ADU Permit Requirements in Justin, TX
City of Justin is an incorporated municipality in southern Denton County, TX, on the northwest edge of the DFW metroplex along the TX-156 / I-35W corridor near Roanoke and Northlake. The Building Inspections & Permits division sits inside the Development Services Department (which also includes Planning & Zoning, GIS, and Code Compliance). All building permit applications, plan submittals, inspection requests, and contractor registrations are processed through the iWorQ online portal (in production since January 2, 2023). All contractors must register with the City of Justin before performing work within city limits. Adopted codes (verified on the live building dept page): 2018 International Building Code, 2018 International Residential Code, 2018 International Energy Code, 2018 International Plumbing Code, and 2017 National Electrical Code (Justin is on the 2018 I-codes, not the 2021 cycle some neighboring DFW cities use). Staff contacts published on the page: Sasha Torres (Building Official) and Patricia Hollis (Permit Technician); direct email addresses are routed through CivicPlus contact forms rather than public mailto links, so no direct email is listed. Fee schedule is published as the Treeline Fees How-to Guide PDF served from the city's DocumentCenter. Counter hours are not posted on the building dept page or the homepage; main city phone line 940-648-2541. ZIP 76247 also covers neighboring portions of Roanoke and unincorporated Denton County; for parcels inside Justin city limits, this department is the AHJ. Practical notes for homeowners: vicinity to DFW International Airport and Alliance/Fort Worth Meacham airspace means FAA Part 77 notice may be triggered for tall accessory structures (towers, large flagpoles, antennas) depending on parcel location; the area is in TDLR / Texas-administered seismic and wind territory with ASCE 7 wind design for North Texas (DFW tornado-alley periphery) and expansive (shrink-swell) North Texas clay soils that drive foundation and pier design for residential additions, pools, and retaining walls. TxDOT FM-156 / SH-114 corridor parcels may require a TxDOT driveway/right-of-way permit in addition to the city permit.
By Joey, Founder · Last verified May 23, 2026 · How we research →
When you need a ADU permit in Justin
Detached accessory dwelling units require all trade permits with full architectural plans. Zoning approval from the City of Justin is required, and ADUs are not permitted in all residential districts. Contact Justin Development Services at (940) 648-2541 before planning.
Attached or interior accessory dwelling units require building, electrical, and plumbing permits. Verify zoning compliance and rental restrictions with Justin Development Services at (940) 648-2541 before starting.
ADU Permit Costs: Justin vs. Nearby
| City | Estimated Fee |
|---|---|
| Justin | N/A |
| Houston | $500 – $5,000 |
| San Antonio | $500 – $5,000 |
| Dallas | $500 – $5,000 |
Fees shown are estimates based on local building code data. Actual fees may vary based on project scope and valuation. See all Justin permit costs →
Zoning Considerations
ADU regulations vary dramatically by state and city. Many states (CA, OR, WA) have preemption laws that override local zoning restrictions. Check both state law and local zoning before designing.
Estimated Project Timeline in Justin
Here's a typical timeline for a adu project in Justin, TX:
Timeline is based on Justin's typical about 4 weeks permit processing time. Actual timelines vary by project complexity, completeness of application, and current department workload.
Need an ADU permit in Justin, TX?
Answer a few quick questions for a personalized answer about your specific project.
Check Now, Free →Building Department Contact
Frequently Asked Questions
Contact Justin's building department for current ADU permit fee information. Fees typically vary based on project scope and valuation.
It depends on the specifics of your project. Some smaller ADU projects may be exempt from permit requirements, while larger ones typically require a permit. Use our free lookup tool to check your specific situation.
Working without a required permit in Justin can result in fines, stop-work orders, being required to remove completed work, and complications when selling your home. It's always best to check first.
Typical approval time for ADU permits in Justin is about 4 weeks. More complex projects may take longer if plan review is required.
Learn More About ADU Permits
Read our complete guide covering permit requirements, costs, common exemptions, and the application process.
Read ADU Guide →