets, switches and appliances on each circuit.

• Identify areas of insufficient power – frequent tripped breakers or dimming lights can indicate this.

Considering Long-Term Needs

To plan for the future:

• Consider expanding breaker capacity if your home needs more power.

• Add circuits if certain rooms lack enough outlets or lighting.

• Upgrade outdated wiring that won't support additional safety features such as grounding or GFCI outlets.

Creating a Rewiring Plan

Once you have thoroughly evaluated your electrical system, it's time to map out your new wiring plan.

Choosing a Main Service Panel

If you have outdated fuse boxes, you'll need to upgrade to a modern breaker panel with enough capacity for your home. When choosing one, ensure it has:

• Enough breaker spaces for all existing and new circuits you need.

• Appropriate amperage capacity for your electrical usage needs.

• Ample room for future expansion.

• A main disconnect breaker.

Mapping New Breaker Circuits

Create a plan for new breaker circuits in the rewired electrical system:

• Divide rooms and uses logically, ensuring important devices have dedicated circuits.

• Don't overload circuits. Allow for future device additions as well.

• Include safety features like arc fault (AFCI) and ground fault circuit interrupter (GFCI) breakers where required.

• Make sure total amperage per circuit doesn't exceed the breaker and wire capacity.

Selecting Updated Wiring

Choose the right new wires for each circuit:

• Use 12 or 14 gauge copper wires for 15-20 amp residential circuits.

• Select 3 wires (hot, neutral, ground) for all 120V circuits.

• Use thicker wires for higher voltage 240V circuits like for HVAC units or dryers.

• Choose wire jackets in appropriate colors for hot (black), neutral (white), and ground (green).

Creating a Detailed Diagram

With all details mapped out, create a detailed wiring diagram to follow for the rewiring. Include:

• All circuits, breaker sizes, and connections.

• Exact wire routes from the panel to outlets and fixtures.

• All outlet, switch, and fixture locations.

• Any new lighting, receptacles, switches etc. to add.

Safety Gear for Rewiring

Electrical work can be hazardous. Before starting any rewiring, you must gear up with proper safety equipment:

• Electrical gloves to insulate hands from shock. Leather protectors go over regular rubber gloves.

• Safety glasses protect eyes from hazards.

• A face shield provides additional face protection when working closely.

• Long sleeves and pants prevent accidental skin contact with wires. Choose non-flammable materials.

• Electrical boots with reinforced soles grounded to the floor help prevent shock.

• Have a fire extinguisher on hand in case of electrical fire.

• Work with a partner who can power off electricity or get help in an emergency.

Step-By-Step Process for Rewiring

Once fully prepped, you're ready to tackle the rewiring project. Follow these key steps:

Turn Off Main Power

Turn off the main breaker in the service panel and verify power is off with a voltage tester before starting any work.

Remove Old Wiring

• Take out the old wires from outlets, switches and fixtures as you go.

• Either pull them out completely or clip them to remove from the circuit.

• Take down any abandoned wires that aren't part of your new plan.

Install New Wiring Infrastructure

• Run all planned new circuit wires from the panel through walls and ceilings to each outlet and switch box.

• Staple or clip wires neatly at regular intervals.

• Ensure wires are color-coded correctly.

Connect Devices to New Wires

• Connect the hot and neutral wires to the correct terminals on each outlet, switch and appliance.

• Attach all ground wires to grounds.

• Wrap all connections with electrical tape for safety.

Label and Organize New Panel

• Label all new breakers clearly.

• Tidy up all the new wiring neatly in the panel.

• Verify breakers match their circuits.

Inspect, Test and Restore Power

• Visually inspect all connections and wiring.

• Turn power back on and methodically test each circuit.

• Check for secure fit by tugging wires in outlets and switches.

Once all circuits check out, you can change out switch, outlet, and fixture covers and restore power!

Tips for Rewiring Your Home Safely

Follow proper precautions when rewiring your electrical system:

• Power off locally before working on any circuit. Never assume it's dead. Verify with a tester.

• Connect only 1 wire at a time so you don't mix up hots and neutrals.

• Keep wires trimmed to proper lengths to avoid excess copper that can touch other terminals.

• Use junction boxes to splices wires instead of connecting them directly.

• Avoid overstuffing boxes which can damage wires. Use multiple smaller boxes if needed.

• Label all wires and terminals so you know what they connect to.

• Check your work! Not energizing the panel until you've inspected the full system protects from overlooked hazards.

Saving Money on an Electrical Rewiring Project

Though rewiring is an involved project, there are ways to reduce costs:

• Buying supplies in bulk online can offer big savings on wire, outlets, breakers, and other parts.

• Have an electrician quote labor only, then provide specialty parts like the panel yourself at retail prices.

• Rewire room-by-room instead of the full house at once to spread costs over time.

• Ask the electrical inspector about DIY-permitted work in your area to avoid costly contractor markup on labor.

• Purchase refurbished or used parts from reputable suppliers when possible. Light fixtures, ceiling fans and service panels can all offer major discounts.

• Watch for sales on electrical supplies at big box stores, especially during off-peak seasons. Stock up on essentials when you see a bargain.

With the right planning, safety precautions, and cost-saving steps, you can tackle rewiring your home's electrical system yourself and save thousands over hiring an electrician. Just be sure to research thoroughly and follow codes to ensure the work is done properly. Though it's a major undertaking, the reward of updated, safe, adequate power throughout your home makes the effort well worth it.