Washington HB 1110 — Middle Housing (Tier 2: cities 25,000-75,000) (WA)
Tracked preemption from the Washington overlay bundle.
Overview
← All state preemptionsWashington overlay roll-upWashington zoning wikiWashington building codesFederal overlaysGlossaryFederal-conflict: Yes
Effective
2024-07-01
Sunset
—
Authority
state
Scope
state:WA
Other Washington preemptions
Washington HB 1110 — Middle Housing (Tier 1: cities >=75,000)Washington HB 1110 — Middle Housing (Tier 3: small cities in Tier 1 UGA)Washington SB 5184 — Lot Splitting for Housing CapacityWashington SB 5290 — Local Permit Review TimelinesWashington HB 1337 — Accessory Dwelling Units StatewideWashington E2SHB 1220 — Comprehensive Plan Housing ObligationsWashington Growth Management Act — Zoning for Growth Targets
Primary-source summary
HB 1110 — Middle Housing (effective July 1, 2024)Trigger predicate
When this evaluates true for a parcel, the law's preempted fields take precedence over base zoning.
AND
city.population≥25000city.population<75000parcel.base_zone_category==res_sf
Preempted fields
6 fields on the base district schema are rewritten when the trigger fires.
| Field | Op | Value | Note |
|---|---|---|---|
base_districts[category=res_sf].max_units_per_lot | floor_at | 2 | Baseline floor: 2 units per lot by-right in all SF residential zones |
base_districts[category=res_sf].max_units_per_lot | floor_at | 4 | 4 units allowed within 1/2 mile of major transit stop if >=1 unit affordable |
base_districts[category=res_sf].min_lot_size_sf | cap_at | base SF lot minimum | |
base_districts[category=res_sf].parking_ratio | cap_at | 1.0 | |
base_districts[category=res_sf].parking_ratio | waive | — | |
review_type | waive_discretionary | — | By-right with objective design standards only |
Citation
Authority source
WA HB 1110 (2023) / RCW 36.70A.635
§ RCW 36.70A.635
Research notes
Tier 2 applies to cities 25,000-75,000. Target intersections with federal AICUZ (JBLM, NAS Whidbey, Fairchild AFB) flagged via federal_conflict_check.