· by Michael Blair, Nashville's Electrician
The short version we give homeowners: a GFCI is the shock device and an AFCI is the fire device. Which rooms need which depends on the edition of the electrical code that governs the house, and around Nashville there are two in play. Metro Nashville’s adopted codes list names the 2023 National Electrical Code, adopted with local amendments, while the State Fire Marshal’s list of currently adopted codes names the 2017 edition. The question usually surfaces when someone starts a remodel.
Where is GFCI protection required?
We start wherever water and power share a room: bathrooms, kitchen counters, the laundry, the garage, an unfinished basement or crawl space, and every outdoor receptacle. On a service call those are the outlets we test first, pressing the test button on each GFCI and checking that the outlet actually goes dead.
The exact list of required locations comes from whichever code edition applies, so a house wired decades ago may not match what an inspector expects on new work. When a job touches a kitchen appliance circuit or the disconnect for an outdoor HVAC unit, we check that circuit’s protection against the right edition before we quote it, and our lighting and outlet work is priced with that check built in.
Where AFCI belongs
Tennessee’s state code is clearest about where AFCI is not mandatory. The State Fire Marshal’s adopted codes page takes the 2017 National Electrical Code with AFCIs made optional for bathrooms, laundry areas, garages, unfinished basements used for storage or work, and circuits dedicated to refrigeration equipment. Read the other way round, that leaves the finished rooms people live and sleep in, and on a job under the state code that is where we plan for AFCI.
Whether Metro’s local amendments carry the same exceptions is something we confirm with Metro Codes before telling a Davidson County customer which rooms need it. When an AFCI starts tripping, we trace the cause rather than swap the breaker, and our post on a breaker that keeps tripping walks through how arc faults and ground faults differ.
- Metro Nashville: 2023 National Electrical Code, with local amendments
- Tennessee state list: 2017 National Electrical Code
- AFCI optional on the state list: bathrooms, laundry, garages, unfinished basements, refrigeration circuits
- Our rule: confirm the edition for the address before quoting
What triggers the requirement on a remodel?
In Davidson County, the trigger we watch is the permit. Metro’s page on renovating a single-family residence says interior renovations go through Metro Codes, that the permit triggers the required inspections, and that relocating a fixture, switch or outlet is on its list of work needing a rehab permit.
That page also asks for a scope of work listing each of those activities, so we write ours around the circuits we will actually alter, extend or replace. It says nothing about how far a change pulls an existing circuit up to the 2023 edition, so where that affects the price we ask Metro Codes first. Where the state does the inspecting, its electrical and residential inspection section issues the permits and performs the inspections under Tennessee’s adopted electrical code. Even a straight receptacle swap in a bathroom or kitchen is a point where we check whether that spot is protected.
Doing it without a rewire
For GFCI, we try the device route before anyone opens a wall. Our usual move is a GFCI receptacle at the first outlet on the run, with the outlets after it wired from its protected side; then we trip it, check that each of those outlets goes dead, and label them so the reset is easy to find.
For AFCI we start at the panel and look for an AFCI breaker made for that panel. On a very old panel we sometimes cannot find one, and that is when replacing the panel becomes part of the conversation. If you want the protection in your house checked against the edition that applies at your address, ask us for a free estimate.
Sources
- Metro Nashville Codes and Building Safety, Adopted Codes for Metro Nashville (updated July 28, 2025) — Metro adopted the 2023 National Electrical Code and 2024 International Residential Code with local amendments
- Tennessee State Fire Marshal’s Office, Currently Adopted Codes and Code Adoption History — State list adopts the 2017 NEC with AFCIs optional for bathrooms, laundry areas, garages, unfinished basements and refrigeration circuits
- Metro Nashville Codes, Building Permits Central: I Want to Renovate a Single-Family Residence — Interior renovations need a Metro permit that triggers inspections; relocating a fixture, switch or outlet needs a rehab permit; scope of work lists the activities
- Tennessee State Fire Marshal’s Office, Electrical, Residential and Marina Inspection section — The section issues permits and performs inspections to enforce Tennessee’s adopted electric code
FAQ
Where GFCI and AFCI Protection Is Required — questions
Do I have to bring my whole house up to current code when I remodel?
There is no single answer we can quote for every house. Metro’s renovation permit asks for a scope of work that lists the activities in the project, and relocating a fixture, switch or outlet is on its list of work that needs a rehab permit. Whether a given change brings other circuits up to the current edition is a question we put to Metro Codes before we price the job. An open wall is still the easiest time to fix anything else nearby, so it is worth asking what else is within reach.
Why does my AFCI breaker keep tripping?
We cannot tell from here, and that is the point: a repeat trip is something to trace. We test the circuit, note what is running when it trips, and check the wiring behind it before anyone talks about the breaker. We do not swap an AFCI for a standard breaker to make the trips stop, because that only takes away the protection the circuit was given.
Can one GFCI protect several outlets?
Often, yes. When we fit a GFCI receptacle at the first outlet on a run, we wire the outlets after it from its protected side, then trip it and check that each of them goes dead. We label the protected outlets so the reset button is easy to find. Whether that arrangement satisfies the code for a given room depends on the edition that applies to the house.
What is the purpose of a GFCI?
Protecting people from shock. We call the GFCI the shock device and the AFCI the fire device, which is why GFCIs go where water and power meet: bathrooms, kitchen counters, laundry rooms, garages, unfinished basements, crawl spaces and outdoors. On a service call we press each test button and confirm the outlet really goes dead.