Creating preapproved ADU plans could take 2-3 years, produce few units

With City Council seeking to make it easier to build accessory dwelling units, city staffers provided an update on Feb. 16 about a key part of Council’s ADU strategy: creating a menu of preapproved, publicly available ADU plans.

In a memo, staffers said such a program would take between 20 and 30 months and nearly 2,000 person-hours to roll out. Before plans could be released to the public, staff members would go through a detailed process of gathering community input, soliciting plans from local architects and reviewing the plans. 

The program is part of a recent effort to make ADUs easier and cheaper to build. Council is also exploring whether to allow attached ADUs – think granny flats or garage apartments – and whether to make all ADUs legal in Single Family Residence-Large Lot (SF-1) and Single Family Residence-Standard Lot (SF-2) zones as long as the existing home on the lot is preserved. These proposed rules are part of a broader push to address the city’s rising housing costs.

Council will now decide, based on the report, whether the program is worthwhile. Council Member Kathie Tovo, who has led the charge on ADU policies, worried that staffers’ plan would take too long and provide little in return. “If we were going to implement a program in the manner that staff have described in this memo, I’m not sure it would result in increasing our numbers to an extent that is worth the investment the city would make,” Tovo told the Austin Monitor.

Council has hoped that preapproved plans will make it easier to build ADUs by reducing design costs and expediting permitting. While the preapproved ADU plans may not be entirely free – architects may retain ownership and charge for the plans – they would likely be less costly than hiring an architect. Council also hopes preapproved plans, coupled with other policies, would allow more low- and moderate-income Austinites to build ADUs as a way to generate income, thereby allowing them to stay in their homes as property taxes increase.

How much money preapproved plans could save remains unclear, but it may not be all that much. “A program like this is not going to save the homeowner a tremendous amount of money,” Tovo said. City staffers also noted that preapproved plans have no effect on construction costs. What’s more, securing construction loans is out of reach for many low- and moderate-income homeowners – precisely those who stand to benefit the most from preapproved plans – as staffers explained in a previous memo from last summer. “As I see it, the biggest barrier is still access to capital,” Tovo said. 

Similar programs elsewhere have led to modest increases in housing supply. Staffers noted that in Seattle, for example, only 36 out of the nearly 1,000 ADUs permitted between 2020 and 2021 used plans from the city’s ADUniverse program, which was established in 2019. Seattle builds close to 50 percent more ADUs per year than Austin.

Here in Austin, the impact of preapproved ADU plans could be blunted by additional factors. Zoning regulations like building setbacks, impervious cover requirements, tree regulations, and Austin Energy power line setbacks can either prevent ADUs outright or make them more expensive. Preapproved ADUs would not be exempt from these regulations. Staffers also mentioned that legal obstacles regarding liability ownership of the plans would have to be sorted out. 

If Council ultimately gives the go-ahead, city staffers will first take three to six months to engage with architects and builders as well as low- and moderate-income homeowners “to develop criteria and priorities for ADU designs.” After that, the city will issue a public call for ADU plans. After six more months, the city would review the plans before finally approving them, a process that could take an additional six to 10 months.

Tovo said that the time frame should be shortened for the program to make sense. “I did wonder if, for example, we might partner with a city like Seattle, and see if any of their plans are close enough to the kinds of accessory dwelling units that are being built in the Austin market,” she said. “I think that shaves off literally years.”

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