It's About Time We House Everyone

Join AIA's Housing Task Force for an interactive exploration of missing middle housing in Seattle and beyond.

Seattle needs more homes, of all shapes and sizes, for more of our neighbors. AIA Seattle is working to shape policies that rethink the city’s majority single-family zoned areas, which have often restricted access for communities of color, renters, low-income residents, and others these zones were created in the 1950s. We must provide more housing in these zones, connecting people to jobs and transit for a more equitable city. Luckily, there are great options for adding housing that fits into existing single family neighborhoods, providing homes for seniors, immigrants, 20-somethings, teachers, retail workers, those currently unhoused, and many more. These housing types, often called “missing middle,” include duplexes/triplexes/quads (‘plexes), courtyard apartments, cottage clusters.

Missing middle housing integrates a wider range of housing into existing neighborhoods as a modest strategy to meet growing urban housing needs. These types are compatible in scale with single-family homes and provide housing options along a spectrum of affordability to support walkable communities, locally-serving retail, and public transportation options.

Infill housing options currently exist in Seattle’s single-family zones and include accessory dwelling units (ADUs) and detached accessory dwelling units (DADUs). Other options require us to think beyond our current zoning policies, looking forward and backward in time for what else is possible. Seattle communities like Wallingford, the Central District, and Queen Anne historically developed as streetcar neighborhoods with diverse multifamily housing styles built along transit lines. Although the streetcar is now history, relics and modern improvisations on grandfathered-in missing middle housing can be found intermixed within and at the edges of single-family zones. For this program, we’ve added in townhouses/rowhouses and live/work spaces, which typically exist within low-rise (less than 4 story) multifamily residential and mixed-use zones, to help us see where residential density exists today and how it might change in the future.


Seattle Design Festival: Your Mission

Learn more about missing middle housing in Seattle – where we’ve been, where we are, and where we need to go – while making discoveries of your own and helping to build a group-sourced map of housing alternatives that provide more options for everyone in our cities. Join AIA’s Housing Task Force for an interactive exploration of missing middle (or just more dense) housing in Seattle or wherever you live. Check out our examples and add your own finds. Join the conversation as we strive for a more equitable, livable, and sustainable city for all. It’s about time we house everyone!

Things you can do:

  • Check out our reading list on missing middle housing..
  • Help construct our map of missing middle housing locations in your neighborhood or city – see below.
  • Get creative by imagining other “middle housing” possibilities for our neighborhoods. Photograph inspiring existing homes and designs or draw/paint/collage and label what you would like to see and tag @thirdplacedesigncoop on Instagram. Don’t forget to follow us!

Start Mapping!
Help us track down missing middle housing and other alternatives to detached single family homes in your neighborhood or other neighborhoods across your city. This challenge asks you to head outside (please wear a mask!) to capture photos of ADUs/DADUs*, ‘plexes, courtyard apartments, cottage clusters, townhouses/rowhouses and live/work spacesy. Take photos and send us the GPS coordinates (you can use a free GPS app such as GPS Camera 55) or the street address.

Here’s what to look for:

1. ADUs/DADUs*
2. ‘Plexes (duplexes, triplexes, quads, multi-plexes (5+)
3. Courtyard Apartments
4. Cottage Clusters or Bungalow Courts
5. Live-work units
6. Townhouses/Rowhouses
7. Create your own example!

Click on the map below to see examples. Email your photos to Kirsten at We’ll map your find here and give you credit. Prizes for the number of finds, the most difficult to find (cottage housing!), the most creative finds, and more will be awarded.

Find these in your community!  Send your pics and location info to:

DADUs are by definition in someone’s backyard. Please do not trespass to capture your DADU photo. Many DADUs are visible from side angles or via an alley behind the house. When in doubt … find another DADU!