This is one high-level DIY that most homeowners should leave to a pro
Electrical systems are complex networks that power the lights, outlets, and appliances in your home. It's not easy to build one from scratch, and it’s crucial to know a lot about electrical codes, safety regulations, and how all the parts fit together to make sure your home's power is delivered safely. Although it might be possible to do it yourself, this DIY requires advanced knowledge and experience with electrical work, as well as careful planning and execution to avoid serious safety hazards. If you don’t have the proper skills and training, it’s best to invest in a local electrician to ensure your home’s wiring system is safe and compliant with local building codes. This guide explains how to wire a house and when to call an electrician.
Before beginning the wiring process, it’s essential to create an electrical plan for the placement of outlets, switches, and light fixtures, as well as the location of the main electrical panel. You should also consider the number of circuits you’ll need, and calculate the electrical load that your home requires. This will help you determine your electrical service needs and the types of wires and breakers to pick up. Be sure to carefully review local building codes and regulations to ensure your plan is safe and up-to-code.
You can use a pencil to mark the location on either side of the open wall space where they will go, or write directly on the wall if the drywall is not yet installed. Mark each box as either a duplex receptacle (dual outlet), single switch, GFCI, three-way switch, or light fixture. Use initials or electrical symbols for easy reference.
To ensure that your electrical system meets local building codes and safety standards, review your electrical plan with a licensed electrician.
The main electrical panel is where the power from the utility company enters your home and gets distributed to the various circuits around the house. To install it, shut off the power to your home at the meter or power main. Then, mount it in a location that follows local building codes and regulations.
Place each electrical box on your home’s wooden frame to determine its location and height. Measure each wall with a tape measure and use a level to ensure everything is flush. Standard heights for outlets are 12 inches, and the proper height for light switches should be 48 inches from the floor. Mount your box into the exposed wooden frame, placing a 2x4 behind so it juts forward enough to allow sufficient space for the drywall and window frames.
Next, drill holes through the wall studs to run electrical cables through and around the room. Holes should be a minimum of 3/4 inch in diameter and at least 1 1/4 inch away from the back of the stud or the wall. This helps ensure that the cables will run through the center without touching any of the surrounding walls.
Once the electrical panel and boxes are installed, begin running electrical wire and conduit throughout the house. Make sure to follow electrical color codes for hot, neutral, and ground wires. Again, if you’re not extremely well-versed in electrical wiring, consider hiring a professional electrician to ensure everything is up to code.
Start by running the conduit from the panel to the location of each outlet, switch, and fixture. Next, pull the wires through the conduit, ensuring there are no kinks or bulges. While a single wire can be threaded by hand, you may need to use needle-nose pliers to push and pull multiple cables through.
When running electrical wire and conduit, always follow local building codes and safety standards. For example, you should never run electrical wires through the same holes as plumbing or gas pipes. It’s best to consult with a local electrician to ensure the safety of your home’s wiring setup.
When you reach each circuit or switch box, cut the cable to fit, leaving at least 12 inches of extra length to avoid cutting it too short. Secure wires to wall studs or other surfaces with cable staples. Strip the last section of sheathing, exposing roughly 2 inches of the wires. Use wire covers to keep the ends safe until installation is completed.
Take the exposed wires and route them to the main circuit panel, connecting them to their corresponding circuits in the panel. It’s highly advisable to hire a professional electrician for this last step. Leave around 5 feet of extra cable to make it easier for your electrician to connect the cables to the panel.
Thread the cables through the pre-cut holes in each electrical box and staple them roughly 10 inches from the box against the wall studs for security. Strip the wires so they’re ready to connect to each circuit and switch. Use wire covers to keep the ends protected until installation is completed.
Once you've completed the wiring, group and label the wires appropriately. Using a marker and electrical tape is an effective method for this task, or you can use wire labels or zip ties. Proper grouping and labeling allow you to easily identify which wires belong to which devices such as overhead lighting, outlets, or light switches. This will make it a lot easier to install your fixtures, as well as troubleshoot and make any necessary changes to the wiring in the future.
Once you’re sure you’re finished with wiring, finish your drywall. Then, install your electrical outlets, light switches, and fixtures. Make sure to install GFCIs wherever there's moisture, such as in your bathroom, laundry room, and kitchen.
Electrical projects—especially complex ones such as rewiring your home—should more often than not be left to the pros. If you have prior experience in electrical work and are well-versed in electrical safety and confident in your abilities, then you might be able to do it yourself. However, it's essential to consider the level of complexity of the project and the risks involved. Poorly done electrical work can cause electrical fires, electrical shocks, and other safety hazards, which can put your family and property at risk.
Additionally, DIY wiring may not meet local building codes, which can result in fines and leave you unable to sell your home until the issues are fixed. It can also void your homeowner’s insurance in the event of an injury or accident. For these reasons and more, it’s always best to seek the expertise of a professional to keep your home and family safe.
Hiring a professional electrician to wire a house costs anywhere from $1,500 to $10,000 or more depending on the size and complexity of the project. Most professional electricians charge $50 to $100 per hour. While the extra expense is significant, it’s worth it to ensure the safety of your home’s electrical system.
A good estimate for wiring a house is to use one foot of wire per square foot of living space. However, this does not account for any detached structures like a garage or shed, which require additional wiring. It's always best to consult with a licensed electrician who can provide a more accurate estimate for the amount of wire you'll need for your home based on its unique features and electrical requirements.
Choosing between 12- or 14-gauge wire for your house depends on the electrical requirements of the circuit. A 12-gauge wire is thicker and can handle more power, making it better suited for devices such as kitchen appliances, air conditioning units, or electric heaters.
A 14-gauge wire is thinner and can handle less electrical current than a 12-gauge wire. It's ideal for circuits with lower power requirements, such as lighting or general-purpose outlets in bedrooms or living rooms.
While there is technically no limit to the number of outlets you can have on a 15-amp circuit breaker, a good guideline is to have one outlet per 1.5 amps, up to 80% of the circuit breaker's capacity. This means a maximum of eight outlets for a 15-amp circuit. It's important to consider the electrical load of each outlet, which can vary depending on the devices or appliances that will be plugged in. Overloading a circuit can cause tripped breakers or even electrical fires. Consulting with a licensed electrician can ensure the safety and compliance of your electrical system.
