How to Get a ADU Permit in City of Washington, IN (2026 Guide)
Everything you need to know about adu permits in City of Washington, IN, local requirements, fees, timelines, and how to apply.
By Joey, Founder · Last updated May 15, 2026 · How we research →
Check your specific adu project
Get an instant, personalized answer for your exact project details in City of Washington.
Free Permit Lookup →Do You Need a ADU Permit in City of Washington?
Based on City of Washington's local building codes, you'll need a permit when:
IN (covering ZIP 47501), permits are issued by the City of Washington Building Commission, enforcing the 2020 Indiana Residential Code (incorporating the 2018 IRC (IN base), 2017 NEC, Indiana Plumbing Code (Indiana Plumbing Commission), Indiana Fuel Gas Code, Indiana Mechanical Code, and 2009 IECC w/ IN amendments with state amendments). IECC Climate Zone 4A. An accessory dwelling unit requires a full building permit, trade permits, and zoning approval. Confirm ADU is permitted in your zoning district before designing. Washington is the county seat of Daviess County, southwestern Indiana. Home to Indiana's 4th-largest Amish community (~14.6% of county); Amish horse-barn permits common east of town. Crane NSWC federal installation north in Martin County draws defense workforce. Eastside Park summer food-truck gathering is a community fixture. White River and East Fork White River drainages create FEMA SFHA in low-lying parcels.
Permit Fees in City of Washington
Based on local City of Washington permit data, fees for adu projects typically range:
Here's how fees break down by project scope nationally:
| Project Scope | Typical Permit Fee |
|---|---|
| Garage or basement conversion ADU | $500 – $3,000 |
| Attached ADU (addition) | $800 – $5,000 |
| Detached ADU (new construction) | $1,000 – $8,000+ |
| Impact fees (where applicable) | $0 – $10,000+ (waived in many states) |
| Utility connection fees | $1,000 – $5,000+ (for new water/sewer connections) |
| Architectural plans | $2,000 – $10,000 (separate from permit) |
Fees are typically calculated based on estimated project value. Contact City of Washington Building Commission for exact amounts.
How Long Does It Take?
In City of Washington, typical approval time for adu permits is about 4 weeks.
More complex projects requiring structural review or variances may take longer. Simple projects may qualify for expedited or over-the-counter review in some cases.
How to Apply for a ADU Permit in City of Washington
- 1 Check requirements: Use our free lookup tool or contact City of Washington Building Commission to confirm your project needs a permit.
- 2 Gather documents: Prepare your application, site plan, construction drawings, and any other required documents.
- 3 Submit online: City of Washington accepts applications online at City of Washington Building Commission.
- 4 Pay fees: Pay the applicable permit fees ($400 – $1,500).
- 5 Wait for approval: Your application will be reviewed by City of Washington plan reviewers. Typical turnaround is about 4 weeks.
- 6 Begin work: Once approved, post your permit visibly at the job site before starting work.
- 7 Schedule inspections: Call City of Washington Building Commission at (812) 254-8208 to schedule required inspections at each phase of the project.
City of Washington Building Department Contact
Required Inspections in City of Washington
Most adu projects in City of Washington require inspections at each construction stage:
Foundation Inspection, Footing dimensions, depth below frost line, rebar placement, anchor bolt locations, soil bearing conditions, and compliance with structural engineering plans.
Framing Inspection, Wall framing, headers, connections to existing structure (for attached/conversions), fire separation between ADU and main house, egress windows/doors, ceiling height compliance, and overall structural integrity per approved plans.
Rough-In Trade Inspections, Electrical: circuits, GFCI/AFCI, panel capacity. Plumbing: DWV routing, supply lines, water heater, fixture connections. Mechanical: HVAC ductwork, ventilation, combustion air. All work must be visible.
Final Inspection, All fixtures operational, smoke and CO detectors, GFCI tested, kitchen appliances connected, egress windows functional, address numbers posted, and overall compliance with approved plans. Certificate of occupancy issued upon passing.
Schedule inspections with City of Washington Building Commission at (812) 254-8208 at least 24–48 hours in advance.
Frequently Asked Questions
Whether you need a permit depends on the size and scope of your adu project. In City of Washington, some smaller projects are exempt while larger ones require a permit. Use our free lookup tool to check your specific situation.
Permit fees for adu projects in City of Washington typically range from $400 – $1,500. Fees are usually based on the estimated project value.
Typical approval time in City of Washington is about 4 weeks. Complex projects requiring structural review may take longer.
In most cases, homeowners in City of Washington can pull permits and perform work on their own primary residence as an owner-builder. You're still responsible for meeting all code requirements and passing inspections.
Working without a required permit in City of Washington can result in fines, stop-work orders, required removal of completed work, and complications when selling your home.
Ready to check your adu project in City of Washington?
Use our free lookup tool to get a personalized answer based on your specific project details.
Free Permit Lookup →Other Permit Guides for City of Washington, IN
Explore more permit guides for City of Washington:
ADU Permits in Nearby Cities
See adu permit requirements in other Indiana cities:
See Detailed ADU Rules for City of Washington
View all local rules, exemptions, and fee details on the permit page.
ADU Permit Rules →