Are ADUs an answer to affordable housing stock?

By: Kathryn McNutt//The Journal Record//January 28, 2022

Accessory dwelling units are a growing trend in the U.S. but building restrictions in Oklahoma cities have kept the numbers down. The ADU behind this residence in downtown Edmond is used as an Airbnb rental. (Courtesy photo/David Chapman)

The construction of accessory dwelling units is on the rise in many U.S. cities as one solution to the shortage of affordable single-family housing stock.

California, Connecticut, New Hampshire and Oregon all permit ADUs statewide, as do many local governments.

The American Planning Association says many cities and counties permit ADUs in one or more single-family zoning districts by right, subject to use-specific standards. Common provisions include an owner-occupancy requirement (for one of the two dwellings), dimensional and design standards to ensure neighborhood compatibility, and off-street parking requirements.

“I love the concept. It’s the No. 1 best way for building affordable housing that we do,” said David Chapman, CEO of Realty1 LLC and associate professor of real estate at the University of Central Oklahoma. ADUs typically are 700 square feet, he said.

“In other places they’re very popular but not in Oklahoma yet,” Chapman said. “Our municipalities aren’t allowing them.”

They offer a relatively inexpensive means to provide more affordable housing options in a neighborhood without changing neighborhood character, according to National Association of Home Builders.

In Oklahoma City, most residential property is zoned R-1, the most restrictive residential use.

“It won’t allow two dwellings on one property,” said Scott Wise, plan review supervisor for the city. “For the most part it’s a density issue.”

A dwelling is defined as having a kitchen, bathroom, living space and sleeping space. Property owners frequently submit ADU plans that meet that definition, Wise said.

If the property is zoned R-1, city staff cannot approve them. “We don’t like being the bad guy, but we are beholden to the code,” he said.

Unless the plans call for renovating a legally existing structure on the property, the only choices are to seek rezoning or ask for a variance, Wise said. A request for a variance costs $1,450, which is nonrefundable.

Rezoning is more likely to be approved if several adjoining properties are being considered together as a planned unit development, he said.

That’s the approach Chapman is taking for a development he wants to build in Edmond. He will seek rezoning for a planned unit development on a city block for construction of 12 two-bedroom houses, each with a one-bedroom ADU.

Chapman has built ADUs on properties in Oklahoma City by converting existing stand-alone garages or other secondary structures, and he built his own in in Edmond’s central business district, which has few restrictions.

“The one behind my house is an Airbnb. Our garage is below it, so it really is a garage apartment,” he said.

ADUs also can be used as an office, art studio, home gym or a residence for an adult child who moves back home.

The city of Tulsa allows ADUs in residential single-family districts by special exception. The city code states they allow efficient use of the city’s existing housing stock and infrastructure, as well as provide a means for residents – particularly seniors, single parents and empty-nesters – to remain in their homes and neighborhoods and obtain extra income, security, companionship and assistance.

A December report from the Urban Institute on the role of single-family housing production in addressing the affordable housing shortage recommends all states permit ADUs on single-family lots as a matter of right.

Only 1.6% of single-family houses have an ADU today, the report said. Increasing that to 3% over the next five years would create an additional 1.17 million affordable homes.

“In the end, the affordability and housing shortage problems are municipal government problems,” said Chapman, a member of the Edmond City Council. “It will rest on the shoulders of municipal planning departments, planning commissions and city councils around the country to develop creative solutions to solve the problems.”