There is broad support to allow backyard cottages, duplexes and triplexes in residential neighborhoods, according to a new Zillow survey covering 26 U.S. metropolitan areas struggling with housing affordability. The new research found that 77% of all homeowners and renters surveyed voiced support for construction of either new accessory dwelling units (ADUs), duplexes, or triplexes in residential neighborhoods.

A clear majority of homeowners surveyed, 73%, voiced support for at least one modest densification option, including either the construction of new backyard cottages or the building of new duplexes or triplexes. Support among renters was even higher, with 84% of renters supporting at least one modest densification measure in neighborhoods to help increase housing supply. Research has shown that modest densification through the addition of accessory dwelling units (ADUs), duplexes and triplexes could yield millions of new homes nationally, helping slow runaway price growth and improving access to public transit.

"We are facing a housing crisis that's touched most communities across the country, pushing housing affordability to the center of the conversation for many," said Manny Garcia, a population scientist at Zillow. "One of the most effective ways out of this crisis is to build more homes. Modest densification measures, like adding a small apartment in a backyard or converting existing homes into duplexes, could create millions of new homes."

Zillow's survey asked homeowners and renters how to best address affordability issues during a red-hot real estate market defined by limited housing inventory, rising interest rates, a steady increase in home prices and climbing rents across the country. These factors are compounded by a lost decade of new home construction that caused a shortfall of 1.35 million new homes in 35 metro areas alone. This latest survey, along with previous research, shows a growing consensus among homeowners and renters that more housing should be created in their own neighborhoods to address affordability.

"This survey shows that residents of more than 20 major U.S. metros — including homeowners — understand that building more homes in our neighborhoods is a credible and viable policy tool to increase housing supply and address affordability, while leaving a positive impact on their community in the long term," said Garcia.