How to Extend Power Outlets in Your Garage

Electricity in a garage is often an afterthought, usually leaving you with a single outlet hidden behind a workbench or nowhere near your primary workspace. Adding new outlets doesn't require tearing into finished drywall or hiring an electrician if you utilize the surface-mount method. By using conduit to house your wiring, you keep the installation robust, compliant with code, and easily accessible for future modifications. Done well, this project transforms a cluttered workspace full of daisy-chained extension cords into a professional shop environment. The goal is to provide dedicated, reliable power where you actually work, rather than relying on cords that create tripping hazards and voltage drops. Follow these steps to ensure your garage is as capable as the projects you take on inside it.

  1. Identify Your Power Source. Locate the nearest existing outlet and identify its breaker in the main panel. Turn off the power and use a non-contact voltage tester to verify the power is dead before removing any cover plates.
  2. Plot the Conduit Route. Measure and mark the desired location for your new outlets on the wall. Use a level to draw a straight line from your existing junction box to your new outlet boxes to keep the conduit run plumb and level.
  3. Secure Junction Boxes. Secure the shallow metal or PVC surface-mount boxes to the wall studs using wood screws. Ensure the boxes are flush against the surface and aligned with your marked path.
  4. Install Protective Conduit. Measure the distance between your boxes and cut the electrical conduit to fit perfectly. Attach the conduit segments to the boxes using appropriate connectors and secure the conduit to the wall with pipe straps every 3 feet.
  5. Thread Electrical Wire. Feed new THHN wire—black for hot, white for neutral, and green or bare for ground—through the conduit using a fish tape. Leave at least 6 inches of excess wire extending from each box for connections.
  6. Wire the Outlets. Strip the insulation from the ends of the wires and secure them to the new outlet terminals: black to gold/brass, white to silver, and green to the green grounding screw. Fold the wires neatly into the box and screw the outlet into place.
  7. Test Before You Plug In. Install the cover plates, turn the breaker back on, and test each new outlet with a plug-in circuit tester. Verify that the polarity is correct before plugging in any tools.