Zoning and Housing Types

Single Family Infill

Seattle’s Single-Family code was written in 1950s at a time when Seattle was more of a town than a city. By most estimates almost two-thirds of Seattle’s land is zoned for single-family. The City has decided to allow growth in these neighborhoods through infill development and accessory dwelling units. As long as there is demand for single-family housing and Seattle has so much land zoned that way, Seattle should allow more home building there.

Δ Idea: Keep Seattle’s single-family neighborhoods a viable option by allowing more new homes in single-family neighborhoods.

  • Small-lot homes – The City Council should make the rules about how new single-family homes get built predictable and easy to understand for both builders and neighborhoods.
  • Cottages – Revise the code to make it easier for the development of cottages in single-family neighborhoods.
  • Accessory Dwelling Units – Currently Seattle’s code allows for Accessory Dwelling Units both inside existing homes (ADUs) and Detached Accessory Dwelling Units (DADUs), but their development has been lacking. The Council should consider options for incentivizing more single-family homeowners to include ADUs in their homes or build a DADU ad allowing both DADU’s and ADU’s in single family zones on the same site in transit served communities. Also, the Council should lessen or even eliminate the criteria for on site parking and raise the height limit to allow a full two stories on DADU’s.
  • Flex housing – All single –family homes should be allowed to be divided into multiple housing units to accommodate new growth. Often as families’ age, and children leave, fewer people occupy larger homes. Allowing larger homes to be divided would accommodate growth and give families new options as they change.
  • Corner lots – There are many corner lots in the city’s single-family neighborhoods that could be subdivided to accommodate an additional single-family home facing a street and alley.
  • Courtyard housing – Clustering attached or detached houses is something that has been tried recently in Portland and would allow more housing in a smaller space. It would also allow an inward facing open space that would allow children the freedom to pay outside in safety with supervision from adults. This type of housing could also fit in multifamily zones.

Read more about these ideas.


Seattle’s multifamily zones range from lower density Low-Rise (LR) zones all the way up to zones that allow high-rise development. These zones are the most efficient in absorbing growth allowing density, height, and aggregation of demand for transit that makes buses, trains, trolleys, and other modes of mass transit for efficient and useful.

Δ Idea: Preserve and expand creative use of density, height, and lot coverage for housing in dense, transit rich neighborhoods

  • Multifamily Tax Exemption (MFTE) Program – The current MFTE program has proven to be a successful tool for providing rental housing affordable to 80% AMI households. The City Council should consider expanding the program to existing housing and extending its geographical boundaries. It should not add more requirements or rules that would discourage developers and landlords from using it to create affordable units.
  • Support continued microhousing development – Microhousing has become an important housing type that meets the demand for housing for many people of many ages, professions, and incomes without subsidy from government. The City Council should do what it can to let microhousing development continue to meet demand for housing from those who don’t drive and want less living space.
  • Keep the LR3 Zone as a growth zone – The Low-Rise 3 or LR3 zone has been a powerhouse of growth, absorbing new people in a wide array of housing types from duplexes and microhousing to repurposed single-family homes turned into small apartment buildings. The City Council should encourage more growth and experimentation in the LR3 zone with different types of multifamily housing and resist the urge to lower heights and density.
  • Focus multifamily growth in areas with high quality transit – Household expenses can be greatly reduced when transit access enables car-free lifestyles. Money saved by not owning a car can be applied to the cost of housing, effectively making it more affordable. The City should craft policies and regulations that promote multifamily development in areas with high-quality transit access—the LINK light rail station areas in particular. To achieve these goals, the Seattle Planning Commission recently made a recommendation to establish Transit Communities.
  • Reduce barriers to housing production – When the real estate market heats up the best thing the City Council can do is let the market produce more housing. More housing to meet demand will stabilize or lower housing prices. When prices flatten, or start to fall, then builders need an incentive to take the risk to build more. And always
    • Create real incentives for developers to build more housing – along with programs like MFTE, the City should find ways to reduce the risks and costs of building additional units in permitted projects. This could include speeding up and streamlining design review for example or developing guarantees for additional rental units.
    • Subsidize housing where people want it and need it most – the data point to the greatest scarcity of housing being at lower levels of income. The City should improve the use of housing
One Response to “Zoning and Housing Types”
Check out what others are saying...
  1. […] suggestion from Smart Growth Seattle concludes that, City Council should not only incentivize more ADU’s and DADU’s for […]

Leave A Comment

You must be logged in to post a comment.