Accessory Dwelling Units (ADUs)
Enabling building on residential lots
Building more units on existing plots
In Austin, Texas, rents climbed faster than almost anywhere in the country over the past decade.
Austin amended city code in 2015 to cut the minimum lot size for building an ADU from 7,000 to 5,750 square feet, eliminated the requirement for a second driveway, and reduced required parking to one space—lowering parking rules that often make backyard homes too expensive to build
In 2023 and 2024, Mayor Kirk Watson and Austin City Council legalized up to three homes on most single-family lots, including backyard and small detached units, and further shrank minimum parcels from 5,750 to 1,800 square feet. City hall communicated these changes to residents via a dedicated Home Options for Mobility and Equity (HOME) webpage with a phase-by-phase timeline, downloadable guides, a live applications dashboard, a webinar series, and appointments set aside for HOME questions.
The Impact:
- Approximately 120,000 homes have gone up since 2015, and the city has become one of the only major markets where rents have fallen since the pandemic—down 19% from 2021 to 2025
- 2,850 ADU permits issued from 2015-2024, increasing to 260 per year from an average of 37 per year in the decade before
- New construction built under HOME cost hundreds of thousands of dollars less than traditional single-family homes
What you can do with this idea:
- Add additional housing supply to low-density residential zones
- Provide more housing variety, and specifically missing middle housing, that also offers more affordability to city residents
- Give homeowners more flexibility in land use and wealth-building
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