LEARNING CENTER GENERAL
Do you need a plumbing permit in Louisville? (What requires one, what it costs, how long it takes)
The short answer
Usually, yes, but it depends on the job. A repair, unclogging a drain, fixing a running toilet, swapping a faucet or disposal for a new one in the same spot, doesn’t need a permit. A replacement or anything that alters the plumbing itself, a new water heater, a sewer line, a water line, a whole-house repipe, new gas piping, does. Kentucky also handles this differently than most states: the permit doesn’t come from Metro Louisville’s building department. It comes from the state’s own Division of Plumbing. For a single water heater replacement, the fee is a flat $50 under 815 KAR 20:050. Bigger jobs get scoped when we quote the work, since the fee depends on what’s actually being done. Either way, pulling the permit and scheduling the inspection that comes with it is part of doing the job right, and it doesn’t slow down the day we’re actually there.
Nobody calls us excited about a permit. It’s the paperwork part of the job, the thing that feels like it should be optional when all you want is your hot water back or that leak stopped. In Kentucky it genuinely isn’t optional for a lot of common jobs, and the rules here work a little differently than most homeowners expect. Here’s the honest version: what actually needs one, what it costs, who actually signs off on it, and whether it slows your job down.
What actually needs a permit, and what doesn’t
The line Kentucky draws is between a repair and an alteration. Fix what is already there, in the same spot, with the same connections, and you’re doing a repair. Replace it, move it, or add to the system, and you’re altering it, which is what pulls a permit into the picture.
Jobs that need a permit
- A water heater replacement Even a straight like-for-like swap counts, which surprises a lot of people. Kentucky requires a permit for a water heater replacement, gas or electric, and it comes with a fee. For a single water heater in one building, the fee is a flat $50 under 815 KAR 20:050. A repair, a new thermocouple or heating element, does not need one. The tank coming out and a new one going in does.
- A sewer line repair or replacement Digging up or relining the buried pipe that carries waste out to the street is exactly the kind of work Kentucky’s plumbing code is written to cover. We handle the paperwork as part of any sewer job, and the fee gets scoped to the size of the work rather than a flat number like the one for water heaters.
- A main water line replacement The line from your meter to your house is homeowner-owned, and replacing it needs a permit too. Once the new line is in and pressure-tested, the ground has to be restored, and the permit and the inspection that goes with it are part of that process, not an add-on afterward.
- A whole-house repipe Running new supply lines through a house, PEX or copper, is exactly the kind of system-wide alteration that needs a permit, the same as a sewer or water line does. It is a bigger job with more inspected work behind it, and we build the permit into the timeline when we scope it.
- Adding or resizing a gas line Running gas to a new appliance, or upsizing an existing line so a tankless water heater can pull enough gas, means new pipe and a permit to go with it. After any gas work, the system has to hold a pressure test and pass inspection before we turn the gas back on. That’s not us being cautious. That’s code.
Jobs that usually don’t
- Unclogging a drain or the main sewer line Snaking or hydro jetting a line that’s still structurally sound is maintenance, not alteration. Nothing about the pipe changes, so nothing needs a permit.
- Fixing a running toilet Usually a $10 flapper. You’re replacing a worn part inside a tank that stays right where it was, and that’s a repair, not an alteration.
- Swapping a faucet, toilet, or disposal like-for-like New fixture, same location, same connections. That’s a straightforward repair-level job in most cases, not the kind of change the permit rule is aimed at.
- Fixing a water heater’s thermocouple, element, or igniter Repairing what is already installed doesn’t trigger the permit rule. Only the tank itself getting replaced pulls Kentucky’s permit requirement in.
Who actually issues it (it’s not the city)
Here’s the part that catches people off guard. In most states, your city or county building department issues plumbing permits. Not in Kentucky. Plumbing permits here go through the state’s own Division of Plumbing, part of the Department of Housing, Buildings and Construction, not Louisville Metro’s local codes office. That’s true no matter where in Jefferson County the work is happening.
There’s a homeowner exception worth knowing. Under Kentucky law (KRS 318), a homeowner can pull a permit and do plumbing work on their own primary residence. A rental property doesn’t get that exception. If you own the house you live in, you can legally pull your own permit. If you’re a landlord, the work has to go through a licensed plumber, permit included. When we do the job, we pull it either way and you don’t have to think about it.
What it costs
For a single water heater replacement in one building, the fee is set and flat: $50 under 815 KAR 20:050. It’s one of the few plumbing permit fees in Kentucky that’s a round, published number, which is why we can quote it with confidence every time. Bigger jobs, a sewer line, a water line, a repipe, new gas piping, get scoped to the actual work, so we won’t print a made-up flat number here. What we will tell you is that it’s a real line item on a licensed quote, and if a quote you’re comparing doesn’t mention it at all, ask why.
Where skipping the permit actually costs you
We’ve seen all three of these play out, and none of them end well:
- Selling the house Kentucky requires a permit even for a water heater swap, and if the work was done without one, a buyer’s agent or a home inspector tends to find it eventually. It’s better to know now and get ahead of it than to have it surface during someone else’s inspection.
- A DIY job on a rental The homeowner permit exception only covers your own primary residence. Doing unpermitted work on a rental isn’t a gray area, it’s outside the rule, and it’s the tenant who’s living with whatever wasn’t inspected.
- An uninspected water heater The follow-up inspection isn’t busywork. It’s a second set of eyes confirming the gas, the venting, and the connections were done to code. Skipping the permit means skipping that check too.
Does the permit slow the job down?
Not in our experience. For a water heater, the install happens the day we’re on site, and the permit and inspection get handled around it. The inspection is scheduled separately, so it never leaves you without hot water. For a bigger job like a sewer line or a main water line, the permit needs to be in hand before we open the ground, so we pull it as part of scheduling the work rather than as a separate step you have to manage yourself. Either way, the paperwork runs alongside the job, not ahead of it, and you’re not the one chasing it down. Not sure whether your project needs one at all? Ask Goldie can walk you through it in a couple of minutes.
Common questions we get
Do I need a permit to replace my water heater in Louisville?
Yes. Kentucky requires a permit for a water heater replacement even when it’s a straight like-for-like swap, gas or electric. For a single water heater in one building, the fee is a flat $50 under 815 KAR 20:050. A repair, a thermocouple or a heating element, doesn’t need one. Only the tank replacement itself does.
Who actually issues plumbing permits in Kentucky?
The state, not the city. Plumbing permits go through Kentucky’s Division of Plumbing, part of the Department of Housing, Buildings and Construction, rather than Louisville Metro’s local building department. That’s true anywhere in Jefferson County, which is the opposite of how most states handle it.
Can I pull my own plumbing permit?
If you own and live in the house, yes. Kentucky law (KRS 318) lets a homeowner pull a permit and do plumbing work on their own primary residence. That exception doesn’t extend to rental property. A landlord needs a licensed plumber to pull the permit and do the work.
Does getting a permit slow down my plumbing repair?
Usually not. For a water heater, the install happens the day we’re there, and the follow-up inspection gets scheduled separately afterward, so it never leaves you without hot water. For a bigger dig job, the permit has to be in hand before we open the ground, so we build it into the scheduling rather than adding it as an extra step on top of the work.
What happens if plumbing work was done without a permit?
Nothing happens automatically, but it tends to surface at the worst time, usually when you’re selling the house and a buyer’s inspector or agent finds it. If you’re not sure whether older work in your home was permitted, we can take a look and tell you honestly where you stand before it becomes someone else’s discovery.
The next questions to ask
Not sure if your project needs a permit before anyone touches a wrench?
Ask Goldie walks you through what your specific job needs in a couple of minutes, permit included if it applies. Try it at goldenplumbingky.com/instant-estimate/