Dover

Kent County regulates ADUs on unincorporated parcels under a purpose-built ADU chapter in the Kent County Code: Chapter 101 — Accessory Dwelling Units, added by Ordinance 23-20 (introduced 2023-08-15 by Levy Court Commissioners Joanne Masten and Jeffrey W. Hall; adopted 2023-09-26). Companion amendments to Chapter 205 (Zoning) simultaneously revised the permitted-use tables so that an ADU — either attached (accessory apartment) or detached (cottage) — is a permitted use in all residential zoning districts, subject to Chapter 101 conditions. The ordinance is a local action, not a state preemption floor: Delaware has no statewide ADU law, and SB 87 remains pending as of 2026-04-20.

• Kent County Code Chapter 101 — Accessory Dwelling Units
• Kent County Code Chapter 205 — Zoning (Article V Permitted Uses, Article VI Conditions of Approval, Article VII Area and Bulk Requirements)
• Kent County Code Chapter 105 — Building Construction
• Ordinance 23-20 — original adopting ordinance

State-floor overlay: Delaware has NOT enacted a statewide ADU preemption law. SS1 for SB 23 (152nd General Assembly) died in committee when the session ended 2024-06-30; SB 87 (153rd General Assembly, chief sponsor Sen. Russ Huxtable) was reported favorably with Senate Amendment 1 on 2025-05-07 but was tabled at the full Senate floor and has not been taken up in the 2026 portion of the session as of 2026-04-20. In the absence of state preemption, Kent County's Chapter 101 is the authoritative ADU framework for unincorporated Kent. SEO-content sites (steadily.com, zookcabins.com) frequently mischaracterize Delaware as having a statewide ADU law — this is false as of 2026-04-20.

Kent County administers floodplain and environmental overlays that cut across its 16 incorporated municipalities and its unincorporated areas. The county's floodplain-management ordinance (Kent County Code Chapter 89) implements the FEMA National Flood Insurance Program; the effective Flood Insurance Study and FIRM panels for Kent County and incorporated areas are dated July 7, 2014 with subsequent LOMRs and pending updates along Tidbury Creek, Puncheon Run, Isaac Branch, and Iron Mine Prong. Kent contains 1,853 structures in the FEMA 100-year floodplain per the 2011 Delaware Floodplain Report (statewide figure 18,000+). Delaware does not have a CalFire-equivalent statewide WUI wildfire-hazard mapping regime, and Kent County does not operate a county-level WUI overlay.

• Kent County Floodplain Management Ordinance — Implements the FEMA National Flood Insurance Program for unincorporated Kent. ADUs proposed in a Special Flood Hazard Area (Zone A, AE) face elevation, venting, anchoring, and lowest-floor-elevation-certificate requirements that materially change construction cost. Coastal A and V zones are rare in Kent (predominantly a Delaware Bay watershed county) but present along the St. Jones River and Delaware Bay tidal reaches.
• FEMA Flood Insurance Rate Maps — Kent County and Incorporated Areas — FEMA is actively revising FIRMs along Tidbury Creek and tributaries, Puncheon Run, Isaac Branch, and Iron Mine Prong in Kent County. Owners considering ADUs on parcels near these waterways should pull the current effective panel plus any preliminary work-map-available (WMA) panels from the Delaware Flood Planning Tool at https://floodplanning.dnrec.delaware.gov/.
• DNREC Wellhead Protection and Source Water Protection Areas — DNREC administers source-water protection overlays that constrain on-site sewage design and land use within delineated wellhead protection areas. Kent County's Chapter 101 ADU ordinance expressly prohibits creation of an ADU served by an on-site wastewater system without a prior DNREC permit, which captures the overlay's operational effect without requiring a separate county overlay ordinance.
• Delaware Coastal Zone Act jurisdiction — Delaware's Coastal Zone Act primarily restricts heavy industrial and manufacturing uses within the coastal strip; it does not substantively regulate single-family residential or ADU development, but owners near the Bay or coastal wetlands should confirm wetlands-delineation compliance via DNREC before siting a detached ADU.
• Historic Districts (local) — Kent County does not operate a county-wide historic-preservation overlay for unincorporated parcels; historic-district review operates at the municipal level inside incorporated cities. Owners in or adjacent to a locally listed historic district should check with the relevant municipal historic-preservation commission before siting an ADU.

Permits for ADUs on parcels in unincorporated Kent County are issued by the Kent County Department of Planning Services (also known simply as the Kent County Planning Office), which is the official enforcement agency and whose Director of Planning Services is the appointed building official. Permitting is done through a combined Certificate of Use (ADU-specific under Chapter 101) and building permit (Chapter 105). The Levy Court explicitly excludes permitting work inside the limits of the 16 incorporated municipalities in Kent (Camden/Wyoming, Cheswold, Clayton, Dover, Dover AFB is a federal enclave, Felton, Frederica, Harrington, Hartly, Houston, Kenton, Magnolia, Milford, Smyrna, Viola, Woodside) — those jurisdictions operate their own ADU permit pathways.