ADU Pass
Washington
Daviess County portion
Also in: Martin County
ADU Pass helps homeowners in Washington, Daviess County, Indiana navigate the permit paperwork for building an accessory dwelling unit. This area covers 2 ZIP codes.
Map
ADU details
ADU legality: with-restrictions
Washington (Daviess County) has no dedicated ADU ordinance. ADU applicants apply for a building permit through the City Building Commission (within city + 2-mile area) and demonstrate the proposed unit fits the zoning district's accessory-use and density rules. Outside the 2-mile fringe, the Daviess County Plan Commission has jurisdiction.
Cost scenarios
| Scenario | Sq ft | Permit | Build | Total |
|---|---|---|---|---|
| minimum | 200 | $800 | $36,000 | $36,800 |
| 600 | 600 | $800 | $108,000 | $108,800 |
| midpoint | 550 | $800 | $99,000 | $99,800 |
| maximum | 900 | $800 | $162,000 | $162,800 |
Fee breakdown (as of 2026-04)
Permitting process
- Confirm jurisdiction (city, 2-mile fringe, or county) (~1d)
Call Washington Building Commissioner at (812) 254-8208 to confirm whether the parcel is inside city limits, within the 2-mile extraterritorial planning area (city jurisdiction), or in unincorporated Daviess County (Daviess County Plan Commission jurisdiction). - Verify zoning district and accessory-use compatibility (~7d)
Building Commission confirms the underlying residential district (e.g., R-1, R-2) permits a second dwelling unit as an accessory use, and identifies any minimum-lot-size, setback, or density limits that constrain ADU placement. - Septic / sewer feasibility (~21d)
If on septic, Daviess County Health Department issues a septic permit confirming the existing system can absorb a second dwelling unit, or that a new system can be installed. Sewer parcels confirm tap capacity with city utility. - Submit building permit application at Building Commission (~1d)
Paper application filed in person at 2113 Memorial Ave, Washington, IN 47501. Application includes site plan, floor plan, elevations, and contractor information (Indiana does not require a state GC license but contractors must provide insurance and any city-required registration). - Plan review by Building Commissioner (~14d)
Building Commissioner reviews against IRC 2018 (Indiana amendments) plus any city-specific egress, ventilation, and energy-code requirements (IECC 2018 base). - Permit issuance and fee payment (~3d)
Permit issued upon approval and payment. Fees collected at the Building Commission office. - Construction inspections
Footing, foundation, framing, plumbing rough, electrical rough, mechanical rough, insulation, and final. Inspections requested by phone to (812) 254-8208. - Certificate of occupancy (~5d)
After final inspection clears, Building Commission issues CO. Unit may then be occupied.
Viability (permitted uses)
- Long-term rental: yes 30+day rental of ADU permitted. No city rental-registration ordinance in effect.
- Short-term rental: with-restrictions Washington has no dedicated STR ordinance; Innkeeper's Tax (Daviess County) applies. Practical operation possible subject to building-permit conditions.
- Office rental: no Residential zoning does not allow standalone commercial office tenancy in an ADU.
- Home office: yes Home occupation permitted with restrictions on signage and customer traffic per zoning code.
- Studio / workshop: yes Personal artist or workshop use is a permitted accessory residential use.
- Agriculture: with-restrictions Indiana right-to-farm protections strong in Daviess County; backyard agriculture permitted on most residential lots.
- Relative support: yes Family-occupancy ADU explicitly compatible with single-family residential districts.
Contacts
Staff: Building Commissioner (Permits, inspections, zoning enforcement) bpowden@washingtonin.us
Utilities
- Water: Washington Water Department · 30d connect · $1,800
- Sewer: Washington Wastewater (city sewer for in-city parcels) / Daviess County Health Dept (septic for parcels outside service area) · 30d connect · $2,400
- Electric: Duke Energy Indiana · 21d connect · $1,500
- Gas: Vectren (CenterPoint Energy Indiana) · 30d connect · $1,200
Property values & taxes
Construction timeline
Realistic total: best 6mo · typical 9mo · worst 14mo
Financing
State ADU loans:
Insurance impact
HOA prevalence & preemption
Indiana has no HOA-ADU preemption. HOA prevalence in small-town Washington is low (8% estimate); most parcels are fee-simple lots without covenants restricting accessory dwellings.
Regulatory overlays (1)
- flood-zone — FEMA SFHA along East Fork White River corridor through northern Washington
Parcels within mapped Zone A/AE require finished-floor elevation above BFE and flood insurance for federally-backed financing. (map)
Technical envelope (climate & building code)
Climate & energy code
Building code
Amendments:
- Amendment
- Amendment
Legal history (timeline)
Current ordinance: Daviess County Zoning Ordinance (county-administered, applies outside Washington city + 2-mile fringe), adopted 2020-05-26, last amended 2023-01-04
- 2020-05-26 — Daviess County Zoning Ordinance Revision (county-ordinance)
Daviess County adopted a comprehensively-revised zoning ordinance covering unincorporated areas of the county.
Effect: Re-organized residential districts and accessory-use rules. The 2020 revision is the operative county zoning instrument; ADUs in unincorporated areas are evaluated under its accessory-use and minimum-lot provisions. - 2024-01-01 — Indiana Building Code update - 675 IAC adopting IRC 2018 base (state-law)
Indiana Department of Homeland Security maintains the state's adopted Indiana Residential Code (IRC 2018 with Indiana amendments) which governs ADU construction in Washington.
Effect: Indiana retains the IRC 2018 base for one- and two-family dwellings. Indiana amendments at 675 IAC 14 remove the IRC R313 residential fire-sprinkler mandate.
Known issues (1)
- policy-gap (since 2020-05-26) — Applicants depend on Building Commissioner's interpretation of accessory-use rules in the underlying residential district. Outcomes vary by parcel. (source)
Indiana state — ADU law and programs
State ADU law
Indiana enacted statewide ADU-permissive housing legislation in the 2026 session. House Enrolled Act 1001 (HEA 1001), authored by Rep. Doug Miller (R-Elkhart), was signed by Governor Mike Braun on 2026-04-14. The bill makes ADUs and commercial-to-residential conversions permitted uses by right unless a city, town, or county affirmatively opts out by 2026-12-31 via local ordinance. The bill also caps building permit fee increases (180-day delay before new permit-fee ordinances take effect), restricts certain residential design and aesthetic regulations, and requires every Indiana local government to hold a public housing-supply hearing in 2026 and report annually to the Indiana Housing and Community Development Authority. Earlier related bills (HB 1005 in 2025) addressed parts of the housing framework but did not preempt local ADU rules; HEA 1001 is the first true statewide ADU floor.
State financing programs
Indiana does not operate an ADU-specific statewide loan, grant, or forgivable-loan program. The Indiana Housing and Community Development Authority (IHCDA) administers general homeownership, down-payment-assistance, and affordable-housing-development programs that can apply to properties with ADUs when eligibility criteria are met, but none target ADU construction directly. HEA 1001 (2026) gave IHCDA a new oversight role — receiving annual housing-progress reports from every local government — but did not create new ADU financing.
State housing programs
Indiana's primary state-level ADU program is the new HEA 1001 (2026) framework: ADU-by-right permitting unless opted out, capped permit-fee escalation, restricted design regulation, and required local public hearings and annual progress reporting to IHCDA. There is no statewide pre-approved ADU plan catalog, no statewide ADU impact-fee waiver, and no statewide ADU rebate program. Earlier discussion in HB 1005 (2025) of broader housing-process reforms set the policy stage for HEA 1001.
- HEA 1001 ADU-by-right framework — ADUs are permitted uses statewide unless a city, town, or county opts out by ordinance before 2026-12-31. Localities that opt in (the default) must process ADU applications ministerially within their ordinary permit framework.
- HEA 1001 building-permit-fee cap — Local building-permit-fee increases must be published 180 days before they take effect. Limits on the size and frequency of increases apply after 2026-12-31.
- HEA 1001 local housing-supply hearing and reporting requirement — Every Indiana city, town, and county must hold a public hearing on housing supply in 2026 and submit annual progress reports to IHCDA on housing approvals, denials, and timelines.
Federal (United States) — ADU-relevant rules and programs
Federal ADU law
The United States has no federal statute that directly regulates accessory dwelling unit entitlement or design. Land-use authority over ADUs resides with states and local governments under the traditional police power. Federal engagement is limited to financing (Fannie/Freddie/FHA/VA/USDA), flood insurance (FEMA/NFIP), and discretionary housing programs (HUD), which are recorded in sibling sections of this file.
Federal financing programs
Federal housing-finance agencies and GSEs set nationwide underwriting rules that govern whether an ADU can be financed, appraised, and counted toward mortgage qualifying income. The relevant actors are Fannie Mae, Freddie Mac, FHA (HUD), VA, and USDA Rural Development.
Federal tax credits
There is no ADU-specific federal tax credit. ADUs may incidentally qualify for existing federal energy-efficiency and clean-energy tax credits when the ADU construction includes qualifying measures.
Federal housing programs
HUD administers several discretionary programs that can fund ADU-related activity at the grantee's election, but none is an ADU-specific program.
ZIP Codes
- 47501
- 47568
Post Office
- 405 Center St, 47501