Adding an Electrical Outlet in the Middle of a Run

Adding an electrical outlet in the middle of an existing circuit run can provide much-needed access to power in inconvenient locations. With proper planning and adherence to electrical codes, this project can be accomplished safely by a knowledgeable DIYer.

Reasons for Adding an Outlet Mid-Run

There are several scenarios where installing an outlet mid-run is desirable:

  • Converting a room into a home office or workshop where more receptacles are needed.
  • Powering a new appliance or device located far from existing outlets.
  • Reducing reliance on extension cords and power strips.
  • Updating an older home with too few outlets.
  • Providing outlets for holiday lighting and decorations.

The key is determining if the electrical load allows an additional outlet to be safely added.

Electrical Load Considerations

  • Most standard residential circuits are rated for 15 or 20 amps.
  • Adding an outlet mid-run splits the circuit, reducing available power for existing outlets.
  • Major appliances like refrigerators and AC units require their own dedicated circuits.
  • Smaller lights and devices can often share a residential circuit.
  • Exceeding the circuit load capacity can trip breakers or result in overheating.

A qualified electrician can calculate the existing load and determine if there is sufficient capacity for the new outlet.

DIY Installation Overview

For a DIYer, adding an outlet mid-run involves:

  • Turning off power at the circuit breaker.
  • Cutting into the drywall to access the wires.
  • Installing an electrical box securely in the cut-out.
  • Splicing the circuit wires to feed the new outlet.
  • Patching the drywall once wiring is completed.

Safety gear like glasses, gloves, and a face mask should always be worn during electrical work.

Step-by-Step Installation Guide

Follow these key steps to safely add an outlet mid-run on an existing circuit:

1. Turn Off the Power

The circuit must be de-energized! Turn off the correct breaker and double check with a non-contact voltage tester.

2. Cut the Drywall

Outline the box location and make neat cut-outs in the drywall to access the wiring. Avoid plumbing, wiring, and materials like fireblocks.

3. Install the Electrical Box

Choose a plastic retrofit box designed for mid-run installs. Secure it to a stud according to codes for support.

4. Splice the Wires

Carefully open the Romex jacket and splice pigtails to the circuit hot and neutral wires. Secure new and existing wires properly in wire nuts.

5. Connect the Outlet

Connect the black (hot) and white (neutral) wires to the new receptacle. Don’t forget the ground wire!

6. Secure the Outlet

Mount the receptacle securely into the electrical box. Make sure wires are neatly positioned and have slack.

7. Patch Drywall

Fill cut-out gaps with backing material before patching holes with drywall compound and retaping for a seamless fix.

8. Re-Energize and Test

Turn the power back on at the breaker. Verify safe operation of the new outlet before use.

Common Mistakes to Avoid

  • Touching wires when the circuit is live. Always turn off power!
  • Choosing the wrong breaker and working on an energized circuit.
  • Loose wire connections prone to arcing faults.
  • Exceeding the amperage rating and overloading the circuit.
  • Failing to connect the grounding wire. This provides an important safety path.
  • Not securing the electrical box adequately within the wall.

Consult an electrician if you are unsure about any part of the process or wiring methods.

Electrical Codes

Electrical work must adhere to local building codes. Key requirements include:

  • Only splicing wires inside approved electrical boxes with secured clamps.
  • Using the correct wire gauge for the breaker amperage rating.
  • Proper outlet spacing based on room size and usage.
  • GFCI protection for outlets near water sources.
  • Tamper-resistant receptacles for home child safety.

Verify your local regulations before starting any electrical project.

Further Considerations

  • For frequent heavy loads like large tools, a new dedicated 20 amp circuit may be preferable to a shared 15 amp circuit.
  • Consider including a switch for any outlets controlled independently.
  • Having an electrical permit and inspection provides an extra layer of safety.
  • Hiring a professional electrician ensures proper installation and workmanship.
  • Only splicing similar wires – hot to hot and neutral to neutral.

Upgrading an electrical panel may be necessary if all circuits are already fully loaded.

FAQ about Adding Outlets Mid-Run

Here are answers to some frequently asked questions about adding an outlet in the middle of a circuit:

How much does it cost to add an outlet mid-run?

The costs for parts like the box, wiring, and receptacle will be $10-$30. Hiring an electrician will involve labor costs of $50-$120 per hour plus this material cost.

Can I tap into the existing wires or do they need to be replaced?

The existing wires can be tapped by splicing into them as long as there is enough capacity on the circuit to support the new outlet.

Do both outlets before and after need GFCI protection?

Yes, any outlets added mid-run will need GFCI outlets if that circuit has GFCI protection at the start.

What amperage breaker should the new outlet be on?

Match the amperage of the existing circuit, which is commonly 15 or 20 amps in a standard home.

Can I install this outlet myself without an electrician?

If you understand electrical systems and can follow all safety codes, a DIY install is possible. Most homeowners prefer hiring a pro.

Will this addition reduce power to my existing outlets?

Possibly, if the total load exceeds the circuit capacity. This is why a load calculation is important.


Adding an electrical outlet mid-run in an existing wall is a project a homeowner can take on with proper planning and preparation. The most important steps are turning off power, installing the box securely, splicing wires correctly, and making sure circuits are not overloaded. Following basic electrical safety and building codes helps ensure a safe installation. For larger projects or complications, hiring a professional electrician is recommended for expertise and compliance with regulations. With some electrical knowledge and attention to detail, an outlet can be added mid-circuit to provide convenient access to power anywhere inside the home.