Code basics for anyone planning to add a room or finish a garage.

By Electric · May 20, 2026 · 4 min read

When you're adding a room, a garage, or a second story to your Texas home, the electrical work has to meet current code. That's not optional, and it's not something you figure out as you go. Texas follows the National Electrical Code with state amendments, and your local authority having jurisdiction (usually your city or county) enforces those rules. Get the wiring wrong and you're looking at failed inspections, insurance problems, or worse. Get it right from the start, and your addition is safe and legal.

The Permit and Inspection Process

You need an electrical permit before any wire goes in. This isn't a suggestion. Your contractor or electrician pulls the permit, which costs money based on the scope of work, and the local inspector schedules rough-in and final inspections. The rough-in happens after walls are framed but before drywall goes up, so the inspector can see all the wiring runs, boxes, and connections. The final inspection happens after everything is closed up and the system is energized. In most Texas jurisdictions, you can't get a certificate of occupancy or pass a final home inspection without electrical sign-off. If you try to do this work without a permit and get caught, the city can require you to rip out the work and redo it properly at much higher cost.

Panel Capacity and Service Upgrades

Your home's electrical panel has a maximum capacity, usually 100, 150, or 200 amps. A major addition, especially one with air conditioning, electric heat, or a large kitchen, can push you over that limit. The code requires that the total calculated load of all circuits and fixed appliances never exceeds the panel's rating. If your addition needs more capacity than you have available, you'll need a service upgrade. That means a new meter, new main breaker, and sometimes a new panel entirely. It's expensive, but it's mandatory. An electrician can run the load calculation for you and tell you whether an upgrade is necessary before you start framing.

Circuit Requirements for Different Rooms

The code spells out how many circuits and outlets you need based on room type and size. A bedroom needs at least one 15-amp general-purpose circuit for every 500 square feet, plus a dedicated 20-amp circuit for each bathroom. Kitchen and laundry areas have their own rules: kitchens need at least two 20-amp small-appliance circuits, and a laundry area needs one dedicated 20-amp circuit. Living areas need outlets spaced so no point on the wall is more than 6 feet from an outlet. Bathrooms need a GFCI-protected outlet within 3 feet of the sink. These aren't negotiable minimums. The code assumes you'll use your space, and the circuits are sized to handle that realistic load.

Grounding, Bonding, and Safety Equipment

Every circuit in your addition must have a properly sized ground wire running back to the panel. In new construction, that ground wire is usually green or bare copper. All metal boxes, conduit, and equipment must be bonded together and connected to ground. If you're adding a bathroom, every outlet within 6 feet of the sink must be GFCI-protected. If you're adding a garage, outdoor outlets, or a wet location, GFCI protection is required. Arc-fault circuit interrupters (AFCIs) are required on most circuits in bedrooms and living areas to protect against electrical fires caused by damaged wiring. These devices are code-mandated safety equipment, not upgrades.

Wire Sizing and Conduit Runs

The wire size has to match the circuit breaker and the distance it travels. A 20-amp circuit typically uses 12-gauge wire, while a 15-amp circuit uses 14-gauge. If you run wire a long distance from the panel, you may need to go up a gauge to account for voltage drop. All wire must be protected inside walls, either by running it through conduit, running it in approved cable (like Romex), or running it in a chase. Exposed wire in a garage, basement, or crawlspace needs to be in conduit or protected from physical damage. The code is strict about this because damaged insulation is a fire and shock hazard.

Working with Your Electrician

The best way to stay compliant is to hire a licensed electrician who knows Texas code and your local jurisdiction's amendments. They pull the permit, do the work to code, call for inspections, and make sure everything passes. If you're doing some of the work yourself, you still need a licensed electrician for certain parts, like the connection to the main panel. Don't assume that what worked in your original house will work in the addition. Code changes, jurisdictions have different rules, and the addition has to meet current standards, not old ones.

Call Electric Connection today to discuss your addition project. We'll walk you through the code requirements, tell you what upgrades you'll need, and make sure your new space is safe and legal from day one.

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