Building permits, zoning and septic rules in Mercer County, Kentucky
50Index Score / 100 #107 of 120 in Kentucky
Mercer County, Kentucky requires a building permit for virtually every structure placed on property in the county or Harrodsburg, subject to limited exemptions1. Residential applications begin with Planning Commission review, where staff verify setbacks, use and placement before the Building Inspector reviews the plans2. The published residential fee is $0.20 per square foot, with a $75 minimum3.
At a glance
Building permit
Required for virtually all structures in Mercer County and Harrodsburg, subject to limited exemptions1
Zoning
Yes in Mercer County and Harrodsburg, with setback review and zoning inspections; Burgin is outside the joint operation and has no zoning ordinance or map452
Permit fee
$0.20 per square foot for residential work, with a $75 minimum3
Septic authority
Mercer County Health Department handles evaluations, permits and inspections678
Owner-builder exemption
A homeowner may personally perform permitted plumbing in the homeowner's own residence under state conditions; acting as the general building contractor remains unconfirmed9
RV and tiny-home living
Unconfirmed for unincorporated land; ask Planning & Zoning before buying10
Floodplain permit
State and local permits are required for development in an identified floodplain11
Water well
No owner application or fee, but a Kentucky-certified driller must do the work12
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Do you need a building permit in Mercer County, Kentucky?
Yes. Mercer County requires a building permit for virtually every structure placed on property in Mercer County or Harrodsburg, including homes, manufactured homes, additions, decks, garages, pools and accessory structures larger than 200 square feet1. Kentucky has adopted statewide building and residential codes based on the 2015 International Building Code and International Residential Code with Kentucky amendments1314. Mercer County's local ordinance adds permits, inspections and occupancy approval for covered single-family work151617. The residential building-permit fee is $0.20 per square foot, subject to a $75 minimum3. Concrete patios, driveways and fences under 6 feet are listed exemptions118. Agricultural structures are exempt only when used for agriculture in an agricultural zoning district on a tract larger than 10 acres; the principal dwelling remains subject to permitting19. A homeowner may personally perform permitted plumbing in a home the homeowner occupies or is building for personal residential use, provided the homeowner applies before work begins, files the required affidavit, follows the plumbing rules and has not received another new-home homeowner permit within the previous five years9. That rule does not waive the plumbing permit or establish that an owner may act as the general building contractor9.
Who is the Mercer County building department, and how do you reach them?
The Mercer County Building Inspector is at 109 Short St., Harrodsburg, KY 40330 and can be reached at (859) 734-3375 or buildinginspector@mercerky.com18. Office hours are 8 a.m. to 12 p.m. and 1 p.m. to 4:30 p.m.; permits and plan reviews are normally handled in the morning, while field inspections occur in the afternoon18. Applicants provide ownership information, plans, a site plan and other listed project documents20. Start with Planning & Zoning because staff verify use, setbacks and placement before the Building Inspector reviews construction plans and floodplain issues2. Covered construction proceeds through footer, foundation, framing, insulation and final building inspections16. Final plumbing, electrical or septic approvals must be complete before the final inspection is scheduled, after which the Building Inspector issues the Certificate of Occupancy17.
Does Mercer County have zoning?
Yes. Mercer County and Harrodsburg participate in joint planning and zoning, but Burgin does not participate and has no zoning ordinance or zoning map for property inside its city limits5. The commission is at 109 Short St., Harrodsburg, KY 40330 and can be reached at (859) 734-606610. Mercer County zoning staff verify the proposed use, setbacks and placement before a permit goes to the Building Inspector21. A preliminary zoning inspection checks setback compliance, and a final zoning inspection verifies use and size; neither inspection requires an appointment2. If a proposed location may encroach on a setback, the applicant may request an on-site inspection by the enforcement officer2. The county publishes district maps, but calls them general references and directs owners to commission staff for an official zoning determination22. We could not confirm the numeric setback schedule, minimum lot size, minimum dwelling size, lot coverage or height limits; ask the commission for the district rules on the parcel2110.
How do septic permits work in Mercer County?
The Mercer County Health Department handles local onsite sewage evaluations, permits and inspections623. The environmental and administrative line is (859) 734-2229, and the office is at 900 N. College St., Harrodsburg, KY 4033024. A site evaluation comes before the permit, and the permit must be obtained before construction of any part of a new or altered system8. A certified installer must follow the evaluation unless the homeowner obtains a homeowner permit from the local health department8. Every installed, constructed, altered or repaired system requires inspection by a certified inspector8. Only about 3.7% of Mercer County soils are rated without severe limitations for a conventional drain field, so make the evaluation an early purchase contingency25.
Can you live in an RV or tiny home on your land in Mercer County?
We could not confirm a temporary or permanent RV, park-model or tiny-home occupancy rule for unincorporated Mercer County; ask the Greater Harrodsburg/Mercer County Planning & Zoning Commission about the parcel before buying10. Within Harrodsburg city limits, a travel trailer or recreational vehicle may not be used for permanent habitation, while temporary habitation requires a conditional-use permit from the Board of Adjustments & Appeals26. That Harrodsburg rule does not answer the question for unincorporated land. A statewide rule allowing temporary sleep in a lawfully parked vehicle on a public road, street or parking lot for less than 12 hours likewise does not authorize long-term RV living on private property27. For a tiny home, ask Planning & Zoning to confirm the allowed use, setbacks, dwelling-size standards and whether the design will be treated as a site-built, manufactured or recreational unit10.
What are the steps to build a home in Mercer County?
Ask the Greater Harrodsburg/Mercer County Planning & Zoning Commission to verify the parcel's district, allowed use, setbacks and placement; request an on-site inspection if the proposed location may encroach on a setback222.
For land outside Harrodsburg, obtain the Mercer County Health Department septic evaluation; inside Harrodsburg, provide copies of paid water and sewer tap fees before final inspection28.
Gather the ownership information, plans, site materials and other documents listed for the application20.
Resolve driveway access. A new or additional farm or single-family driveway involving a state highway right-of-way requires written application to the Department of Highways District Engineer29.
Submit the residential application and fee to the Mercer County Building Inspector3.
Obtain the state floodplain permit before construction in a floodplain and before the county issues its building permit30.
Complete the preliminary and final zoning inspections, the required construction inspections, and all final trade or septic approvals before obtaining the Certificate of Occupancy21617.
What should you check before buying land in Mercer County?
Check septic feasibility before treating a building site as settled: only 3.7% of Mercer County soils are rated without severe limitations for a conventional drain field25. Ask Planning & Zoning for an official district determination because the published maps are general references22. Check flood status because construction, demolition or renovation in a floodplain requires a state permit before work starts30. Confirm who controls the road before planning an entrance; a state-highway approach goes through the Department of Highways District Engineer29. Confirm whether the property is served by Harrodsburg water and sewer or needs a Health Department septic evaluation3132. A private well needs a Kentucky-certified driller but no separate owner application or fee12. Mercer County's effective property-tax rate is about 0.8%, the median annual tax bill is about $1,553, and typical home insurance is about $1,410 per year333435.
Watch-outs
Mercer County enforces setbacks through zoning review and inspections, but the numeric setback depends on the parcel's district; get the applicable distance from Planning & Zoning before locating a structure2110.
Kentucky's homeowner rule covers personally performed plumbing in the homeowner's own residence under stated conditions; it does not waive the plumbing permit or answer whether the owner may serve as the general building contractor9.
No county or state source in this guide answers whether Mercer County allows full-time RV or tiny-home living on private land; call the Planning & Zoning Commission before relying on any general assumption10.
Harrodsburg's ban on permanent RV habitation applies within city limits and does not establish the rule for unincorporated Mercer County26.
The farm-structure exemption applies to agricultural structures on agriculturally zoned tracts larger than 10 acres, not to the principal dwelling19.
Written October 7, 2026 from the rules quoted below, each taken from an official source and re-checked by an independent reviewer. This is research, not legal advice: rules change, so confirm with the office before you buy or build.
Mercer County highlighted among the Kentucky counties · colored by Index score
How Mercer County scores
Seclusion27100% ev.
Self-Sufficiency58100% ev.
Admin Boringness4190% ev.
Durability69100% ev.
Property Autonomy33100% ev.
Carry Cost81100% ev.
Evidence strength: 98%. This reports direct-source completeness and fallback use; it is separate from the score and is not a confidence interval. How it works →
$244kTypical home
0.8%Property tax
$5,326Land / acre
49.8"Annual rain
2.2% of yrsSevere drought
6.9 / yr (+6.5)Mid-century 100°F days
12.8 daysMid-century dry spell
2.05" (+6.3%)Mid-century 1-day rain
1.83×Wildfire change factor
100%Forward climate coverage
$1,410Home insurance / yr
0.3% / yrInsurance growth
0.58%Nonrenewal rate
county median (2+ published ZIPs)Insurance basis
97,912People within 30 min
3,536,604People within 2 hr
71,182Radius comparison (15 mi)
92.7People / sq mi
0.5%Federal land
69.8%Land at 15% slope or less
3.7%Soils rated "not limited" for septic (strict USDA rating)
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Cities and towns in Mercer County
Inside a city or town, that city usually issues building permits and sets zoning; the county’s rules above cover unincorporated land. Septic, wells and floodplain rules usually stay with the county or state everywhere.
Burgin · Harrodsburg
Answers from the rulebook for Mercer County
What the ordinances and state agencies actually say — one answer per question, each quoted from the official source and independently re-checked.
Mercer County rules
Building permitRequired
Structures placed or erected on property within Mercer County and Harrodsburg.
The page says virtually all structures are covered, including homes, manufactured homes, additions, decks, garages, pools, renovations, occupancy changes, and accessory structures larger than 200 square feet.
Agricultural structures in agriculturally zoned districts on more than 10 acres are described as exempt, but the principal dwelling is not exempt.
A zoning permit is required regardless of local or state permitting jurisdiction.
“The zoning ordinances & building code require a building permit for virtually all structures that are placed or erected on a piece of property within Mercer County & Harrodsburg.”
InspectionsRequired
Residential construction inspections administered by the Mercer County building inspector.
The listed required inspections are footer, foundation, framing, insulation, and final building inspection.
The county page also describes zoning preliminary and final inspections.
“Required Building Inspections 1. Footer Inspection 2. Foundation Inspection 3. Framing Inspection 4. Insulation Inspection 5. Final Building Inspection”
Certificate of occupancyRequired
Projects requiring the county building inspection process and final occupancy approval.
Final plumbing, electrical, and/or septic inspections must be performed before the final inspection for the Certificate of Occupancy may be scheduled.
After completing all required inspections, the building inspector sends out the Certificate of Occupancy.
“Once the final plumbing, electrical, and or septic inspections have been performed, the final inspection for the Certificate of Occupancy may be scheduled. After completing all the required inspections, the building inspector will send out the Certificate of Occupancy.”
County-wide zoningPresent (with conditions)
Zoning ordinances applying to property in Mercer County and Harrodsburg.
The cited county page describes zoning ordinances and building-code permitting but does not provide the operative district schedule.
“The zoning ordinances & building code require a building permit for virtually all structures that are placed or erected on a piece of property within Mercer County & Harrodsburg.”
Local zoningVaries (with conditions)
Aggregate of local zoning within Mercer County, including Mercer County zoning, Harrodsburg zoning, and the Burgin exception; this claim does not state that the county administers every municipal ordinance.
Harrodsburg and Mercer County zoning ordinances are listed on the county ordinances page.
Burgin does not participate in the joint planning operations and has no zoning ordinances or maps for properties within city limits.
“Note: The City of Burgin, KY does not participate in the joint planning operations of the Commission and as a result, there are no zoning ordinances or maps for properties that reside physically within the city limits.”
Zoning districtsPublished (with conditions)
Mercer County zoning districts and maps, subject to official zoning determinations by planning commission staff.
The county publishes 29 Mercer County maps plus a master county map.
The maps are general references and should not be relied upon to verify zoning.
Official zoning determinations should be made by contacting planning commission staff.
Burgin has no county joint-planning zoning ordinances or maps within city limits.
“There are 29 maps plus a master county map for Mercer County. To determine which map is the right one to view, click on the map titled “Cover”. It is a master map that will show the various map grids.”
SetbacksSpecified
Construction and structure placement in Mercer County, including projects processed through the Planning Commission and zoning enforcement office.
The Planning Commission verifies setbacks, use, and placement during the permitting process.
A preliminary zoning inspection ensures compliance with setbacks and a final inspection verifies use and size.
The zoning inspections are performed by the zoning enforcement office of the Planning Commission and require no appointments.
If placement may encroach on setbacks, the applicant may request an on-site inspection by the enforcement officer.
If construction is within a flood plain, special permits must be obtained from the state Division of Water before the building permit is issued.
“The permitting process begins in the office of the Planning Commission. Setbacks, use and placement is verified by commission staff. [...] The zoning inspections consist of a preliminary inspection to ensure compliance with setbacks and a final inspection to verify use and size. These two inspections are performed by the zoning enforcement office of the planning commission and require no appointments.”
One more reviewed finding on this topic
Specified — Construction and placement of structures in Mercer County and Harrodsburg where zoning staff verify setback compliance.
“Congratulations on your decision to build a new structure in Mercer County or Harrodsburg. [...] The permitting process begins in the office of the Planning Commission. Setbacks, use and placement is verified by commission staff.”
Who permits septicCounty (with conditions)
Septic evaluation for projects outside Harrodsburg city limits.
The county page identifies the Mercer County Health Department as the provider of the septic evaluation.
State septic regulations also govern permits and standards.
“If the project is outside the city limits of Harrodsburg, you will also need: Copy of the Septic Evaluation provided by the Mercer County Health Department.”
Mandatory utility hookupConditional
Residential building projects in Mercer County and Harrodsburg.
Projects within Harrodsburg require copies of paid sewer and water tap fees before final inspection.
Projects outside Harrodsburg city limits require a septic evaluation from the Mercer County Health Department.
“If the project is within the City of Harrodsburg, you will also need: Copy of paid sewer & water tap fees.(provided prior to Final Inspection)”
One more reviewed finding on this topic
Conditional — Projects outside Harrodsburg city limits in Mercer County.
“If the project is outside the city limits of Harrodsburg, you will also need: Copy of the Septic Evaluation provided by the Mercer County Health Department.”
Agricultural exemptionConditional
Structures used for agricultural purposes in agriculturally zoned districts on more than 10 acres.
The exemption does not include the principal dwelling on a 10-acre-or-larger tract.
The source describes this as a permit exemption, not an exemption from zoning or other requirements.
“Additionally structures used for agricultural purposes in agriculturally zoned districts on more than 10 acres of land. (This exemption does not include the principal dwelling on a 10 acre or larger tract of land)”
Subdividing landRegulated (with conditions)
Subdivision or resubdivision of land within Mercer County, excluding Burgin, under the Harrodsburg-Mercer County Subdivision Regulations.
Burgin opted out of the Joint Planning Agreement.
All subdivision of land as defined by KRS 100.111(22) must receive planning commission approval.
A plat must be approved before land may be subdivided or the plat recorded.
Outside Harrodsburg and Burgin municipal limits, Mercer Fiscal Court approves proposed improvements.
amendment date: 2024-03-12
“All subdivision of land as defined in KRS 100.11 1 (22) as amended from time to time shall receive planning commission approval.”
Building in a floodplainRequired
Construction determined to be within a floodplain in Mercer County.
Special permits must be obtained from the state Division of Water before the building permit will be issued.
“If the construction is determined to be within a flood plain, special permits must be obtained from the state Division of Water before the building permit will be issued.”
Permit feesPublished (with conditions)
Residential building permits and renovation or occupancy-change permits using the Mercer County application.
The application states a minimum fee of $75.00.
The stated square-foot rate applies to new construction and to affected areas for renovations or occupancy changes.
new construction fee: 0.2 USD per square foot under roof (Minimum $75.00) · renovation or occupancy-change fee: 0.2 USD per square foot of affected area (Minimum $75.00)
“Fee is $0.20 per square ft under roof (new) $0.20 per sq ft Renovations-Occupancy Changes (areas affected). Min $75.00”
Permit processPublished (with conditions)
Mercer County building and zoning permit process.
The process begins with the Planning Commission; setbacks, use, and placement are verified; the building inspector performs construction-plan and floodplain review; the permit must be posted after issuance.
Required application materials include deed or ownership proof, construction plans, truss plans, PVA building information, and an approved subdivision plat or site plan if available.
“The permitting process begins in the office of the Planning Commission. Setbacks, use and placement is verified by commission staff. The permit is immediately forwarded to the building inspector who performs construction plan and flood plain review with the applicant or property owner.”
Kentucky rules that apply here
Owner-builder exemptionConditional
A homeowner in Mercer County seeking a Kentucky plumbing permit to construct, install, or alter plumbing, sewerage, or drainage in a home occupied by the homeowner or constructed by the homeowner for the homeowner's own personal residential use.
The permit application must be made before work begins.
The homeowner must file an affidavit agreeing to abide by the regulation.
All work must comply with 815 KAR Chapter 20.
All work must be personally performed by the homeowner.
The homeowner must not have obtained another homeowner permit for construction of a new home within the previous five years.
A plumbing permit is still required for covered plumbing work.
The current residential one- and two-family plumbing permit fee is $50 plus $14 per opening, effective March 1, 2022.
residential plumbing permit base fee: 50 USD (One- and two-family residential permits.) · residential plumbing permit opening fee: per 14 USD (Per plumbing fixture, appliance, or opening, domestic water heater, and certain separately metered water or sewer services.) · homeowner permit frequency limit: 5 years (The homeowner shall not have obtained another homeowner permit for construction of a new home within the preceding five years.) · fee schedule effective date: 2022-03-01
“A homeowner who wishes to construct, install, or alter plumbing [...] for the homeowner's own personal residential use [...] work shall be personally performed by the homeowner”
One more reviewed finding on this topic
Conditional — An individual property owner performing heating, ventilation, and air conditioning work on property the individual owns and occupies.
“KRS 198B.650 to 198B.689 shall not apply to: [...] (3) An individual owner of real property while practicing heating, ventilation, and air conditioning work on or within property owned and occupied by the individual;”
Building code adoptedAdopted (with conditions)
Buildings constructed statewide in Kentucky, including residential and nonresidential construction subject to the Kentucky Building Code and Kentucky Residential Code.
The 2015 International Building Code is the mandatory state building code for buildings constructed in Kentucky, subject to Kentucky amendments in the 2018 Kentucky Building Code.
One-family dwellings, two-family dwellings, and townhouses are governed by 815 KAR 7:125 and the 2015 International Residential Code with Kentucky amendments in the 2018 Kentucky Residential Code.
Permits, inspections, and certificates of occupancy are not required for a single-family dwelling unless required by local ordinance.
Residential occupancies that are not single-family dwellings, two-family dwellings, or townhouses must comply with the 2015 International Building Code and the 2018 Kentucky Building Code.
Manufactured homes are governed by KRS 227.550 through 227.665.
base building code: 2015 International Building Code (Kentucky amendments in the 2018 Kentucky Building Code supersede conflicting provisions) · residential code: 2015 International Residential Code; 2018 Kentucky Residential Code amendments (Applies to single-family dwellings, two-family dwellings, and townhouses under 815 KAR 7:125) · mandatory effective date: 2019-01-01
“Building Code. The 2015 International Building shall be the mandatory state building code for all buildings constructed in Kentucky except that: (1) The Kentucky amendments in the 2018 Kentucky Building Code shall supersede any conflicting provision in the 2015 International Building Code; (2) One (1) family dwellings, two (2) family dwellings, and townhouses shall be governed by 815 KAR 7:125; and (3) Manufactured homes shall be governed by KRS 227.550 through 227.665.”
4 more reviewed findings on this topic
Adopted — Single-family dwellings, two-family dwellings, and townhouses constructed in Kentucky, including Mercer County.
“Except as provided in subsection (2) of this section, the 2015 International Residential Code for One (1) and Two (2) Family Dwellings (IRC) shall be the mandatory state residential building code for all single-family dwellings, two (2) family dwellings, and townhouses constructed in Kentucky, except that the Kentucky amendments in the 2018 Kentucky Residential Code shall supersede any conflicting provision in the 2015 IRC.”
Adopted (with conditions) — Kentucky buildings subject to the Kentucky Building Code; one- and two-family dwellings, townhouses, and manufactured homes are governed by separate provisions identified in the regulation.
“The 2015 International Building shall be the mandatory state building code for all buildings constructed in Kentucky except that:”
Adopted (with conditions) — Kentucky building and residential codes applicable statewide, including Mercer County.
“The Department of Housing, Buildings and Construction adopted the 2018 Kentucky Building Code, Second Edition and the 2018 Kentucky Residential Code, Second Edition on August 3, 2019.”
Adopted — Mandatory Kentucky residential building-code standards for single-family dwellings, two-family dwellings, and townhouses constructed statewide, including unincorporated areas.
“Except as provided in subsection (2) of this section, the 2015 International Residential Code for One (1) and Two (2) Family Dwellings (IRC) shall be the mandatory state residential building code for all single-family dwellings, two (2) family dwellings, and townhouses constructed in Kentucky, except that the Kentucky amendments in the 2018 Kentucky Residential Code shall supersede any conflicting provision in the 2015 IRC.”
Camping on your landLimited
Camping or sleeping in the specified public and private pedestrian or vehicle-use areas statewide.
The person must knowingly enter or remain in a listed area with intent to sleep or camp.
The area must not have been designated for sleeping or camping, or the individual must lack authorization to sleep or camp there.
The listed areas include streets, sidewalks, areas under bridges or underpasses, paths, parks, cemeteries, and other areas designated for pedestrians or vehicles, including ingress or egress areas to businesses, homes, or public buildings.
The first offense is a violation; a second or subsequent offense, or a first offense where the person refuses to cease, is a Class B misdemeanor.
The section does not prohibit customary and temporary use of recreational camping areas, rest areas, or other properties specifically designated for resting or sleeping.
Temporary sleeping in a vehicle parked lawfully on a public road, street, or parking lot is not prevented when sleeping and parking occur for less than twelve (12) hours.
temporary vehicle sleeping period: < 12 hours (The vehicle must be parked lawfully on a public road, street, or parking lot.)
“A person is guilty of unlawful camping when he or she knowingly enters or remains on a public or private street, sidewalk, area under a bridge or underpass, path, park, cemetery, or other area designated for use by pedestrians or vehicles, including areas used for ingress or egress to businesses, homes, or public buildings, with the intent to sleep or camp in that area, when the area has not been designated for the purpose of sleeping or camping or the individual lacks authorization to sleep or camp in the area.”
2 more reviewed findings on this topic
Allowed (with conditions) — Temporary camping locations for unsheltered homeless individuals designated by local governments under Kentucky law.
“A local government may designate indoor or outdoor areas with defined boundaries in an area zoned for commercial or industrial use, separate from any area frequently used for public purposes, as a temporary camping location for unsheltered homeless individuals.”
Limited — Temporary parking of recreational vehicles on public or private property associated with specified publicly announced events.
“Nothing in KRS 219.310 to 219.410 shall be construed to apply to the temporary parking of recreational vehicles on public or private property, for not more than thirty (30) days, associated with festivals, fairs, sporting events, yard sales, or other publicly announced events.”
Accessory dwellingsLimited
Accessory dwelling units on lots containing a single-family home in a county containing a consolidated local government, when a new lease is initiated after June 27, 2025 and the lot is in a traditional single-family home zone.
The owner may not lease or allow the accessory dwelling unit to be occupied unless the owner primarily resides in the single-family home, multifamily housing unit, or accessory dwelling unit on the lot.
The restriction applies only in a county containing a consolidated local government.
A traditional single-family home zone is a zone that, as of January 1, 2025, did not include multifamily homes as a permitted use.
The restriction does not apply to a lot containing only one single-family home and no accessory dwelling unit.
The statutory effective date is June 27, 2025.
new lease applicability date: > 2025-06-27 (The statute applies to new leases initiated after June 27, 2025.)
“In a county containing a consolidated local government, for new leases initiated after June 27, 2025, a property owner shall not lease or allow to be occupied any single-family home, multifamily housing unit, or accessory dwelling unit located on a lot that contains a single-family home and that is located in a traditional single-family home zone, unless the owner primarily resides in the single-family home or multifamily housing unit or an accessory dwelling unit on the lot.”
Septic permitRequired
On-site sewage disposal systems subject to Kentucky Cabinet administrative regulation, including systems in Mercer County.
Permit must be obtained from the local health department before construction, installation, or alteration.
The permit application includes DFS-307, a $50 on-site sewage disposal permit fee, and the fee established by the local board of health.
Cluster-system plan review is submitted to the Environmental Management Branch and carries a $600 fee payable to the Kentucky State Treasurer.
Permits are generally issued only to certified installers, subject to homeowner-permit exceptions.
state on-site sewage disposal permit fee: 50 USD (Additional local board of health fee may apply) · cluster-system plan review fee: 600 USD (Payable by check or money order to the Kentucky State Treasurer)
“KRS 211.350 provides that no person, firm, or corporation shall construct, install, alter or cause to be constructed, installed, or altered any on-site sewage disposal system subject to administrative regulation by the cabinet without having first obtained an on-site sewage disposal permit from the local health department.”
One more reviewed finding on this topic
Required — Construction, installation, or alteration of an onsite sewage disposal system subject to Kentucky Cabinet regulation.
“a permit to construct, install, or alter an on-site sewage disposal system shall be obtained prior to construction of any portion of that system.”
Septic inspectionRequired
Every on-site sewage disposal system in Mercer County that is installed, constructed, altered, or repaired.
The inspection must be performed by a certified inspector.
The Kentucky Onsite Sewage Disposal Systems Program is administered through local health departments, and local health department septic inspectors perform site evaluations and inspections.
A site evaluation is required before obtaining a permit to construct, install, or alter an on-site sewage disposal system; the permit must be obtained before construction of any portion of the system.
A certified Kentucky onsite septic installer must install the system based on the site-evaluation results, unless a homeowner obtains a homeowner’s permit through the local health department to install the system.
A variance may not waive a site evaluation or system inspection.
inspection applicability: installed, constructed, altered, or repaired systems · permit timing: before construction of any portion of the system
“Every on-site sewage disposal system installed, constructed, altered, or repaired shall be inspected by a certified inspector.”
2 more reviewed findings on this topic
Required — On-site sewage disposal systems in Kentucky, including Mercer County.
“A variance shall not be granted: To waive of site evaluation or system inspection;”
Required — Every Kentucky onsite sewage disposal system that is installed, constructed, altered, or repaired.
“Every on-site sewage disposal system installed, constructed, altered, or repaired shall be inspected by a certified inspector.”
Off-grid sanitationProhibited
Use of seepage pits, cesspools, or dry wells as onsite sewage disposal systems statewide in Kentucky, subject to the Section 13 exception.
The prohibition is subject to the exception provided in Section 13 of 902 KAR 10:085.
Section 13 permits limited repair or alteration of existing seepage-pit systems when municipal or public sewage treatment is unavailable and repair or alteration is required because of malfunction, damage, or upgrade.
A limited single-family vacant-lot exception applies to certain lots purchased on or before May 1, 1992, if bona fide construction began by December 25, 1992.
“Except as provided in Section 13 of this administrative regulation, use of seepage pits, cesspools, or dry wells;”
One more reviewed finding on this topic
Allowed (with conditions) — Use of an approved private onsite sewage disposal system for a building where a public sewer is unavailable.
“If a sewer is not available, the house drain from a building shall connect with an approved private sewage disposal system.”
Well permitNot required
Construction or abandonment of a private water well by a property owner statewide in Kentucky.
Construction, modification, and abandonment must be performed by a Kentucky Certified Water Well Driller.
The certified driller must complete and submit required documentation within sixty days after completion.
The conclusion concerns owner permitting applications and fees; it does not eliminate the separate driller-certification requirement.
well documentation submission deadline: 60 days after completion
“there are no permitting applications or fees for constructing or abandoning a water well required of the property owner.”
2 more reviewed findings on this topic
Not required — Construction or abandonment of a private water well by the property owner in Kentucky, including Mercer County.
“In Kentucky, there are no permitting applications or fees for constructing or abandoning a water well required of the property owner.”
Limited — Construction, alteration, repair, or abandonment of water supply wells in Kentucky.
“A person shall not construct, alter, repair, or abandon a water well without first obtaining a water well driller or water well driller assistant certificate”
Driveway accessRequired
New or additional private farm or single-family-dwelling driveway approaches requiring work in Kentucky Department of Highways rights-of-way, including Mercer County.
The owner or occupant must make formal written application to the District Engineer.
Approval by the District Engineer is required before the specified follow-on requirements apply.
The applicant must furnish required drainage pipe, tile, or other drainage structures at the applicant's expense.
The Department may participate up to $300 for the described drainage, grading, and surfacing work within right-of-way limits.
No indemnity bond or other security is required for a farm or single-family-dwelling driveway approach unless estimated construction cost within right-of-way limits exceeds $300.
department participation limit: <= 300 USD (For described drainage, grading, and surfacing work within right-of-way limits) · security threshold: > 300 USD (Estimated construction cost within right-of-way limits)
“The owner or occupant of property, who desires to construct new or additional private farm or single family dwelling driveway approaches, shall make formal application in writing”
2 more reviewed findings on this topic
Required — New or additional private farm or single-family dwelling driveway approaches on Kentucky Department of Highways rights-of-way.
“The owner or occupant of property, who desires to construct new or additional private farm or single family dwelling driveway approaches, shall make formal application in writing, to the District Engineer of the Department of Highways.”
Required — New, additional, relocated, or modified driveway entrance approaches serving commercial property or property used for a purpose other than farming or a single-family dwelling.
“The owner or occupant of property, used for commercial or any purpose other than farming or single family dwelling, who desires to construct new or additional driveway entrance approaches, to relocate, or make other changes in existing driveway entrance approaches thereto, shall make application for a permit to the District Engineer of the Department of Highways upon standard forms furnished by the Transportation Cabinet.”
Campground & park staysTemporary only (with conditions)
Sleeping temporarily in a recreational vehicle or other vehicle in a vehicle-based location covered by KRS 511.110.
The vehicle must be parked lawfully on a public road, street, or parking lot.
Sleeping and parking at the location must occur for less than twelve (12) hours.
This provision does not establish permission for long-term or permanent RV occupancy on private land.
KRS 511.110 separately prohibits camping in specified areas when the area has not been designated for sleeping or camping or the person lacks authorization.
maximum sleeping and parking period: < 12 hours
“Nothing in this section shall prevent a person from sleeping temporarily in his or her vehicle parked lawfully on a public road, street, or parking lot, where the sleeping and parking of the vehicle at the location occur for a period of less than twelve (12) hours.”
county zoning authorityGeneral
Kentucky counties' statutory authority to enact zoning regulations, including county-regulated areas outside incorporated municipalities as determined by the applicable planning-unit and political-boundary structure.
The statute expressly authorizes both cities and counties to enact zoning regulations.
A zoning regulation must contain text listing the types of zones and regulations applicable in each zone, uniform throughout the zone, and provisions for variances, conditional-use permits, and nonconforming uses.
Authorized subjects include land activities, structure dimensions and locations, open-space and distance requirements, density, special-interest districts, fringe areas, and activities or structures near thoroughfares, water bodies, public facilities, aircraft facilities, unique places, and floodplains.
Agricultural land must have no regulations except that setback lines may be required for streets and highways; floodway or floodplain buildings or structures may be fully regulated; mobile homes and other dwellings may be regulated; and uses under KRS 100.111(2)(c) may be regulated as conditional uses.
The applicable planning unit and political boundaries determine the area governed by a county zoning regulation.
“Cities and counties may enact zoning regulations which shall contain:”
One more reviewed finding on this topic
General — Kentucky counties may adopt permanent land-use regulations, including zoning, through the applicable planning-unit process; this authority reaches county jurisdiction, including unincorporated areas, subject to the statutory planning prerequisites.
“When all required elements of the comprehensive plan have been adopted in accordance with the provisions of this chapter, then the legislative bodies and fiscal courts within the planning unit may enact permanent land use regulations, including zoning and other kinds of growth management regulations”
county building authorityGeneral
Kentucky fiscal courts may adopt and enforce construction regulations and may require building permits for construction in the county, including residential construction in unincorporated areas.
The construction regulations must be adopted by county order or resolution.
The regulations operate pursuant to KRS 198B.060 and the Uniform State Building Code framework.
A county building inspector may administer the regulations.
No person may build, erect, construct, reconstruct, remodel, relocate, alter, or repair a building within the county without first obtaining a building permit from the building inspector when the county permit system applies.
Permit fees must be reasonable and may not exceed the cost of the service provided.
A person aggrieved by the building inspector's ruling, order, or decision may appeal under KRS 198B.070.
permit fee ceiling: <= cost of the service provided
“The fiscal court of any county shall have authority, by order or resolution, to adopt, and to enforce, regulations governing construction as defined by KRS 198B.010 pursuant to the provisions of KRS 198B.060.”
One more reviewed finding on this topic
General — Kentucky county authority, as a local government, to enforce the Uniform State Building Code and issue building permits within its jurisdiction, including unincorporated residential construction.
“Each local government shall employ a building official or inspector and other code enforcement personnel as necessary, or shall contract for inspection and code enforcement services in accordance with subsections (8) and (11) of this section to enforce the Uniform State Building Code within the boundaries of its jurisdiction, except that permits, inspections, and certificates of occupancy shall not be mandatory for single-family residences unless a local government passes an ordinance requiring inspections of single-family residences.”
Inside cities and towns in Mercer County
Municipal rules found while researching the county. They apply inside that city or town, not to unincorporated land.
Living in an RVTemporary only (with conditions)
Travel trailers and recreational vehicles within the City of Harrodsburg limits.
Travel trailers or recreational vehicles are not to be used for permanent habitation within the city limits.
Temporary habitation may be allowed only as a conditional use.
A Conditional Use Permit issued by the Board of Adjustments & Appeals is required.
The conditional use provision applies in any zoning district.
“NOTE: A travel trailer or recreational vehicle is not considered as a mobile-home. As such, they are not designed for nor shall they be used for permanent habitation within the city limits. Travel Trailers may be allowed as a Conditional Use if the intent is for temporary habitation and shall require a Conditional Use Permit issued by the Board of Adjustments & Appeals in ANY zoning district.”
Mandatory utility hookupWater and sewer (with conditions)
Building projects within the City of Harrodsburg.
Paid sewer and water tap fees are required before final inspection.
Projects outside Harrodsburg city limits instead require a septic evaluation from the Mercer County Health Department.
“If the project is within the City of Harrodsburg, you will also need: Copy of paid sewer & water tap fees.(provided prior to Final Inspection)”
Still unanswered
We looked and could not find an official answer yet. Silence is not permission — ask the county directly.
Minimum dwelling size — Minimum dwelling floor area in Mercer County zoning districts.
Minimum lot size — Minimum lot size in Mercer County zoning districts.
Lot coverage — Lot-coverage limits in Mercer County zoning districts.
Building height — Building-height limits in Mercer County zoning districts.
Tiny homes — Tiny-home occupancy in Mercer County, including unincorporated areas and the City of Harrodsburg.
2 more unanswered
Manufactured homes
Short-term rentals
Each answer was extracted from an official source and independently re-checked against that source by a second reviewer. That is an evidence check, not legal advice. Rules change; confirm with the authority before you buy or build.
Living off-grid in Mercer County, Kentucky
Is Mercer County a good place to live off-grid or homestead?
Mercer County scores 50/100 on the Bolthole Index, a solid county profile. Its strengths: manageable long-term carry cost and mixed durability signals. Watch-outs: about 97,912 people within a 30-minute drive and a weaker property-autonomy legal backdrop.
Do you need a building permit in Mercer County, Kentucky?
Mercer County generally requires a residential building permit, and it enforces county zoning. Onsite septic is permitted by Mercer County Health Department. Owner-builders may act as their own contractor to build their home. These answers are quoted from official sources and independently re-checked. Rules change and cities within the county differ — always confirm with the county before you buy or build.
How much does land cost in Mercer County, Kentucky?
Land in Mercer County runs about $5,326 per acre, based on the latest county data.
What is the water situation in Mercer County?
Mercer County gets about 49.8" of rain a year, with severe drought in roughly 2.2% of years.
How remote is Mercer County?
A representative private-land location has about 97,912 people within a 30-minute drive and 3,536,604 within two hours. The road-network catchments count population across county lines and clusters of smaller cities; straight-line radius values remain available as a comparison.
