They can bring housing density to Denver neighborhoods without the need to scrape away existing homes or drastically change the way those neighborhoods look.
They can serve as a source of income for homeowners struggling to keep up with Denver’s rising cost of living and property taxes. Or they can house aging relatives, providing parents and grandparents with the opportunity to live just a few steps from loved ones but also maintain some privacy.
They have environmental benefits, providing options for the reuse of garages or underutilized space within a home. They create infill housing close to transportation corridors and employment centers instead of driving more sprawl on the periphery of town.
In a city where rent prices have climbed steadily over the last decade and housing supply is estimated to be tens of thousands of units short of demand, accessory dwelling units, sometimes called granny flats or ADUs for short, are broadly viewed as a tool in pushing back against the housing crisis.
The self-contained residential units — sometimes found in cordoned-off basements, sometimes in converted garages, sometimes built from the ground up, but always an accessory to the main home on a property — have existed in various forms for generations. But they are gaining popularity in markets from the Midwest to the Pacific coast as broad swaths of the country deal with a lack of available, attainable housing.
There’s one big problem with the tiny style of housing in Denver, advocates say: too few of them are being created.
Between Denver’s big zoning code overhaul in 2010 and the end of 2021, the city issued construction permits for 393 ADUs. That’s roughly 33 permits per year over that span. The high-water mark was 2019 when 71 permits were pulled. In 2021, the city issued 64.
Rezoning hearings for residents seeking to build ADUs on the Denver properties are common if not abundant. Monday night’s City Council agenda included three public hearings seeking approval for new ADUs.
“Everybody understands the potential and doesn’t understand why they’re not being built,” said Renee Martinez-Stone, a former Denver Planning Board member and Denver Housing Authority staffer who is leading a program focused on fostering more ADU development in west Denver neighborhoods.
“There’s a pretty complex regulator environment for ADUs,” said Martinez-Stone, who recently authored a report detailing the challenges homeowners in west Denver face. “That’s one of the biggest obstacles in Denver. Small development is disproportionately impacted by fees and requirements.”