Permit Required
Kentucky law (KRS 198B.650โ198B.689) requires a permit for every HVAC installation and replacement, including 1-for-1 equipment swaps. There are no size or value thresholds that exempt a project.
The Law: Why Kentucky is Different
Most states leave HVAC permitting to local jurisdictions โ counties and cities set their own rules. Kentucky took a different path. On January 1, 2011, the state became the first in the nation to implement a mandatory statewide HVAC permitting and inspection program through the Department of Housing, Buildings and Construction (DHBC), Division of HVAC.
The governing statutes are KRS 198B.650 through 198B.689, and the implementing regulation is 815 KAR 8:070. The practical result: no matter what county you live in, a permit is required before HVAC work begins.
However, there is an important wrinkle: some Kentucky counties administer their own HVAC permitting program with local inspectors. If you live in a county with a local program, you apply to the county โ not the state. If you live in a county without a local program, you apply directly to the Kentucky DHBC.
What Projects Require a Permit in Kentucky?
A permit is required for:
- New HVAC installations in any building where no system previously existed
- Replacement systems โ even a 1-for-1 swap of the exact same equipment model
- System additions โ adding a second zone, additional air handler, or supplemental heat
- Mini-split and ductless system installations (mechanical permit required; electrical permit usually also required)
- Ductwork alterations that extend or significantly modify an existing duct system
A permit is generally not required for:
- Routine maintenance (filter changes, coil cleaning, annual tune-ups)
- Replacing individual components without altering the system (capacitor, contactor, blower motor)
- Adding refrigerant to an existing, permitted system
Important: Water Heater Permits Are Separate
Kentucky HVAC permits do not cover water heaters. Water heater permits are handled by the Kentucky Division of Plumbing. In Boone County, contact 859-331-8228. Do not confuse the two departments.
Who Can Pull an HVAC Permit in Kentucky?
Kentucky HVAC permits may only be issued to two categories of applicants:
- A licensed Kentucky HVAC Master Contractor โ the contractor or company performing the work must hold a current Kentucky Master HVAC License issued by the DHBC. A Journeyman license alone is not sufficient to pull a permit.
- A homeowner, under the Homeowner Exemption โ with significant restrictions (see below).
The Homeowner Exemption: One Permit Every Five Years
This is one of the most frequently misunderstood rules in Kentucky HVAC permitting. Kentucky law does allow a homeowner to pull their own HVAC permit, but with these specific conditions:
- The work must be performed at the homeowner's legal residence (not a rental property, not a vacation home)
- The work must be personally performed by the homeowner โ you cannot hire an unlicensed person using your homeowner permit
- Only one homeowner HVAC permit may be issued to an individual within any five-year period
- Refrigerant (freon) installation must still be performed by a licensed HVAC technician โ this is a separate requirement under EPA Section 608 and cannot be waived by the homeowner exemption
In practice, the homeowner exemption is rarely used. Most homeowners who hire an HVAC contractor have the contractor pull the permit. The exemption exists primarily for homeowners who are skilled trades workers themselves and want to do their own work.
Local Program vs. State Program: Which Office Do You Call?
This is the most confusing aspect of Kentucky HVAC permitting. The DHBC operates the state program, but many high-population counties have their own approved local HVAC inspection programs. If your county has a local program, all permitting and inspections are handled locally โ the state does not get involved.
| County | Program Type | Where to Apply | Phone | Online Portal? |
|---|---|---|---|---|
| Boone County | Local Program | Boone County Building Dept, 2950 Washington St, Burlington | 859-334-2218 | Yes โ online portal available |
| Campbell County | Local Program | Campbell County Building Dept | 859-292-3840 | Check county website |
| Kenton County | Local Program | Kenton County via city jurisdictions | 859-392-1400 | Varies by city |
| Jefferson County (Louisville) | Local Program | Louisville Metro DPDS, 444 S 5th St | 502-574-3321 | Yes |
| Fayette County (Lexington) | Local Program | Lexington-Fayette Urban County Building Inspection Office | 859-258-3770 | Yes |
| All other counties | State Program (DHBC) | SmartGov portal: dept-hbc-ky.smartgovcommunity.com | 502-573-0365 | Yes โ SmartGov |
HVAC Permit Fees in Kentucky
Fees vary between local and state programs. Here are verified figures for the most common project types:
| Jurisdiction | Residential Replacement (1 unit) | Each Additional Unit | New Installation |
|---|---|---|---|
| Boone County | $105 | $50 | $105 + plan review |
| Louisville Metro | Varies by valuation | โ | Varies |
| State DHBC Program | See DHBC fee schedule (815 KAR 8:070) | โ | Varies |
Payment methods vary. Boone County accepts cash, checks payable to "Boone County Fiscal Court," Visa, and Mastercard. The state SmartGov portal accepts credit cards. Call ahead to confirm current accepted payment methods at your local office.
What the HVAC Inspection Covers
Kentucky requires different inspections for new installations versus replacements:
For new HVAC installations: Two inspections are required โ a rough-in inspection (before framing is insulated) and a final inspection when installation is complete.
For replacement systems: Only a final inspection is required when the installation is complete. This is typically a 20โ30 minute visit.
During the final inspection on a residential replacement, the inspector will check:
- Equipment data plates โ confirming the installed unit matches the permit application
- Refrigerant line set installation and insulation
- Electrical disconnect and wiring at the outdoor unit
- Flue venting for gas furnaces (clearances, material, slope, termination)
- Condensate drain line routing and termination
- Filter slot accessibility and correct size
- Thermostat wiring
- Permit card posted at job site
Emergency Installations
Boone County (and most Kentucky local programs) accommodate emergency HVAC replacements โ for example, when a system fails in extreme heat or cold. If your system fails on a weekend or holiday, you may proceed with the installation, but you must:
- Call the building department immediately (even if you leave a message: 859-334-2218 or 859-334-3979 for Boone County)
- Apply for the permit on the very next business day
- If the permit is not filed by close of business on the next business day, a double permit fee will be assessed
What Happens If Work Is Done Without a Permit?
Kentucky building departments take unpermitted HVAC work seriously. The standard consequences include:
- A fine levied in addition to the original permit fee (amounts vary by county; Boone County publishes a violation schedule)
- Required retroactive permitting with a possible full inspection โ which may require exposing ductwork or equipment already installed
- Complications at resale: home inspectors routinely check permit records. Unpermitted HVAC work is a common reason deals fall through
- Insurance coverage issues: if your HVAC-related claim (e.g., water damage from a condensate line) is traced to unpermitted work, your insurer may deny the claim
County-Specific Guides
For homeowners in Northern Kentucky and the greater Louisville and Lexington areas, we have detailed guides for the most common jurisdictions:
- Boone County, KY โ Full permit guide with online portal instructions
- Campbell County, KY โ Local program details and contact info
- Kenton County, KY โ City-by-city breakdown (Covington, Erlanger, Florence)
- Jefferson County (Louisville Metro) โ Metro DPDS process and online portal
Pro Tip for Homeowners
Before work begins, ask your HVAC contractor to show you the permit application receipt or permit number. In Kentucky, the permit card must be posted at the job site during the installation. A contractor who resists providing proof may not be pulling the required permit.