Interest in ADUs rose steadily in the 2010s, and has only grown stronger in the past few years as the metro-wide real estate market became, for many, prohibitively expensive. City planners have seen an uptick in people moving to rezone their property, and in 2019 carved out a place for ADUs in Blueprint Denver — a “planned guidance” document that recommends removing barriers to the units in residential districts. So far, planners say, they’re not aware that any requests have been denied.