Timothy Thiele is an electrician who advises residential DIYers on how to make home installation projects safe and easy.

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Larry Campbell is an electrical contractor with 36 years of experience in residential and light commercial electrical wiring.
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A kitchen uses more electricity than any other room in the home, and the National Electrical Code stipulates that it should be amply served by multiple circuits. In a kitchen that uses electrical cooking appliances, this can mean it needs as many as seven or eight circuits. Compare this to the requirements for a bedroom or other living area, where a single general-purpose lighting circuit can serve all the light fixtures and plug-in outlets.

At one time, most kitchen appliances were plugged into ordinary general outlet circuits, but as kitchen appliances have become larger and larger over the years, it's now standard—and required by Building Code—for each of these appliances to have a dedicated appliance circuit that serves nothing else. In addition, kitchens require small appliance circuits and at least one lighting circuit.

Be aware that not all local Building Codes have the same requirements. While the NEC (National Electrical Code) serves as the basis for most local codes, individual communities can, and often do, set their own standards. Always check with your local code authorities on requirements for your community.

Kitchen Wiring in Older Homes

In older homes that have not had their wiring systems updated, it is very common for kitchen wiring to be undersized for the electrical demands of a modern kitchen. It is not uncommon, for example, for a kitchen to have only two or three circuits, and for basic appliances such as the refrigerator, dishwasher, garbage disposal to be powered by the same general-purpose circuit that powers the light fixtures and countertop receptacles. Generally speaking, older wiring systems are allowed to remain in place ("grandfathered in") when a kitchen undergoes modest remodeling efforts, such as simple replacement of appliances, flooring, and countertops. However, during major remodeling projects that require building permits, you may be required to bring your kitchen fully "up to code," and this very likely will require adding several electrical circuits.

Kitchen Wiring in Newer or Remodeled Kitchens

During new construction or major kitchen remodeling, the Building Code will likely require that you bring both the plumbing and wiring systems into alignment with the current Code requirements. This often involves adding electrical circuits and adding GFCI and/or AFCI protection. GFCIs have long been required in kitchens, but AFCI protection is a more recent addition.

AFCI protection: Beginning with the 2014 National Electrical Code revision and extended in the 2017 revision, a special type of circuit protection became required for many circuits in the home, including the kitchen. Known as AFCI (arc-fault circuit interrupters), these devices are designed to sense sparking (arcing) that occurs when electricity jumps between faulty wire connections. AFCIs shut down the current flow before a fire can occur. GFCI protection, on the other hand, is about protecting against shock.

In kitchens, the best advice is to make sure that all 15-amp and 20-amp circuits have AFCI protection. While this can be provided by special AFCI outlets, it is more typically done by installing circuit breakers with built-in AFCI protection. It's important to note that AFCI protection is different than GFCI (ground-fault circuit interruption) protection, and it does not replace those requirements. Many kitchen circuits require both AFCI and GFCI protection. In these instances, an electrician may install combination GFCI/AFCI circuit breakers, or they may use AFCI circuit breakers in combination with GFCI outlet receptacles.

There is by no means consensus on the requirements for AFCI protection in a kitchen. Even within a single jurisdiction, different inspectors may have different interpretations of the requirements. In some areas, any circuit that is served by a plug-in receptacles or wall switches requires AFCI protection, while elsewhere, the requirement is for AFCI protection for all 15-amp or 20-amp circuits, even those serving only hardwired appliances. The only way to be sure is to consult your local authorities before doing any circuit work in a kitchen.

Adding the necessary AFCI protection must be done whenever circuit work is done in the home. A professional electrician may be obliged to add some form of AFCI protection whenever working on a kitchen circuit, even for work as basic as replacing a single outlet receptacle.

Here is a list of the required electrical circuits in new construction or a major kitchen remodel.


Dishwasher Circuit

The dishwasher circuit should be a dedicated 120/125-volt, 15-amp circuit. This 15-amp circuit is fed with a 14/2 NM wire with a ground. You may also elect to feed the dishwasher with a 20-amp circuit using 12/2 NM wire with a ground. Be sure to allow enough slack on the NM cable so that the dishwasher can be pulled out and serviced without disconnecting it—your appliance repairman will thank you.

Some electricians will wire a kitchen so the dishwasher and garbage disposal are powered by the same circuit, but if this is done, it must be a 20-amp circuit and care must be taken to make sure the total amperage of both appliances does not exceed 80 percent of the circuit amperage rating. Check with local code authorities to see if this is allowed. 

GFCI and AFCI requirements vary from jurisdiction to jurisdiction. Usually, the circuit does require GFCI protection, but AFCI protection may not be required, depending on the local interpretation of the Code.

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Garbage Disposal Circuit

Garbage disposals do the dirty work of cleaning up the messes after meals. When loaded down with garbage, they use a good bit of amperage as they grind up the refuse. A dedicated 15-amp circuit is required, fed by a 14/2 NM cable with a ground. You may also elect to feed the disposer with a 20-amp circuit, using 12/2 NM wire with a ground. This is often done when the local Code allows the disposal to share a circuit with the dishwasher. You should always check with your local building inspector to see if this is allowed in your locale. 

Different jurisdictions may have different requirements requiring GFCI and AFCI protection for garbage disposals, so check with your local authorities. Including both AFCI and GFCI protection is the safest approach, but because the GFCIs can be prone to "phantom tripping" due to motor start-up surges, professional electrician often omit GFCIs on these circuits where local codes allow it. AFCI protection is generally required since these circuits are operated by a wall switch and the disposal may be wired to plug into a wall outlet.