Austin ADU Permit Timeline: How Long Does It Actually Take? (2026)

The Realistic ADU Permit Timeline in Austin

One of the most common questions we hear is "how long will this take?" The answer depends on your project, but here's what to expect in 2026 based on current City of Austin Development Services Department (DSD) processing times.

Overview: 8 to 14 Months Total

From the day you decide to build an ADU to the day you get your certificate of occupancy, plan for 8 to 14 months. Here's the breakdown by phase.

Phase 1: Design & Pre-Application (4-8 weeks)

Before you submit anything to the city, you need plans. This phase includes:

• Hire an architect or designer: Get site-specific plans drawn up. Many Austin designers now specialize in ADUs and have template plans that speed this up.
• Survey your lot: You'll need a current survey showing trees, setbacks, impervious cover, and utility locations. Budget 2-3 weeks for this.
• Pre-application meeting (optional): DSD offers free pre-application consultations. Not required, but can flag issues early.

Phase 2: Permit Review (6-12 weeks)

This is where most of the waiting happens. After you submit your plans to DSD:

• Initial review: 4-6 weeks for the first round of comments
• Revisions: If comments come back (they usually do), your architect makes changes and resubmits. Each revision cycle takes 2-4 weeks.
• Typical total: Most ADU permits take 2-3 review cycles, so budget 8-12 weeks total.

The city has been working to speed up ADU permits since the HOME Initiative passed. Simple projects that match standard configurations can sometimes get through in as few as 4 weeks.

Phase 3: Construction (3-6 months)

Once you have your building permit in hand:

• Foundation: 2-3 weeks
• Framing & rough-ins: 4-6 weeks
• Inspections: Multiple city inspections throughout (foundation, framing, electrical, plumbing, mechanical, insulation, final)
• Interior finishes: 4-6 weeks
• Final inspection & CO: 1-2 weeks

Weather delays, material shortages, and inspection scheduling can all add time. A realistic construction timeline for a standard detached ADU is 4-6 months.

How to Speed Things Up

• Use pre-approved plans: Some ADU designers have plans that have already been through Austin's review process, reducing revision cycles.
• Hire an expediter: Permit expediters know DSD's process and can navigate the system faster. They typically charge $2,000-$5,000.
• Go prefab: Modular ADUs are built in a factory while your permit is being reviewed. Once approved, installation takes days instead of months.
• Submit complete plans: Incomplete submissions are the #1 cause of delays. Make sure your architect includes all required documents on the first submission.

Key Inspections Checklist

Your contractor will schedule these with the city during construction:

1. Foundation (before pouring concrete)
2. Framing (before closing walls)
3. Electrical rough-in
4. Plumbing rough-in
5. Mechanical (HVAC)
6. Insulation
7. Final inspection
8. Certificate of Occupancy (CO)

Each inspection must pass before moving to the next phase. Failed inspections add 1-2 weeks for corrections and re-inspection.