Do Garage Outlets Need to Be GFCI?

Ground faults are a safety hazard in the garage setting, and to prevent serious injury, a device capable of managing the currents in outlets is necessary. Enter: ground fault circuit interrupters (GFCIs). 

Ground fault circuit interrupters (GFCIs) are designed to monitor incoming and outgoing currents in a wall outlet. They ensure that the current being delivered to the operator of an electrical device plugged into the outlet is no greater than the safe limit of five milliamperes (mA). 

Since they can prevent serious, even fatal, injury due to electrical shock, GFCI outlets are often required by electrical codes when it comes to home construction. However, there are some circumstances in which you may not need to install a GFCI outlet. 

What Are GFCI Outlets?

GFCI stands for “ground fault circuit interrupter.” GFCI outlets are designed in a manner so that they can break the circuit if there is an imbalance between incoming and outgoing currents. The primary purpose of a GFCI outlet is to prevent wiring and electrical devices from overheating, which can lead to shock injuries and burns.

How Do GFCI Outlets Work?

GFCI outlets are capable of continually comparing the amount of electricity flowing out of the outlet with the amount of electricity that is flowing into the outlet; this is so the system can immediately take action in the event of an electrical fault.

An electrical fault within a garage can more likely lead to a severe injury if it happens while you are operating a power tool. This electrical fault occurs when the return current is less than the value of the current being supplied, and the operator of the device will feel the excess current. 

If the current is greater than ten milliamperes (mA), then the operator will definitely feel a painful shock. Currents greater than 18 mA will lead to serious injury, potentially fatal.

GFCI outlets protect users from electrical shock. They ensure that the worst possible shock incurred from being exposed to electricity is a five mA current. At this level, a small shock will be felt, but it will not be painful. 

Do Garages Need GFCI Outlets?

GFCI outlets are required by the National Electric Code (NEC) to be installed in all outlets inside the home near a water source. (The International Residential Code (IRC) also requires this.) These codes have been updated only recently after years of only requiring GFCI outlets in locations near water, like bathrooms, laundry rooms, and kitchens.

Under most circumstances, garages do need GFCI outlets. However, you will not be required to install these types of outlets in locations that are not readily accessible. Examples of this include ceiling-mounted receptacles used for garage door openers.

You are also not required to install GFCI outlets on dedicated branch circuits used to power cord and plug appliances; this includes refrigerators and freezers. 

But, in any other case, GFCI outlets are mandated by code.

Why Are GFCI Outlets Required in Garages?

Ground faults are the root cause of more than 80% of all electrical equipment failures. These ground faults often happen as a result of worn insulation on the wire. Other risk factors include moisture, dust, and the age of the electrical appliances plugged in.

Moisture and dust are certainly found in abundance in garages. There is also a good chance that you have some old appliances plugged into garage outlets as well. Not installing GFCI outlets in the garage space poses a significant risk of a ground fault, and there are few better ways to ensure that you and your electrical equipment are kept safe.

How Do I Change an Outlet to a GCFI Outlet?

Any outlets that are not GCFI outlets can easily be converted to be compliant with current electrical codes. The tools you will need to complete this task include a non-contact voltage tester, a slotted screwdriver, and a Phillips-head screwdriver (links to Amazon).

Here are the instructions for converting any outlet to a GCFI outlet:

  1. Turn off the electrical power to the circuit serving the outlet that you plan on changing. To do this, switch off the corresponding breaker in the breaker box. You can use a non-contact voltage tester to ensure that the power is off.
  2. Use a slotted screwdriver to remove the cover plate from the preexisting outlet. Insert the voltage tester into each screw terminal to ensure that there is no voltage present.
  3. Pull the outlet far enough out of the electrical box so that you can loosen the screws holding the black and white electrical wires from their respective terminals.
  4. Loosen the screw holding the bare ground wire to completely remove the outlet.
  5. Pick up the GCFI outlet. Wrap the bare end of the white electrical wire around the silver screw neutral on the GFCI outlet marked “Line.” Wrap the bare end of the black electrical wire around the brass screw terminal. Wrap the bare ground wire around the ground terminal screw.
  6. Carefully push the wires now attached to the GFCI outlet back into the receptacle with the socket. Install the cover plate back over the device. 

GFCI Outlet Adapters

Older homes will likely not have GFCI outlets as these are a relatively recent innovation in home construction, so you’ll likely need to have them installed throughout the home and garage to stay up to code. However, rather than replacing the outlet completely, you can safely use an outlet adapter. The adapter can be plugged into a grounded socket to provide safety from ground faults.

This is an affordable option for those who want to bring their garage into compliance with modern electrical codes, and is not as invasive as having to do any form of electrical work. You can find outlet adapters, like this one (link to Amazon), online for a low price. 

How to Test a GFCI Outlet

You are encouraged to regularly test your GFCI outlets to ensure that they are working correctly. This is particularly true if this is not an outlet that you installed yourself. If a socket has not been used in quite some time, then a quick test would not be a bad idea.

The test can be performed in four easy steps:

  1. Start by pushing the “RESET” button on the receptacle.
  2. Plug a light into the receptacle with its own “ON/OFF” switch and turn the light ON.
  3. Press the “TEST” button that is located on the GFCI receptacle.
  4. Push the “RESET” button once again; if the outlet is functional, the light will turn on.

(Source: On the Gulf Home Inspection)

Why Is My GFCI Outlet Not Working?

There are a variety of potential causes for a malfunctioning GFCI outlet. Refer to an official instruction manual or licensed professional to resolve an issue with the GFCI outlet. Many times it will be an easy fix, but there could be problems both upstream and downstream currents in the socket worth getting checked out. 

Here are some possible reasons that your GFCI outlet is not working:

  • There’s a ground fault occurring at a regular outlet that isn’t working.
  • The GFCI is either open or tripped.
  • No power is reaching the GFCI outlet.


Regulations set forth by the National Electric Code (NEC) and the International Residential Code (IRC) state that GFCI outlets shall be used when the plug is within six feet of a water source. Exceptions include outlets for appliances like freezers and refrigerators and also ceiling installations for garage door openers.

GFCI outlets are indeed needed for areas that are going to provide electricity for outdoor power tools. Not following the guidelines set by the NEC and IRC poses a significant risk for an electrical shock if there happens to be a ground fault. GFCI outlets can limit the excess current to a rating of five milliamperes, which is not enough to lead to a severe injury.

However, you do not necessarily need to replace old outlets with GFCI outlets completely. There are plug-in adapters (link to Amazon) that will have a similar effect; this is an alternative method adequate for residential garages with the old style of outlets.