Building permits, zoning and septic rules in the Village of Ada, Ohio

At a glance

Zoning

Village of Ada zoning ordinance, enforced by the village zoning inspector²

Zoning certificate

Required for new construction, including accessory buildings and mobile homes¹

Application

Online, at the Ada Police Department, or at the village business office⁵

Septic

Kenton-Hardin Health Department site evaluation and installation permit⁶⁴

Property tax

Hardin County effective rate of 1.1%⁷

Who to call

Contact details are copied from each office’s official page and were checked against it on October 14, 2026.

Does Ada, Ohio have zoning, and what does it mean for your lot?

The Village of Ada has its own zoning ordinance, and the village zoning inspector enforces it inside village limits². The ordinance sets residential, commercial, industrial, manufactured-home and planned-unit districts, and the village posts a zoning map on its website³. Dimensional rules differ by district, so look up your parcel's district before you plan a building; the district text for residential lots was not captured for this guide, so confirm setbacks and lot size with the zoning inspector. Land subdivision inside the village is regulated by its own subdivision regulations⁸. Outside village limits, Hardin County's townships zone separately and coverage varies by township⁹.

Do you need a building permit in Ada, and who issues it?

New construction in the Village of Ada, including accessory buildings and mobile homes, needs a zoning certificate before work begins¹. Exterior structural changes, a change of use, demolition of 1,000 square feet or more, and moving a structure of 200 square feet or more also need one¹. The zoning inspector issues the certificate within 30 days of an application, and fees must be paid before the application is reviewed¹. A plot plan in duplicate goes with the application⁵. Whether the village or the county also issues a separate building-code permit for houses could not be confirmed; ask the village office before you pour a foundation.

How do you apply for a zoning certificate in Ada?

Applications go online through the village website, to the Ada Police Department at any hour, or to the village business office on weekdays from 8:00am to 5:00pm⁵¹⁰. The village inspects new construction three times: before the certificate is issued, after the foundation is excavated and before the pour, and when the structure is complete¹¹. A certificate is also required before any structure, building or land is used, and it stays provisional until the final inspection is approved¹². Call the Village of Ada main office at (419) 634-4045¹⁰.

How do septic permits work for a home in Ada?

Septic permits in Hardin County come from the Kenton-Hardin Health Department under Ohio Administrative Code 3701-29⁴. The process starts with a Site Inspection Application and a $320 site-evaluation fee, followed by an installation permit costing $424 once the installer's scaled drawing is approved⁶. The permit is valid for one year, and installation is suspended from December 1 through March 1 by order of the Board of Health⁶. A follow-up inspection happens within 12 months of installation¹³. Whether your Ada lot can or must connect to a municipal sewer was not confirmed; ask the village office, because Ohio requires sewer connection where a public sewer is accessible and available¹⁴. Contact the health department at 419-673-6230¹⁵.

Can you live in an RV or tiny home in Ada?

Whether the village allows living in an RV or tiny home on a lot could not be confirmed, so ask the Ada zoning inspector at (419) 634-4045 before you move one onto a parcel¹⁰. What is confirmed: a mobile home counts as new construction and needs a zoning certificate¹, and a manufactured home generally may not be occupied until the state inspector issues the inspection seal¹⁶. Ohio's campground rules cover licensed campgrounds, not an RV on your own lot¹⁷.

What stays with Hardin County and the state?

The village decides zoning and zoning certificates inside its limits, but several things stay with the county or state. Septic permits and private water system permits go through the Kenton-Hardin Health Department⁴; the private water system permit fee is $392.90 when one is needed¹⁸. Driveway work along county roads needs a permit from the county engineer¹⁹. Deeds, parcel splits, surveys and subdivision plats are approved at the Hardin County Engineer's Tax Map Department²⁰. For land outside the village, see the Hardin County page. Hardin County's effective property tax rate is 1.1% and the median property tax bill is $1,513⁷²¹.

Watch-outs

• Ada's building-code rules (the village code's Part Thirteen) and any owner-builder exemption inside the village could not be confirmed; ask the village office before assuming a house needs only a zoning certificate²².
• The state's owner-builder exception applies only where no certified building department has jurisdiction, and it does not decide zoning or septic²².
• Septic installation is suspended from December 1 through March 1, so a late-fall start can push your septic permit into spring⁶.

Sources

1. Village of Ada - Planning Commission & Zoning Ordinance (Village of Ada), quoted and re-checked
2. Village of Ada - Planning Commission & Zoning Ordinance (Village of Ada), quoted and re-checked
3. Ada Codified Ordinances, Chapter 1141 R-1 Residential District (Village of Ada), quoted and re-checked
4. Process for Obtaining Sewage Treatment System Permit, quoted and re-checked
5. Village of Ada - Planning Commission & Zoning Ordinance (Village of Ada), quoted and re-checked
6. Process for Obtaining Sewage Treatment System Permit, quoted and re-checked
7. Effective property tax rate: Bolthole Index county data
8. Ada Codified Ordinances, Chapter 1141 R-1 Residential District (Village of Ada), quoted and re-checked
9. Township Law, quoted and re-checked
10. Village of Ada Zoning Inspector and Village Business Office (adaoh.gov)
11. Village of Ada - Planning Commission & Zoning Ordinance (Village of Ada), quoted and re-checked
12. Village of Ada - Planning Commission & Zoning Ordinance (Village of Ada), quoted and re-checked
13. Process for Obtaining Sewage Treatment System Permit, quoted and re-checked
14. Rule 3745-42-07 | Best available technology for connection into sanitary sewers and centralized collection and treatment (Ohio statewide rule), quoted and re-checked
15. Kenton-Hardin County Health Department (hardinhealth.org)
16. Chapter 4781-7 | Manufactured home inspections (Ohio statewide rule), quoted and re-checked
17. Rule 3701-26-04 | Campground requirements (Ohio statewide rule), quoted and re-checked
18. Process for Obtaining Sewage Treatment System Permit, quoted and re-checked
19. Application for Permit Driveway Installation and/or Work Along Hardin County Roads, quoted and re-checked
20. Tax Map and Ditch Maintenance, quoted and re-checked
21. Median property tax bill: Bolthole Index county data
22. Ohio Administrative Code Rule 4101:8-1-01, Residential Code of Ohio Administration, quoted and re-checked

Written October 14, 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.