Middle housing types include: duplexes, triplexes, fourplexes, fiveplexes, sixplexes, townhouses, stacked flats, courtyard apartments, and cottage housing.
Density requirements
- Cities can decide which middle housing types to allow, but must allow at least six of the nine listed types
- Cities with populations over 75,000 must allow at least four units per lot in all lots zoned predominantly for residential uses
- Lots within a ¼ mile walking distance of a major transit stop or if two units are to be affordable housing must allow at least six units per lot.
We have seen estimates that up to 200,000 units are being allowed by HB 1110, alone, above and beyond the yearly average of apartment units (4-6,000) already being built.
According to a CoStar article in June, 2024:
"Multifamily developers added a record number of new apartments across greater Seattle this year.... Roughly 13,000 units were added to greater Seattle’s multifamily inventory in the past 12 months, including a record 4,600 apartments finished in the second quarter, CoStar data shows."
This is also before taking into account the recently passed Seattle Social Housing program or the potential new state "Transit-Oriented Housing" bill (HB 1491),that is moving through the legislature in Olympia now.
Over the 20 years of the projected development, the natural addition of apartment units plus the added units produced by HB 1110 will alone exceed the 112,000 number suggested by the Puget Sound Regional Council and King County, and even the 330,000 target in the Mayor's plan.
We support fulfilling HB 1110 by June 30 and rolling out the Mayor's plan if necessary in a more measured way - taking into account the needs that actually develop and other forces on a local and national level.
We submit that fulfilling HB 1110 by itself will satisfy the projected need for more housing units.
Fulfilling HB 1110 by the State's June 30 deadline, and taking more time to consider the ramifications of the sweeping and impactful One Seattle Plan, is the wiser course.
The increased housing mandated under HB 1110 will by itself multiply the number of units throughout the city, meet the housing targets, and at the same time be more likely to preserve the character of our neighborhoods.