Accessory Dwelling Units (ADUs) are an emerging category of residential construction. What we used to call an 'in-law' built inside or next to an existing home has promise to solve several problems of today's city.
ADU regulations allow existing homeowners to build on their existing property, by making it easier for those homeowners to get permits which can expand a single-family dwelling by adding one or more small dwelling units. The framework keeps the size of these units small, which tends to keep construction costs low.
The way that units like this have tended to be built is for 'flippers', or small residential developers, to buy homes from homeowners, invest in permits and buildout of these structures, and resell or rent the now-more-valuable property.
When working properly, ADUs can allow homeowners to unlock the value of the land their homes sit on, and let them stay in our city.
Increased Housing Stock
Our cities need a significant increase in the number of residential units - homes, apartments, cottages, and others - to meet the demand of our growing population. Housing development has lagged population growth for years, and it will take some time to catch up.
Large-scale apartment/condo/townhouse developments are one part of the solution, but augmenting these strategies with thousands or tens of thousands of homeowners who can build individual units means an uptick in the number of project drivers - we are less dependent on large, risky, high cost, long-term development ventures to build our housing stock. Distributed risk and distributed benefit result from ADUs at significant scale.
Increased Density in Low-Rise Neighborhoods
Many residential neighborhoods in our city prefer buildings and homes to stay low to the ground - five story and taller buildings might be welcome (or at least accepted) in high-traffic commercial corridors, but on our residential streets, we're still a one- and two-story city. ADUs increase infill construction, bringing higher neighborhood density, which helps with all sorts of other problems. Busier streets are safer streets. Denser neighborhoods can support retail services, keeping dollars circulating within them. Transit functions better when riders use it. Tax revenues increase. Schools are busier and better funded.